www.mnf-journal.com Page 1 Molecular Nutrition & Food Research Pharmacological and nutritional effects of natural coumarins and their structure-activity relationships Jing-Jing Zhu, Jian-Guo Jiang* College of Food and Bioengineering, South China University of Technology, Guangzhou, 510640, China *Author for correspondence (e-mail: email@example.com; phone +86-20-87113849; fax: +86-20-87113843) Abstract Coumarins are fused benzene and pyrone ring systems with a wide spectrum of bioactivities including anti-tumor, anti-inflammation, antiviral and antibacterial effects. In this paper, the current development of coumarins-based drugs is introduced, and their structure-activity relationship is discussed by reviewing the relevant literatures published in the past twenty years. Coumarin molecules can be customized by the target site to prevent systemic side effects by virtue of structural modification. The ortho-phenolic hydroxyl on the benzene ring had remarkable antioxidant and anti-tumor activities. Coumarins with aryl groups at the C-4 position have good activities in anti-HIV, anti-tumor, anti-inflammation and analgesia. C-3 phenylcoumarins have strong anti-HIV and antioxidant effects. Tetracycline pyranocoumarins can significantly inhibit the HIV, osthol structural analogues have antimicrobial activity. Praeruptorin C and its derivatives play an important role in lowering blood pressure and dilating coronary arteries, and khellactone derivatives have significant Received: 24-Dec-2017; Revised: 27-Apr-2018; Accepted: 27-Apr-2018 This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/mnfr.201701073. This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 2 Molecular Nutrition & Food Research inhibitory effects on AIDS, cancer and cardiovascular diseases. It is concluded that the specific site on the core structure of coumarin exhibits one or more activities due to the electronic or steric effects of the substituents. This review is designed to be conducive to rational design and development of more active and less toxic agents with a coumarin scaffold. Key words: Coumarins / Bioactivity / Structure / Pharmacology / Effect Abbreviations: ADR, adriamycin; ALT, alanine aminotransferase; AST, aspartic transaminase; AKP, alkaline phosphatase; BHT, butylated hydroxytoluene; CDK, cyclin-dependent kinase; CKI, cyclin-dependent kinase inhibitor; COX-2, cyclooxygenase-2; Con-A, concanavalin A; DHMC, 4-methyl-7,8-dihydroxycoumarin; DR5, death receptor 5; EC50, half maximal effective concentration; ERK, extracellular regulated protein kinase; GSH, glutathione; GST, glutathione transferase; GPX, glutathione peroxidase; Hsp90, heat shock protein 90; IN, integrase; IC50, half maximal inhibitory concentration; IL-6, interleukin-6; IFN-γ, interferon γ; JNK, Jun N-terminal kinase; 5-LOX, 5-lipoxygenase; MAPK, mitogen activated protein kinase; MBC, minimal bactericidal concentration; MDR, multidrug; MDA, methane dicarboxylic aldehyde; MIC, minimum inhibitory concentration; NSCLC, non-small cell lung carcinoma cell; NO, nitric oxide; NOS, nitric oxide synthase; ο-DHC, the coumarins of the ortho-diphenol hydroxyl group; RT, reverse transcriptase; PR, protease; PGE2, prostaglandin E2; PGD2, prostaglandin D2; QSAR, quantitative structure–activity relationship; ROS, reactive oxygen species; SOD, superoxide dismutase; TERT, human telomerase reverse transcriptase; TI, therapeutic index; TNF-α, tumor necrosis factor-α; VCR, vincristine; Vpr, viral protein R. 1 Introduction 2 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 3 Molecular Nutrition & Food Research The coumarin class of organic compounds consists of a 1, 2-benzopyrone ring system as a basic parent scaffold. It is a general designation of a large class of phenolic substances found in plants and made of a fused benzene and α-pyrone ring. Coumarins, initially found in tonka bean (Dipteryx odorata Wild),[3, 4] are distributed over nearly 30 families and 150 species. A few important ones are Rutaceae, Umbelliferae, Clusiaceae, Caprifoliaceae, Oleaceae, and Apiaceae. Some plants like Fructus cnidii, Fructus psoraleae, Angelicae pubescentis, Radix Angelicae dahuricae, Radix Peucedani, Cortex fraxini are rich in coumarins. Coumarins are subdivided into simple coumarins, furanocoumarins, pyranocoumarins and other coumarins based on the differences of substituent locations and characteristics in the chemical structures. Coumarins are characterized by low molecular weight, easy synthesis and high bioavailability, as well as a variety of pharmacological activities. Recently, they have become important lead compounds in drug research development. The toxicity of coumarins and their derivatives is low, and their target organ toxicity is species-specific and non-genotoxic, which is associated with the metabolism and detoxification abilities of different species. Coumarins exhibit a wide range of pharmacological activities including anti-HIV, anti-tumor, antihypertensive, antihyperlipidemic, anti-inflammatory analgesic etc. The relationships between their pharmacological effects and chemical structures are the basis of drug design. Therefore, it has become a priority for drug research and development to study more plant coumarin ingredients, find effective lead compounds, improve the extraction processes, synthesize and screen highly efficient coumarins with low toxicities. This review focuses on the pharmacological properties and structure-function relationships of various coumarins, many of which are derived from plants known or thought to have medicinal properties, in order to find more targeted and efficient coumarin lead compounds and provide ideas for structural transformation and optimization. 2 Structure and classification 3 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 4 Molecular Nutrition & Food Research 2.1 Simple coumarins 1, 2-benzopyrone is the basic parent nucleus of coumarins (Fig. 1). Generally speaking, the ones where only the benzene ring is replaced by other groups such as hydroxyl, methoxyl, methylenedioxy and isopentenyl, without forming furan rings or pyran rings between C-7 hydroxyl groups and C-6 or C-8 positions, are called simple coumarins. For example, the esculetin from Cortex Fraxini and the aurapten from Narirutin belong to simple coumarins. The isopentenyl groups can also be directly connected to the C-5, C-6 or C-8 positions in addition to the oxygen atom in benzene ring. However, the C-6 or C-8 positions at the benzene ring are easier to be alkylated because of the higher electronegativity from the aspect of biosynthetic pathway. Thus, the C-6 or C-8 positions are more often to be substituted by isobutenyl. 2.2 Furanocoumarins Furanocoumarins are formed by the substitution of furyl at the 6,7 or 7,8 position of the simple coumarin. As the formation of furan ring is between 7-hydroxyl and 6-isopentenyl, the body of the furan ring, benzene ring and α-pyrone ring is in a straight line, which is known as linear furanocoumarin (Fig. 2). The imperatorin in Radix Angelicae dahuricae and psoralen in Fructus psoraleae belong to linear furanocoumarins. When the furan ring is generated at the 7-hydroxyl and 8-isopentenyl, the structure of the furan ring, benzene ring and α-pyrone ring is in a polyline, which is called as angular furanocoumarin (Fig. 3). The isobergapten from Heracleum hemsleyanum Diels is classified as angular furanocoumarin. Furanocoumarins are abundantly present in Umbelliferae, many of which are the main ingredients of some plants such as Radix Angelicae dahuricae, Radix Peucedanim, Angelica sinensis. 2.3 Pyranocoumarins 4 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 5 Molecular Nutrition & Food Research Pyranocoumarins refer to a series of compounds in which the 7-hydroxyl is condensed with an isopentenyl substituted at the C-6 or C-8 positions of the coumarin parent nucleus. When the 7-hydroxyl and 6-isopentenyl form a pyran ring, the pyran ring, the benzene ring and the α-pyrone ring are in a straight line, thus forming a linear pyranocoumarin such as xanthoxyletin. As the formation of the pyran ring is between 7-hydroxyl and 8-isopentenyl, the main body of the pyran ring, benzene ring and α-pyrone ring is in a polyline, which is known as angular pyranocoumarin (Fig. 4), such as praeruptorin C and pteryxin. According to the summary of this paper, the tetracyclic pyrancoumarins (Fig. 5) and the khellactone derivatives (Fig. 6) have a variety of biological activity, and are considered to be the lead compounds of studying the structure-activity relationships. 2.4 Bicoumarins, isocoumarins and other coumarins Dicoumarins are the dimer or trimer of coumarins (Fig. 7). Isocoumarins, the isomer of coumarins, are often the derivatives of dihydro coumarins in plants. Other coumarins are often substituted by phenyl, hydroxyl and isopentenyl at C-3 or C-4 positions in the α-pyrone ring (Fig. 1). 3 Pharmacological effects and structure-activity relationships 3.1 Anti-human immunodeficiency virus (HIV) activity Acquired Immune Deficiency Syndrome (AIDS), caused by HIV-1 (human immunodeficiency virus), is a degenerative disease of the immune system and central nervous system. Food and Drug Administration (FDA)-approved anti-HIV drugs include nucleoside reverse transcriptase inhibitors (NRTIs/ NtRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), fusion inhibitors (FIs), co-receptor inhibitors (CRIs), integrase inhibitors.[15, 16] In 1987, zidovudine, the first nucleoside drug of blocking the HIV reverse transcription (RT), was born. Subsequently, new drugs such as didanoside and zalcitabine continued to emerge. Although these drugs contributed to a significant inhibitory effect on HIV, they had widespread 5 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 6 Molecular Nutrition & Food Research serious drawbacks such as poor selectivity and HIV susceptibility. In 1992, Kashman et al.  first discovered that the extract of Calophyllum lanigerum had a strong inhibitory effect on the replication of HIV along with the protective effect on human normal cells. The active substances were the coumarin monomers--Calanolide A (1) and Calanolide B (2) (Fig. 5), both of which belonged to the tetracyclic pyrancoumarins. They were not only highly specific to HIV-1 RT with a low dose, but also contributed to a strong inhibitory effect on commonly used anti-HIV drug resistant strains. The drug is the first anti-HIV botanical extract that enters into clinical trials, followed by the gradual appearance of a large number of structurally modified derivatives with increased activity. Afterwards, many structurally different coumarins used as new anti-HIV drugs are found to display potent anti-HIV activity, most of which are identified from natural sources, especially green plants. The studies of natural active ingredients of coumarins and their anti-HIV effects and mechanisms in recent years are shown in Table 1. Coumarin plays a major role in inhibiting HIV replication, of which the main target is HIV RT, HIV protease (PR) and HIV integrase (IN). Preliminary studies have shown that some coumarin derivatives work in combination with the active sites of the enzymes to decrease the HIV activity, the IC50 of which is 0.5~2.5 μg/mL. Apart from tetracyclic pyranocoumarins, many other structures such as khellactone derivatives and some active groups--C-5 epoxy group, C-3 phenyl group and C-4 phenyl group, attribute great significance to the specific effect on the HIV. Gu et al. extracted five kinds of coumarins from the Angelica apaensis, which were oxypeucedanin (3), oxypeucedanin hydrate (4), isoimperatorin (5), byakangelicol (6), byakangelicin (7) (Fig. 2). Oxypeucedanin (3), oxypeucedanin hydrate (4), isoimperatorin (5) are different in C-5 substituents, resulting in differences in the anti-HIV activity. The results showed that the activity of oxypeucedanin (3) exceeded that of oxypeucedanin hydrate (4) and the isoimperatorin (5) (Table. 1). The C-5 position of the oxypeucedanin (3) (TI=17.59) is an epoxy group, while the oxypeucedanin hydrate (4) (TI=3.61) and the isoimperatorin (5) (TI=4.54) are 6 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 7 Molecular Nutrition & Food Research respectively the substituents of the opened epoxy ring and the phenyl group in C-5 position, suggesting that the epoxy substituent in C-5 position plays an essential part of the effect on HIV. The HIV-1 viral protein R (Vpr) is an accessory protein that has multiple roles in the pathogenesis of HIV-1. 3-phenylcoumarins have been identified to inhibit Vpr-dependent viral infection of human macrophages and the cell cycle arrest activity of Vpr in yeast, of which the minimal pharmacophore and more potent derivatives through a structure-activity relationships study also have been synthesised. The hydrophobic region about residues Glu-25 and Gln-65 in Vpr mutants might be potentially involved in the binding of the inhibitor of 3-phenylcoumarins. The small molecule inhibitors like 3-phenylcoumarins may be the novel bioprobes to expose the targeting site on Vpr, thus providing a convenient approach to explore more targeting sites on the protein. A series of coumarin derivatives as HIV-1 IN inhibitors are measured by quantitative structure–activity relationship (QSAR) analysis. Srivastav et al. built the regression models of two different variable selection approaches.  The HIV-1 IN inhibition activity is predicted by the genetic function approximation and sequential multiple linear regression. The study displayed that two coumarin units linked via an aryl junction were the most important for HIV-1 IN inhibitory activity. Removing any one coumarin unit would result in the lowering of activity. As the two of the original four coumarin units were removed from compound 8 (Fig. 8), the potency was reduced (compound 9). In addition, if one more coumarin unit together with the joint was removed from the compound 9, the effectiveness was significantly decreased. The effect was enhanced by replacing the central phenyl ring with a more extended aromatic with higher lipophilicity. Presence of nitrogen in compound 10, 11 and 12 reduced the aromaticity and the value of LogP, thus showed low biological activity. The inhibitory effects and the structure-activity relationships of seven coumarins were studied on the replication of HIV-1 RT, HIV-1 PR and HIV-1 IN. 11-desmethyl-inophyllum B (13) together with its precursor compound----12-carbonyl-11-demethyl-inophyllum B (14) (Fig. 5), tricyclic 7 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 8 Molecular Nutrition & Food Research linear intermediate and tricyclic angular intermediates all showed inhibitory effects on HIV-1 PR. The other three compounds were tricyclic linear intermediates for the synthesis of calanolide A (1) and 11-desmethyl analogues. There was little inhibitory activity against HIV-1 PR for these three compounds. In the chemical structure, the largest difference between the two groups is the C-4 position substituents, which are phenyl, n-propyl, aromatic and saturated alkanes. It is therefore speculated that the 4-position substituted phenyl contributes to the inhibition of HIV-1 PR. Similar results were obtained by other studies, in the structural analogs of calanolide A (1), the functional groups at C-10, C-11 and C-12 positions and their stereochemical structures played a key role in the activity of these compounds, while the C-4 position also had a significant effect on the biological activity of these compounds. ,  Tetracyclic pyranocoumarins can be considered a necessary structural skeleton for HIV-1 inhibitory activity. Calanolide A (1), inophyllum B (15) and cordatolide A (16) (Fig. 5) all had inhibitory activities on HIV-1 RT in vitro. Calanolide A (1) had the strongest activity among them with an IC50 of about 0.07 μg/mL. Calanolide A (1) showed strong inhibition and high selectivity on RT of recombinant HIV-1 recombinant virus, but in the range of test concentration, there was no inhibitory activity against cellular DNA polymerase and HIV-2 RT.  Khellactone derivatives (17) (Fig. 6) (C-3 cis-structure, C-4 cis-structure) is a 7,8-pyranocoumarin, whose structure is characterized by two chiral carbon atoms of 3',4' positions connected with different acyloxy groups in the pyran ring. Suksdorfin (18) has a significant inhibitory effect on HIV replication (EC50=1.3μM, TI>40). Huang et al. tested and compared the activities of 10-Di-O-(-)-camphanoyl-(+)-cis-khellactone (DCK) (19) and its cis-trans isomers of three different configurations, and results showed that the anti-HIV activity of DCK (19) was stereoselective and its EC50 was more than a thousand times higher than that of other three isomers.  The data of other types of esters also indicate that the cis-ester activity is higher than the corresponding trans-ester. In the cis structure, the activity of (+)-cis structure is higher than the (-)-cis 8 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 9 Molecular Nutrition & Food Research structure. Therefore, (+)-cis is considered an important structural factor for the anti-HIV activity of coumarins. The khellactone mother nucleus structure (17) was used to be linked by different substituents for the anti-HIV activity screening of the synthetic coumarin derivatives. [31, 32] It was found that the C-3 methyl, C-4 methyl and C-5 methyl substituted compounds had higher activities, while C-6 methyl substitution and alkoxy substituted compounds had lower activities, and other alkyl-substituted compounds maintained certain anti-HIV activity. When the aromatic group and the electron absorption group were replaced, the khellactone derivatives almost had no anti-HIV activities.[31, 32] 3.2 Anti-tumor activity In recent years, increasing natural coumarins with anticancer activity are isolated and identified from plants. At present, the anti-tumor drugs targeting heat shock protein 90 (Hsp90) can not only overcome the narrow tumor-inhibitory spectrum of the single target drug, but also identify and distinguish normal cells from tumor cells. Studies have shown that coumarin antibiotics may become another class of antineoplastic agents with Hsp90 inhibiting effect.  4-methyl-7, 8-dihydroxycoumarin (DHMC) (20) (Fig. 1) cause apoptosis of non-small cell lung carcinoma cells (NSCLC), where the mechanism of action was its partial inhibition of the signaling pathways independent of reactive oxygen species  of the extracellular regulated protein kinases/mitogen activated protein kinases(ERK/MAPK). DHMC (20) inhibited the growth of mononuclear leukemia cells (U-937) and myeloid leukemia cells (HL-60), and a preliminary study indicated that phenolic hydroxyl was the active group of the DHMC-induced apoptosis. In order to further investigate the structure-activity relationships of the coumarins with the ortho-diphenol hydroxyl group (ο-DHC), a series of DHMC (20) derivatives and their lactone ring-opening analogues and δ-lactone analogues were synthesized to test their activities of differentiation and apoptosis of induced U-937 cells. It turned out that the δ-lactone was necessary for the activity of ο-DHC, and 9 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 10 Molecular Nutrition & Food Research more importantly, the integrity of coumarin parent nucleus contributed to the biological activity of ο-DHC. Furthermore, DHMC (20) could reduce the production of ROS caused by doxorubicin in human breast cancer cell (MCF-7) without reducing the anti-tumor effect. It was demonstrated that 5,7-dihydroxy-4-methyl-6-(3-methylbutanoyl)-coumarin (DMAC) (21) (Fig. 1) exhibited proapoptotic activity in human colon cancer cells.  Jun N-terminal kinase (JNK) activation was involved in the DMAC-mediated apoptosis initiation, which was independent of the ROS generation. Furthermore, DMAC could improve the therapeutic effect as combined with conventional anticancer drugs like 5-FU. A structure–activity relationship study showed that DMAC-1 with a phenyl substitution at C-4 position, but not DMAC-3 with no alkyl substitution at C-6 position, exhibited cytotoxicity, which is similar to the results for Ochrocarpin B (22) (Fig. 3), which exhibits an alkyl group at C-6 position and a phenyl group at C-4 position. It is indicated that the alkylation at C-6 position and the phenyl group substitution at C-4 position are necessary for apoptosis-inducing activity and enhancing bioactivity. This can be used to develop a novel structure-based drug design for a coumarin-associated anticancer approach. Gacche et al. designed and synthesized a series of hydroxyl-substituted simple coumarins to evaluate their antioxidant activities and anti-tumor activities. 4-methyl-6-hydroxycoumarin, 5-methyl-7-hydroxycoumarin and 6, 7-dimethyl-4-hydroxycoumarin were attributed outstanding effects on HeLa-B75, HL-60, HEP-3B. The hydroxyl groups at C-4, C-6 and C-7 positions could significantly enhance the inhibitory activities on tumor cells. The quantum chemical parameters of these compounds showed that the stronger the molecular rigidity was, the worse their activities were, with no obvious dose-effect relationships. Among the series of synthetic coumarin derivatives with 4-hydroxyl groups, 5, 7-dimethoxy-4-hydroxycoumarin showed significant inhibitory activity on several tumor cells such as MCF-7, HL-60, U937 and Neuro2a, further confirming that the presence of C-4 hydroxyl groups enhanced the anti-tumor activities of coumarins. 10 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 11 Molecular Nutrition & Food Research Two kinds of coumarins: osthole (23) and murraol (24) (Fig. 1) were extracted from Phellolophium madagascariense Baker which is a Madagascar folk medicinal umbelliferous plant. The proliferation of human hormone-sensitive prostate cancer cell line LNCaP, human prostate cancer hormone-resistant cell lines PC3 and DU145, murine leukemia cell line L1210 were inhibited by both of the two coumarins, whose aromatic rings all contained the isopentenyl groups. Furthermore, the antitumor activity against human pancreatic adenocarcinoma cell line PANC-1 of isoprenylated coumarins also has been evaluated under nutrient-rich and nutrient-deprived conditions. It was found that the length of the isoprene tail and the precise substitution position in the coumarin scaffold have a significant effect on the efficacy of the isoprenylated coumarins. The ether coumarin farnesylated at C-6 position (compound 25, n=3, Fig.9) was confirmed to have the highest cytotoxic activity with an LC50 value of 4μM, which could induce morphological changes of apoptosis in PANC-1 cells after a 24h incubation. The structure-activity relationships demonstrated that the substitution at the C-6 position and the presence of a farnesyl isoprenyl tail are important structural features for enhanced cytotoxicity. The high demand for these isoprenylated compounds for the treatment of pancreatic cancer and selective cytotoxicity on nutrient-deprived cancer cells attach significant importance to the development of lead compounds to target pancreatic cancer.  Praeruptorin A (26) (Fig. 6) isolated from Peucedanum praeruptorum shows a reversal of P-glycoprotein-mediated multidrug (MDR) activity. The expression of P-glycoprotein was down-regulated at protein and mRNA levels, indicating that khellactone (17) coumarins are a class of potential MDR reversal agents. A series of compounds of the genus Praeruptorin A (26) analogues were obtained by further structural modification, of which compound 27 showed a stronger reversal activity of P-glycoprotein-mediated MDR resistance than that of Praeruptorin A (26) and verapamil. Compounds 28 obtained by the methoxylation of compound 27 cinnamoyl groups could enhance its reversal of P-glycoprotein-mediated MDR activity.[46, 47] 11 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 12 Molecular Nutrition & Food Research Lv et al. have reported the synthesis of 15 kinds of 2-phenylpyrimidine coumarin derivatives and their antitumor activities (29-32) against CNE2, Cal27, and KB cell lines. The study of structure-activity relationships (Fig.10) indicated that compounds 29, 30, 31 and 32 possessed high activities against the CNE2 cell lines; compounds 30, 31, and 32 exhibited potent activities against the Cal27 cell lines; and compounds 29, 30, and 32 showed high activities against the KB cell lines, which are comparable with doxorubicin. These compounds have strong effects on inhibiting tumor cell proliferation in an in vitro antitumor study. Compound 32 displayed strong inhibitory activity against CNE2 cells and the most potent inhibition activity on telomerase with an IC50 value of 0.82 ± 0.14μM. Cell proliferation was also blocked by compound 32, accompanied by shortened telomere length. In a molecular docking assay, compound 32 was combined with the catalytic subunit of telomerase human telomerase reverse transcriptase (TERT) via multiple modes and replaced the nucleotide with an active substrate. It is highly likely that 2-phenylpyrimidine coumarins and their derivatives have the potential to become pilot compounds in antitumor drugs. The anti-tumor activity of natural coumarins is closely related to their chemical structure, which is influenced by the differences in the structures of the coumarins parent nucleus, the number and location of hydroxyl substitutions, the mode and extent of hydroxylation. The antitumor activity of the coumarin functional group can be summarized as o-DHC, alkyl group at C-6 position & phenyl group at C-4 position, C-4 hydroxyl group, aromatic ring containing the isopentenyl group, khellactone coumarins, the presence of a farnesyl isoprenyl tail, and 2-phenylpyrimidine coumarin derivatives etc. The actions of these coumarin active groups on tumor cells including the molecular mechanisms have been studied in detail through a variety of cell models, and results showed that they mainly acted on cell cycles and multiple signaling pathways, or induced apoptosis to inhibit tumor cell proliferation. Specifically, coumarins can inhibit tumor angiogenesis and serine proteases, down-regulate NF-kB, induce caspase-dependent apoptosis through mitochondrial pathway, inhibit the activity of NAD(P)H benzoquinone oxidoreductase and the expression of HER2 and EGFR, 12 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 13 Molecular Nutrition & Food Research and hence prevent tumorigenesis. Specific natural ingredients of coumarins with anti-tumor activity are summarized in Table 2. 3.3 Antioxidant activity Excessive free radicals in the human body can interact with numerous substances such as fatty acids, proteins, DNA to capture their hydrogen atoms, causing damage to the relevant cell structure and function, thereby leading to a variety of diseases. Hydroxyl substituents on the basic skeleton of coumarins are active radicals scavenging free radicals. Substitution positions and forms of hydroxyl groups have a significant effect on the antioxidant activity. It is found that the hydroxyl on the benzene ring is the main active sites of scavenging free radicals of antioxidant activity. The number of hydroxyl groups on the benzene ring plays a significant role in scavenging free radicals, especially the coumarins with the hydroxyl structure of ortho-diphenol possessing a superior antioxidant activity. The intramolecular hydrogen bonds formed between ortho-diphenol hydroxyl and free radicals are more stable. Esculetin (33) (Fig. 1) was isolated from the semen Euphorbiae lathyridis, and DPPH radical scavenging experiments and anti-oxidation experiments using lard were carried out to measure its antioxidant activity. The results indicated that the final concentration of scavenging DPPH free radicals (IC50 =0.058μg/mL) was much lower than that of VC (IC50=0.542μg/mL). Moreover, it was found that the antioxidant activity of coumarins was related to the number and location of the phenolic hydroxyl group, especially the ο-DHC. The reason for this is that the phenol hydroxyl group possesses ortho-orientable electron donor groups to form a stable free radical after the hydrogen supply. A density-functional theory was applied to describe the relationships between the antioxidant activities and the coumarins structures, i.e. that the ο-DHC scavenged free radicals was dominated by the direct transfer of H atoms, and the O-H dissociation enthalpy involved in this process could be 13 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 14 Molecular Nutrition & Food Research used as an indicator of free radicals scavenging activity. For the non-ortho-bisphenol-based coumarins, their structures had little effect on the decrease of O-H dissociation enthalpy, therefore the antioxidant abilities were weaker than that of ο-DHC. The B ring (1, 2-pyrone) of the coumarin parent nucleus had little effect on the antioxidant activities of coumarins because of its weak electron withdrawing group. Using a TLC DPPH assay, Vessela et al. analyzed the capacity of 4-hydroxy-bis-coumarins to scavenge DPPH radicals and their activity of shortening the length of lipid oxidation chains. It turned out that only compounds 34 and 35 (Fig. 7) increased the oxidation stability of the lipid sample and their efficiency and reactivity as chain-breaking antioxidants. All the other compounds 36, 37 and 38 (Fig. 7) had no ability as antioxidants. Compounds 36 and 37 have no free phenolic groups in their molecules, causing them to be inactive as antioxidants. Compound 38 had a free phenolic group, yet the NO2 substituent in ortho-position strongly reduced its antioxidant potency. These results are in accordance with the theory of the lipid oxidation inhibition, namely, that the substitution of the phenolic rings is important to the antioxidant capacity of the compounds. Obviously, only compounds containing free phenolic groups in the aromatic nucleus are capable of clearing free radicals and shortening the lipid oxidation chain length. On the contrary, as there is no free phenolic group in the aromatic nucleus, the OH group from the 4-hydroxy-bis-coumarin does not have the ability of scavenging radicals. The molecule of the 4-hydroxy-bis-coumarin moiety without free phenolic groups in the aromatic nucleus is insignificant to the antioxidant and antiradical activity. There is a remarkable antioxidant effect of coumarins with C-4 methyl group. Pedersen et al. studied the free radicals scavenging activities of the 22 structurally related 4-methyl coumarins and found that ortho-dihydroxycoumarin (at 10 μmol/L) significantly reduced stress-induced intracellular production-ROS, the effect of which was stronger than with the meta-dihydroxy and monohydroxy substituted analogues. Moreover, ortho-diacetoxyl derivatives also have significant effects on free 14 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 15 Molecular Nutrition & Food Research radical scavenging. Since 4-methyl coumarins did not produce toxic epoxide intermediates in vivo, it was considered a promising antioxidant prodrug. A similar result was obtained by Roussaki et al. who synthesized and evaluated a series of coumarin analogues for their antioxidant and soybean lipoxygenase (LO) inhibitory activity through structural modifications on the coumarin scaffold. It has been revealed that 3-aryl-coumarin analogues bearing a bromine atom at C-6 position and a methyl group at C-4 position behave as potent inhibitors of LO. Prenyloxy-coumarins 39 and 40 (Fig. 11) exhibited the best combinatorially pharmacological characteristics, which efficiently suppressed lipid peroxidation and soybean LO. As for the chemical modifications of the 2-carbonyl group, compound 41 and 42 appropriately substituted by thiocoumarins are potential lipoxygenase inhibitors whereas the hydrazone analogues 43 and 44 are not active in LO inhibition but efficient as DPPH radical scavengers. Hence one can see that hydroxyl substitutions in the coumarin aromatic nucleus attach great significance on the antioxidant activity, especially o-DHC, followed by C-4 methyl groups. The free radicals take out a hydrogen atom from a group (usually hydroxyl) of antioxidant molecules to form phenoxy radicals, i.e. hydrogen atom transfer mechanism. One of the main pharmacological activities of coumarins is the removal of excess oxygen free radicals in vivo, of which the antioxidant effect is mainly through the hydrogen atom transfer mechanism to remove the body overfull oxygen free radicals. The coumarin monomer compounds in natural plants with obvious antioxidant effects have strong activities of the inhibition of xanthine oxidase, the protection of light damage and the scavenging of oxygen free radicals. Table 3 lists the antioxidative effects and mechanisms of natural coumarin active ingredients studied in recent years. Antioxidant activities are not always directly relevant in vivo as the glutathione (GSH)/ oxidized glutathione (GSSH) systems normally take care of the potential. However they affect pathways in more indirect ways. Like the quercetin blocks H2O2-decreased total intracellular GSH and JNK and p38 MAPK phosphorylation, daphnetin (83) effectively inhibited apoptosis, cytotoxicity, and mitochondrial dysfunction, which is related to the 15 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 16 Molecular Nutrition & Food Research suppressed ROS generation, increased superoxide dismutase (SOD) levels and GSH/ GSSH ratio etc. This may be involved in the activation of JNK and ERK by the upregulation of Nrf2 antioxidant signaling pathways to protect the oxidative damage and mitochondrial dysfunction triggered by tert-butyl hydroperoxide. 3.4 Antimicrobial activity The antibacterial properties of coumarins were first recognized in 1945. Dicoumarol was found to inhibit the growth of several strains of bacteria. Bacteriostatic drugs can usually affect spore germination, mycelial growth and the formation of various fruiting bodies. It has been demonstrated that the nature and position of substituent groups can determine the increased or decreased antibacterial activity for these compounds. Particularly, many studies have shown that the substitution on the coumarin aromatic ring effects the antibacterial activity. The C-7 free hydroxyl group in the coumarin parent nucleus is important for its anti-bacterial activity, and a C-6 free hydroxyl group is necessary for antifungal activity. However, studies have shown that C-6 free hydroxyl group is also necessary for anti-bacterial activity. The free hydroxyl group at the C-6 position or C-8 position endows the coumarin with broad-spectrum antimicrobial activity in the presence of a C-7 methoxy group. The antibacterial activity of free hydroxycoumarin may be related to the removal of free radicals from the phenolic hydroxyl structure. As for the antifungal activities of coumarins, it was confirmed that 4-hydroxycoumarin had no antifungal activity. Among many synthesized coumarins and angular furanocoumarins, the free 6-OH was found to be important for antifungal activityactivity, i.e.-the antifungal ability was significantly decreased when C-6 hydroxyl had a protective group. However, the free hydroxyl group at C-7 position in the coumarin parent nucleus is important for antibacterial activity. The antifungal activities of the 6, 7, 8-trisubstituted coumarins are connected the polarity of the C-8 position substituent. 16 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 17 Molecular Nutrition & Food Research Antimicrobial activity of the 3-ethylamino-coumarin (45) (Fig. 1) can be increased by the extension of the chain length of acyl groups. In vitro studies have shown that superior antibacterial activity of the compounds demand them to be fat-soluble (passive diffusion into the bacteria) and have a planar structure and avoiding long-chain structure (assists compounds to enter the bacterial cell wall). Okamoto et al. synthesized 28 kinds of osthole derivatives, and three compounds screened had significantly inhibited the Con-A-induced increase of the plasma alanine aminotransferase .  Osthole (23) provided anti-hepatitis C virus activity. Using mice Con A-induced hepatitis at 100 mg•kg-1 dose of intraperitoneal injection of Osthole (23), the inhibition rate was 85% on Con A-induced elevation of plasma ALT. Osthenol (46) (Fig. 1) showed an inhibition rate of 32% and 7-hydroxycoumarins inhibition rate was 9%. It verified that the methoxy group at the 7-position and the 3-methyl-2-butenyl group at the 8-position were necessary for the activity of osthole (23). Many synthetic compounds with similar structures of the osthole exhibit anti-hepatitis C virus activity. And some 7-propyloxy derivatives with similar structures to osthole (23) also exhibited an inhibitory activity on hepatitis C virus and hepatitis C related viruses. In a study of bactericidal activity of 7-hydroxycoumarin derivatives, it was found that at the concentration of 50μg/mL, when the coumarin benzene ring had an allyl group, whether it was O-hydrocarbylation or rearranged, Rhizoctonia solani and Fusarium graminearum showed a good controlling effect. The inhibitory rate of 4, 8-dimethyl-7-allyl-coumarin and 4-methyl-6-chloro-7-hydroxy-8-allyl-coumarin on Rhizoctonia solani is more than 90%, suggesting that the coumarin benzene ring with an allyl group has a better bactericidal activity. Some of the natural 4-aryl coumarins exhibit antibacterial activity. For example, the minimum inhibitory concentrations of 5,7-dimethoxy-4-arylcoumarin and 5, 7-dimethoxycoumarin isolated from Streptomyces aureofaciens on the plant pathogenic fungi Collectotrichum musae were 120μg/mL 17 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 18 Molecular Nutrition & Food Research and 150μg/mL respectively. Mesuarin (47) (Fig. 4) isolated from Mesua ferrea is active against Bacillus firmis. Mesuagin (48) (Fig. 4), similar to the mesuarin (47) structure, can effectively inhibit the growth of Staphylococcus aureus. The antibacterial activity of containing a dihydroxyl on the aryl coumarin is stronger than that containing only a single hydroxyl on the aryl coumarin. Among the aryl-hydroxy-coumarins containing a single hydroxyl group, the antibacterial activity of the hydroxyl group at the 6-position is slightly stronger than that of the hydroxyl group at the 7-position. 4-arylcoumarin which contains the aryl group in the 3-position and a hydroxyl group in 4-position has a strong and a wide range of antibacterial activity. Song et al. first reported the antifungal properties of several new linear and angular pyranocoumarins, anomalin (49), disenecioyl khellactone (50) and peuformosin (51) (Fig. 6), which had high or weak antifungal activities against five plant pathogens. In particular, disenecioyl khellactone (50) revealed strong antifungal activity against S. sclerotiorum, T. cucumeris, B. cinerea and F. graminearum (EC50=29.1, 36.2, 11.0 and 40.1 μg/mL respectively). Pd-D-V (52) (Fig. 6), a linear pyranocoumarin, had preferential activity against S. sclerotiorum (EC50=13.2 μg/mL) and favorable effect against C. capsici, B. cinerea and F. graminearum (EC50 =37.3, 35.5 and 33.5μg/mL respectively). Another report indicated that decursin (53) and decursinol angelate (54) (Fig. 4) (linear pyranocoumarins isolated from A. gigas) can effectively restrain the rice blast by inhibiting the spore germination instead of the mycelial growth to M.oryzae. Furthermore, C-5 substituents have different effects on the antifungal activity of angular furanocoumarins. Libanorin (55), columbianedin (56) and columbianetin acetate (57) (Fig. 3), containing esters at their C-5 positions, showed higher antifungal activities than the columbianetin (58) (Fig. 3) that contained a hydroxyl group at its C-5 position correspondingly. Therefore, the C-5 position on the coumarin parent nucleus may be one of its antifungal active sites. Overall, free hydroxyl group in parent nucleus, C-3 acylamino group, C-4 aryl group, benzene ring with allyl substituent coumarins, osthole analogues and several linear and angular 18 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 19 Molecular Nutrition & Food Research pyranocoumarins, contribute to enhancing strong antimicrobial activities. Selected specific coumarin monomers derived from plants are summarized in Table 4. These call for further studies, where these coumarins can be examined as potential lead compounds for developing novel antimicrobial agents. The coumarins that inhibit the mycelial growth, spore production and spore germination may be work through the inhibition of bacterial glucose and calcium absorption, and destruction of a mycelial calcium ion gradient, resulting in the synthesis and the transport block of cell wall chitin. In addition, coumarins can also inhibit bacterial proliferation via inhibiting the catalytic activity of alkenyl acyl-ACP reductase (Fab I and Fab K). This is an enzyme that catalyzes the last step in the bacterial fatty acid synthesis pathway (FAS-II), a rate-limiting enzyme for the entire synthetic pathway, which has been identified as a target for antimicrobial agents. Potential novel coumarin antibiotics based on the natural product could be modified to further enhance their antimicrobial potency. 3.5 Anti-inflammatory analgesic activity At present, many studies have indicated that coumarins from plants have significant anti-inflammatory analgesic activities, such as imperatorin (59) (Fig. 2) from Radix Angelicae dahuricae, scopoletin (60) (Fig. 1) from Hypochaeris radicata.[80, 81] Six coumarins were isolated from Murraya paniculata leaves, which were osthole (23), phebalosin (61), meranzin (62), umbelliferone (63), scopoletin (60), murracarpin (64) (Fig. 1). Murracarpin (64) was found to have a strong anti-inflammatory analgesic activity, which may be related to its C-7 methoxyl group, C-8 short chain containing double bonds and alcohol hydroxyl. It was demonstrated that the substituents at the C-7 position were one of the conditions for the anti-inflammatory activity of coumarins. Furthermore, coumarins showed anti-inflammatory activities when the methoxyl groups were at the C-5 or C-7 position, short chain substitutions such as hydroxyl, oxygen or double bond were at the C-8 position. Anti-inflammatory and analgesic activities of coumarin compounds isolated from three species of genus Daphne were measured. The results showed that the 7-linked glycosides were 19 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 20 Molecular Nutrition & Food Research significantly anti-inflammatory while the 8-linked glycosides had no anti-inflammatory activity. 7-hydroxycoumarin had significant analgesic activity. Based on these results, 7, 8-disubstituted coumarins are compounds with anti-inflammatory and analgesic activities, and the 7, 8-position substituents are closely related to the specific activities. 7-subsituted coumarin derivatives were synthesized by various aromatic and heterocyclic amines, and their anti-inflammatory and analgesic activities in vivo were evaluated via the inhibition of the 5-lipoxygenase (5-LOX). It was revealed that compound 65 and 66 (Fig. 12) were the two of the most potent compounds in all the screening methods. Compound 66 showed mixed or non-competitive type of inhibition of 5-LOX in an in vitro kinetic study. Substitutions of -OCH3 group in 66 and -Cl in 65 at C-6 position of benzothiazole ring were found to be crucial for potent activity. The existence of a benzothiazole ring compared to the substituted phenyl ring with amino alcohol linker at C-7 position of coumarin ring played a critical role in interaction with 5-LOX enzyme in docking study as well as in all the pharmacological screening methods. Mohammed et al. designed and synthesized a new series of fused coumarin derivatives for the test of their inhibition effects towards LPS-induced NO and PGE2 productions in RAW 264.7 macrophages. Three promising NO production inhibitors, 67, 68 and 71 (Fig. 13), played a part in inhibiting the expression of iNOS protein, accompanied by an additional iNOS mRNA expression inhibition of compound 71. Bulkier rings fused on the coumarin nucleus were found more favorable for activity. The three compounds, especially the tetracyclic analog 71, was more potent than the previously reported tricyclic coumarin derivatives. The other two derivatives, 69 and 70, were inhibitors of PGE2 production via inhibiting the expression and activity of COX-2 enzyme. Moreover, compound 70 also displayed an inhibitory effect on COX-2 mRNA expression at 5 μM. Both of them have methoxycoumarin and para-toluenesulfonate moieties which may facilitate proper affinity and efficacy. The chloro and methoxy substituents on the coumarin nucleus generally enhanced the activity compared to the corresponding unsubstituted coumarin derivatives. The 20 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 21 Molecular Nutrition & Food Research cycloheptane ring was better for inhibiting PGE2 production than the bulkier cyclooctane or indene rings. Coumarins can inhibit the production of pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), IL-1β, NO, enhance the production of anti-inflammatory cytokine IL-10, and inhibit the production of pro-inflammatory mediators iNOS mRNA, cyclooxygenase-2 (COX-2) mRNA, and anti-inflammatory mediators HO-1 mRNA. The down-regulation of pro-inflammatory cytokines is mediated by the inhibition of nuclear factor-kB (NF-kB) and inhibitory factor-kB (I-kB), which have positive regulatory effects against inflammatory factors, indicating that their anti-inflammatory effects are attributed to a dual-phase regulatory mechanism of inhibition of the production of pro-inflammatory factors and the promotion of the formation of anti-inflammatory factors. The mechanism of analgesia is mainly related to its inhibition of the synthesis of NO. NO as an important biological activity molecule plays an important role in the pain modulation of the central and peripheral nervous system. The decrease of endogenous NO level in the central nervous system shows a certain analgesic effect. However, the inhibition of the NO synthesis can bring about the analgesic effect in the modulation of the peripheral pain. Table 5 summarizes the studies on natural coumarins involving anti-inflammatory and analgesic effects and mechanisms in recent years. The main active groups in the structure-activity relationships of the anti-inflammatory analgesic are C-5 and C-7 methoxy groups, C-7 hydroxyl, C-8 short chain substitutions such as hydroxyl, oxygen and double bond, o-DHC etc. It was observed that replacements of substituents in the coumarin positions C-5 and C-7 exhibited higher activity, which was considered in a QSAR study as the lead optimization in the design of coumarins as potent non-steroidal anti-inflammatory agents. 3.6 Anti-cardiovascular disease 21 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 22 Molecular Nutrition & Food Research Dyslipidemia characterized by abnormal blood lipid levels (i.e., cholesterol and fatty acids) and/or circulating lipoprotein abnormalities is one of the hazards factors for cardiovascular disease. Oxidative stress has been implicated in the pathogenesis of various illnesses including cardiovascular disease. The potential therapeutic or preventive effects of antioxidant agents have recently attracted great attention. Studies have shown that some coumarins have beneficial effects on cardiovascular disease, and the results of relevant recent studies are shown in Table 6. Khellactone derivatives (17), a new type of Ca2+ antagonist for expanding coronary arteries in the treatment of cardiovascular disease, have broad application prospects. The coumarins with the effect of treating cardiovascular diseases generally contain a khellactone structure. Pteryxin (72) (Fig. 6) isolated from the Umbelliferae Pteryxinterebinthina root has a strong effect of expanding coronary arteries, dilating blood vessels, lowering blood pressure, slowing down the frequency of heart systolic, and reducing cholesterol and lecithin. Suksdorfin (18) isolated from the Lumatium suksdorfin fruit has significant antispasmodic and coronary dilatation effects. A common feature of the above active ingredients is that C-3 and C-4 positions are cis-structures, which thus may be necessary for the dilation of coronary arteries. (+) Praeruptorin C (73) (Fig. 6) is an angular pyranocoumarin isolated from Peucedanum praeruptorum. In recent years, it has been found that praeruptorin C (73) has a prominent effect in lowering blood pressure and diastole of coronary arteries through Ca2+ antagonism. Wu et al. studied the structural modification of praeruptorin C (73) in order to explore its structure-activity relationships. They partially or fully hydrolyzed the two acyl groups of the praeruptorin C (73) in C-3 and C-4 positions to get one only-hydrolysed C-4 acetyl product and two fully hydrolysed products. The acylations of the total hydrolyzates were carried out by making use of the different conditions of the acylation reaction to change the structures of the C-3 and C-4 acyl groups. 15 new compounds were obtained and showed different degrees of Ca2+ antagonistic activity, but all were lower than those of praeruptorin C (73). 22 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 23 Molecular Nutrition & Food Research In 2003, structural modification of praeruptorin C (73) was carried out to synthesize 17 kinds of C-3' and C-4' trans-structures. Like praeruptorin C, some of the synthetic trans-khellactone coumarins also displayed significant Ca2+ antagonistic activity, and the highest inhibition rate on rat arterial ring contraction reached 62.40%. This report not only modified the view that the C-3', C-4' cis structure of khellactone coumarins was a necessary structure for Ca2+ antagonistic activity, but also amended some scholars’ statement that acetoxy was the necessary group of Ca2+ antagonist, which had provided an important reference for the subsequent research and development of khellactone coumarins. Furthermore, studies of the lipid-lowering effects of coumarins and their derivatives (esculetin (33), scoparone (74), and 4-methylumbelliferone (75) (Fig. 1) in rats indicated that 4-Methylumbelliferone had no recovery effects on serum TC(cholesterol) levels, but significantly prevented CCl4-induced hyperlipidemia by reducing triglyceride (TG) and very low-density lipoprotein cholesterol (VLDL-C) levels. In addition, most coumarins were confirmed to have no recovery effect on any of the lipid parameters against CCl4-induced hyperlipidemia in serum, only esculetin (33) and scoparone (74) with no methyl at C-4 position could prevent HDL-C in CCl4-induced dyslipidemia. The results indicate that the chemical structure of coumarins is of great importance to the regulation of serum lipid profiles. Hybridization of the coumarin with the indole moiety, present in various synthetic statins such as fluvastatin, has generated the coumarin-indole compound. Compound 76 (Fig. 1) had potent antihyperlipidemic activity among the 12 tested compounds, which significantly decreased the plasma TG levels by 55% and TC levels by 20%, meanwhile, increased the HDL-C/TC ratio by 42% in hyperlipidemic rats. The research group has also synthesized coumarin-chalcone fibrates that are found to reverse the triton-induced increase in plasma lipid levels. These hybrids inhibited the biosynthesis of TC and enhanced the activity of lipolytic enzyme and lipoprotein lipase, facilitated early clearance of lipids from circulation in triton-induced hyperlipidemia. Compound 77 (Fig. 1) 23 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 24 Molecular Nutrition & Food Research showed the highest percentage of 26%, 24% and 25% in lowering in TC, PL and TG levels at the dose of 100 mg/kg, respectively. Natural coumarins can block the calcium influx and open potassium channels involved in cardiovascular disease. Calcium flow obstruction and potassium channel opening both can relieve the cytoplasmic Ca2+ overload, maintain intracellular and extracellular calcium balance and mitochondrial stability, resulting in antihypertensive, antiarrhythmic, negative inotropic effects and other biological effects.[94, 98] Altogether, khellactone derivatives (17) are a class of major compounds against cardiovascular disease among coumarins, of which the other two categories are coumarin-indole compounds and coumarin-chalcone fibrates. It is suggested that these natural coumarins and novel hybrids will be a potential new class of therapeutic agents against cardiovascular disease. 3.7 The electronic and steric effect An important method which can be applied to develop new drugs is computer-assisted drug design (CADD). The method involves traditional or classic QSAR and 3D QSAR. The chemical structure can be described with experimental and theoretical steric, electronic, and hydrophobic parameters for QSAR. It presents the electronic or steric (spatial) effects in the coumarins molecules studied.[102, 103] Fig. 14 shows the pharmacological effects and structure-activity relationships of the coumarins mentioned in the text. Research has suggested that DCK analogues can remarkably decrease the HIV-1 replication in H9 lymphocytes, and 5-methoxy-4-methyl DCK is the most promising structure. Conformational analysis indicated that the resonance of the coumarin system is a vital structural feature of the potent anti-HIV activity. The spatial compression of the C-4 and C-5 substituents in coumarins can reduce the overall planarity and bring about the resonance of the coumarin parent nucleus, resulting in reduction or lack of anti-HIV activity. Among the series of tested coumarins, the most active scavengers were the hydrazone analogues 43 and 44 with the 84–86% DPPH scavenging ability compared to that of the positive control nordihydroguaiaretic acid (84%). This 24 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 25 Molecular Nutrition & Food Research phenomenon was attributed to the extended conjugation system of the benzhydrazone group that could increase the ability of the coumarin radical, of which the conjugated system were formed after H transfer from the DPPH radical, to accommodate the free electron. The substitution of alkyl groups at the C-6 position in coumarins commonly decreases the anti-inflammatory activity, except a methyl group. Some aspects of the electronic effects of these substitutions are not clear. TNF-α inhibitory activities can be improved or diminished by the substitutions of electron-withdrawing groups such as CHO, CN, NO2 and COOH, whereas electron-donating groups like OCH3 increased the activity by threefold similar to the CN group. The C-6 position of the coumarin-chalcone fibrates in the benzopyran moiety substituted with the strong electron-withdrawing nitro group is more stable than electron-donating groups, halogens, and sterically-hindered groups, which is consistent with previous reports that chalcone fibrate with a nitro group was a very potent antidyslipidemic agent. 4. Conclusion and perspectives The physiological activities of coumarins are closely related to their chemical structure characteristics. The basic parent nucleus, substituents, substitution patterns and substitution numbers of coumarins may have a significant effect on their pharmacological activities. Currently, structural modifications of coumarins are mostly concentrated on the benzene ring, a little less on the α-pyrone, via introducing a variety of different substituents such as hydroxyl, methoxyl, methylene-dioxy, isopentenyl, and aryl groups to improve their bioactivities. It turns out that the o-DHC on benzene ring has remarkable antioxidant and anti-tumor activities through scavenging free radicals. The free hydroxyl groups are effective against the inflammation, pain, and pathogenic microorganisms. The presence of aryl groups at the nucleus of coumarin is significant for several biological activities. Coumarins with aryl groups at the C-4 position have good anti-HIV, anti-tumor, anti-inflammatory, and analgesic activities. C-3 phenylcoumarins have a highly beneficial effect against HIV and oxidation. In addition, some specific classes of coumarin have specific efficiency, for example, 25 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 26 Molecular Nutrition & Food Research tetracycline pyranocoumarins can significantly inhibit HIV, osthol structural analogues have antimicrobial activity, praeruptorin C and its derivatives play a prominent role in lowering blood pressure and dilating coronary arteries, and khellactone derivatives can remarkably react on AIDS, cancer and cardiovascular disease. A summary of pharmacological activities of main coumarins discussed in this article is listed in Table 7. This review is an attempt to address the potential vista of the strategically placed coumarin scaffold in pharmaceutical chemistry, which can be used to further investigate in order to facilitate the use of its maximum potential. It is conducive for the rational design and development of more active and less toxic drugs with a coumarin scaffold. Owing to the precise planarity and flexibility, the coumarin nucleus can be seamlessly designed to target specific receptors or can also be used to target multiple sites utilizing a synergistic reaction. This review should provide a new perspective for the study of coumarin-derived drugs and get better access to the function of these molecules in diseases. The study of the clinical application of coumarins, the elucidation of pharmacological mechanisms, the exploration of structure-activity relationships and the structural modifications may open up fresh important avenues for further rational application and development of related novel drugs. 5 References  Sairam, K. V., Gurupadayya, B. M., Chandan, R. S., Nagesha, D. K., Vishwanathan, B., A review on profile of coumarins and their therapeutic role in the treatment of cancer. Curr. Drug. Deliv. 2016, 13, 186-201.  Kostova, I., Studying plant-derived coumarins for their pharmacological and therapeutic properties as potential anticancer drugs. Expert. Opin. Drug. Dis. 2007, 2, 1605-1618.  Kim, H. J., Yu, Y. G., Park, H., Lee, Y. S., HIV gp41 binding phenolic components from Fraxinus var. angustata. Planta. Med. 2002, 68, 1034-1036. 26 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 27 Molecular Nutrition & Food Research  Hu, R., Li, Z. L., Yang, L., Yang, J. R., Anti-inflammatory activities of imperatorin from Radix Angelicae dahuricae extract on acute pleurisy in rats. Chin. Med. Emerg. 2012, 04, 576-577.  Venugopala, K. N., Rashmi, V., Odhav, B., Review on natural coumarin lead compounds for their pharmacological activity. Biomed. Res. Int. 2013.  Li, Y. Y., Cai, X. D., Advances in pharmacology of coumarins. Chin. Herb. Med. 2004, 03, 218-222.  Wu, L., Wang, X., Xu, W., Farzaneh, F., Xu, R., The structure and pharmacological functions of coumarins and their derivatives. Curr Med Chem 2009, 16, 4236-4260.  Kong, L. L., Hu, J. F., Chen, N. H., Advances in pharmacological and toxicological effects of coumarins. Pharmacol. Bull. 2012, 19, 3884-3930.  Peng, X. M., Damu, G. L. V., Zhou, C. H., Current developments of coumarin compounds in medicinal chemistry. Curr Pharm Design 2013, , 3884-3930.  Iranshahi, M., Askari, M., Sahebkar, A., Hadjipavlou-Litina, D., Evaluation of antioxidant, anti-inflammatory and lipoxygenase inhibitory activities of the prenylated coumarin umbelliprenin. J. Pharm. Sci. 2009, 17, 99-103.  Mohamed, T. K., Chemical constituents and antioxidant activity of Citrus paradisi (star-ruby red grapefruit) and Citrus sinensis (blood sweet orange) Egyptian cultivars. Asian. J. Chem. 2004, 16, 1753-1764.  Zhang, X. L., Synthesis and Bioactivity of Coumarin Derivatives. Zhengzhou. Univ. 2012.  Musa, M. A., Cooperwood, J. S., Khan, M. O. F., A review of coumarin derivatives in pharmacotherapy of breast cancer. Curr. Med. Chem. 2008, 15, 2664-2679.  Song, Y. L., Jing, W. H., Du, G., Yang, F. Q., Yan, R., Wang, Y. T., Qualitative analysis and determination of angular-type pyranocoumarins in Peucedani Radix using achiral and chiral liquid chromatography coupled with tandem mass spectrometry. J. Chromatogr. A. 2014, 1338, 24-37.  Fu, T. T., Ni, M. X., Development of nucleoside anti-AIDS drugs. Prog Pharm Sci 2007, 05, 211-216. 27 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 28 Molecular Nutrition & Food Research  Hayashi, T., M. Jean, M., Huang, H. C., Simpson, S., Santoso, N. G., Zhu, J., Screening of an compound library identifies levosimendan as a novel anti-HIV-1 agent that inhibits viral transcription. Antiviral. Res. 2017, 146, 76-85.  Ghare, S. S., Donde, H., Chen, W. Y., Barker, D. F., Gobejishvilli, L., McClain, C. J., Barve, S. S., Joshi-Barve, S., Acrolein enhances epigenetic modifications, FasL expression and hepatocyte toxicity induced by anti-HIV drug Zidovudine. Toxicol. In. Vitro. 2016, 35, 66-76.  Kashman, Y., Gustafson, K. R., Fuller, R. W., Cardellina, J. H., McMahon, J. B., Currens, M. J., Buckheit, W. J., Hughes, S. H., Cragg, G. M., Boyd, M. R., The calanolides, a novel HIV-inhibitory class of derivatives from the tropical rainforest tree, Calophyllum lanigerum. J Med Chem 1992, 35, 2735-2743.  César, G. Z. J., Alfonso, M. G. G., Marius, M. M., Elizabeth, E. M., Angel, C. B. M., Maira, H. R., Guadalupe, C. L. M., Manuel, J. E., Ricardo, R. C., Inhibition of HIV-1 reverse transcriptase, toxicological and chemical profile of Calophyllum brasiliense extracts from Chiapas, Mexico. Fitoterapia. 2011, 82, 1027-1034.  Kostova, I., Coumarins as inhibitors of HIV reverse transcriptase. Curr HIV Res 2006, 4, 347-363.  Buckheit, R. W., White, E. L., Fliakas-Boltz, V., Russell, J., Stup, T. L., Kinjerski, T. L., Osterling, M. C., Weigand, A., Bader, J. P., Unique anti-human immunodeficiency virus activities of the nonnucleoside reverse transcriptase inhibitors calanolide A, costatolide, and dihydrocostatolide. Antimicrob. Agents. Chemother. 1999, 43, 1827-1834.  Gu, Q., Zhang, X. M., Wang, R. R., Liu, Q. M., Zheng, Y. T., Zhou, J., Chen, J. J., Anti-HIV Active Constituents from Angelica apaensis. Nat. Pro. Res. Dev. 2008, 20.  Ong, E. B. B., Watanabe, N., Saito, A., Futamura, Y., K.H. Abd El Galil, Koito, A., Najimudin, N., Osada, H., Vipirinin, a coumarin-based HIV-1 Vpr inhibitor, interacts with a hydrophobic region of Vpr. J. Bio. Chem. 2011, 286, 14049-14056.  Srivastav, V. K., Tiwari, M., QSAR and docking studies of coumarin derivatives as potent HIV-1 integrase inhibitors. Arabian. J. Chem. 2017, 10, 1081-1094. 28 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 29 Molecular Nutrition & Food Research  Srivastav, V. K., Tiwari, M., QSAR and docking studies of coumarin derivatives as potent HIV-1 integrase inhibitors. Arab. J. Chem. 2013, 10, 1081-1094.  Dong, B., Ma, T., Zhang, T., Zhou, C. M., Liu, G., Wang, L., Tao, P. Z., Zhang, X. Q., The inhibitory and its structure-activity relationship of pyranocoumarins on HIV-1 virus. Acta. Pharm. Sin. 2011, 01,  Patil, A. D., Freyer, A. J., Eggleston, D. S., Haltiwanger, R. C., Bean, M. F., Taylor, P. B., Caranfa, M. J., Breen, A. L., Bartus, H. R., The inophyllums, novel inhibitors of HIV-1 reverse transcriptase isolated from the Malaysian tree, Calophyllum inophyllum Linn. J. Med. Chem. 1993, 36, 4131-4138.  Currens, M. J., Gulakowski, R. J., Mariner, J. M., Moran, R. A., Buckheit, R. W. J., Gustafson, K. R., McMahon, J. B., Boyd, M. R., Antiviral activity and mechanism of action of calanolide A against the immunodeficiency virus type-1. J Pharmacol Exp Ther 1996, 279, 645-651.  Lee, T. T., Kashiwada, Y., Huang, L., Snider, J., Cosentino, M., Lee, K. H., Suksdorfin: an anti-HIV from Lomatium suksdorfii, its structure-activity correlation with related coumarins, and synergistic effects with anti-AIDS nucleosides. Bioorg. Med. Chem. 1994, 2, 1051-1056.  Huang, L., Kashiwada, Y., Cosentino, L. M., Fan, S., Chen, C. H., Andrew, T., Fujioka, T., Mihashi, K., K. H., Anti-AIDS agents. 15. Synthesis and anti-HIV activity of dihydroseselins and related analogs. J. Chem 1994, 37, 3947-3955.  Xie, L., Takeuchi, Y., Cosentino, L. M., Lee, K. H., Anti-AIDS agents. 37. Synthesis and structure-activity relationships of (3'R, 4'R)-(+)-cis-khellactone derivatives as novel potent anti-HIV agents. J. Med. Chem. 1999, 42, 2662-2672.  Takeuchi, Y., Xie, L., Cosentino, L. M., Lee, K. H., Anti-AIDS agents-XXVIII. Synthesis and Anti-HIV activity of methoxy substituted 3', 4'-Di-O-(-)-camphanoyl-(+)-cis-khellactone (DCK) analogues. Bioorg. Med. Chem. Lett. 1997, 7, 2573-2578.  Guo, N., Wu, J., Fan, J., Yuan, P., Shi, Q., Jin, K., Cheng, W., Zhao, X., Zhang, Y., In vitro activity of isoimperatorin, alone and in combination, against Mycobacterium tuberculosis. Lett. Appl. Microbiol. 2014, 58, 344-349. 29 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 30 Molecular Nutrition & Food Research  Braccio, M. D., Grossi, G., Roma, G., Signorello, M. G., Leoncini, G., Synthesis and in vitro inhibitory activity on human platelet aggregation of novel properly substituted 4-(1-piperazinyl) coumarins. Eur. J. Med. Chem. 2004, 39, 397-409.  Goel, A., Prasad, A. K., Parmar, V. S., Ghosh, B., Saini, N., 7,8-Dihydroxy-4-methylcoumarin induces apoptosis of human lung adenocarcinoma cells by ROS-independent mitochondrial pathway through partial inhibition of ERK/MAPK signaling. FEBS. Lett. 2007, 581, 2447-2454.  Riveiro, M. E., Vazquez, R., Moglioni, A., Gomez, N., Baldi, A., Davio, C., Shayo, C., Biochemical mechanisms underlying the pro-apoptotic activity of 7, 8-dihydroxy-4-methylcoumarin in human leukemic cells. Bio. Pharm. 2008, 75, 725-736.  Vazquez, R., Riveiro, M. E., Vermeulen, M., Alonso, E., Mondillo, C., Facorro, G., Piehl, L., Gomez, N., Moglioni, A., Fernandez, N., Structure-anti-leukemic activity relationship study of ortho-dihydroxycoumarins in U-937 cells: Key role of the δ-lactone ring in determining differentiation-inducing potency and selective pro-apoptotic action. Bioorg Med Chem 2012, 20,  Beillerot, A., Dominguez, J. C. R., Kirsch, G., Bagrel, D., Synthesis and protective effects of coumarin derivatives against oxidative stress induced by doxorubicin. Bioorg Med Chem Lett 2008, 18, 1102-1105.  Lin, M. H., Cheng, C. H., Chen, K. C., Lee, W. T., Wang, Y. F., Xiao, C. Q., Lin, C. W., Induction of ROS-independent JNK-activation-mediated apoptosis by a novel coumarin-derivative, DMAC, in human colon cancer cells. Chem. Biol. Interact. 2014, 218, 42-49.  Gacche, R. N., Jadhav, S. G., Antioxidant activities and cytotoxicity of selected coumarin derivatives: Preliminary results of a structure-activity relationship study using computational tools. J Exp Clin Med 4, 165-169.  Serra, S., Chicca, A., Delogu, G., Vazquez-Rodriguez, S., Santana, L., Uriarte, E., Casu, L., Gertsch, J., Synthesis and cytotoxic activity of non-naturally substituted 4-oxycoumarin derivatives. Bioorg Med Chem Lett 2012, 22, 5791-5794. 30 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 31 Molecular Nutrition & Food Research  Riviere, C., Goossens, L., Pommery, N., Fourneau, C., Delelis, A., Henichart, J. P., Antiproliferative effects of isopentenylated coumarins isolated from Phellolophium madagascariense Baker. Nat. Prod. Res. 2006, 20, 909-916.  Jun, M., Bacay, A. F., Moyer, J., Webb, A., Carrico-Moniz, D., Synthesis and biological evaluation of isoprenylated coumarins as potential anti-pancreatic cancer agents. Bioorg. Med. Chem. Lett. 2014, 24, 4654-4658.  Wu, J. Y. C., Fong, W. F., Zhang, J. X., Leung, C. H., Kwong, H. L., Yang, M. S., Li, D., Cheung, H. Y., Reversal of multidrug resistance in cancer cells by pyranocoumarins isolated from Radix Peucedani. Eur. J. Pharmacol. 2003, 473, 9-17.  Shen, X. L., Chen, G. Y., Zhu, G. Y., Fong, W. F., (±)-3'-O, 4'-O-dicynnamoyl-cis-khellactone, a derivative of (±)-praeruptorin A, reverses P-glycoprotein mediated multidrug resistance in cancer cells. Bioorg. Med. Chem. 2006, 14, 7138-7145.  Fong, W. F., Shen, X. L., Globisch, C., Wiese, M., Chen, G. Y., Zhu, G. Y., Yu, Z. L., Tse, A. K. W., Hu, J., Methoxylation of 3', 4'-aromatic side chains improves P-glycoprotein inhibitory and multidrug reversal activities of 7, 8-pyranocoumarin against cancer cells. Bioorg. Med. Chem. 2008, 16, 3694-3703.  Shen, X. L., Chen, G. Y., Zhu, G. Y., Cai, J. Z., Wang, L., Hu, Y. J., Fong, W. F., 3'-O, 4'-O-aromatic acyl substituted 7, 8-pyranocoumarins: a new class of P-glycoprotein modulators. J. Pharm. Pharmacol. 2012, 64, 90-100.  Lv, N., Sun, M., Liu, C., Li, J. B., Design and synthesis of 2-phenylpyrimidine coumarin derivatives as anticancer agents. Bioorg. Med. Chem. Lett. 2017, 27, 4578-4581.  Lee, S., Sivakumar, K., Shin, W. S., Xie, F., Wang, Q., Synthesis and anti-angiogenesis activity of derivatives. Bioorg. Med. Chem. Lett. 2006, 16, 4596-4599.  Chuang, J. Y., Huang, Y. F., Lu, H. F., Ho, H. C., Yang, J. S., Li, T. M., Chang, N. W., Chung, J. G., Coumarin induces cell cycle arrest and apoptosis in human cervical cancer HeLa cells through a 31 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 32 Molecular Nutrition & Food Research mitochondria- and caspase-3 dependent mechanism and NF-kappa B down-regulation. In. vivo 2007, 21, 1003-1009.  Reddy, N. S., Gumireddy, K., Mallireddigari, M. R., Cosenza, S. C., Venkatapuram, P., Bell, S. C., Reddy, P., Reddy, M. V. R., Novel coumarin-3-(N-aryl)carboxamides arrest breast cancer cell growth by inhibiting ErbB-2 and ERK1. Bioorg. Med. Chem. 2005, 13, 3141-3147.  Shen, C. Y., Jiang, J. G., Yang, L., Wang, D. W., Zhu, W., Anti-ageing active ingredients from herbs and nutraceuticals used in traditional Chinese medicine: pharmacological mechanisms and implications for discovery. Bri. J. Pharmacol. 2016.  G.L.Xi, Liu, Z. Q., Coumestan inhibits radical-induced oxidation of DNA: is hydroxyl a necessary group. J. Agr. Food. Chem. 2014, 62, 5636-5642.  Feng, J. F., Zhao, Q., Wei, X. M., Gou, Q. F., Chen, F. Z., Isolation, identification and antioxidant activity 6,7-dihydroxycoumarin in Semen Euphorbiae Lathyridis. Oils. Foods. 2015, 03, 32-35.  Martin-Aragon, S., Villar, A., Benedi, J., Age-dependent effects of esculetin on mood-related behavior and cognition from stressed mice are associated with restoring brain antioxidant status. Prog. Neuro-Psychoph. Biol. Psy. 2016, 65, 1-16.  Zhang, H. Y., Wang, L. F. T., THEOCHEM heoretical elucidation of structure-activity relationship for coumarins to scavenge peroxyl radical. J Mol Struct 2004, 673, 199-202.  Thuong, P. T., Hung, T. M., Ngoc, T. M., Ha, D. T., Min, B. S., Kwack, S. J., Kang, T. S., Choi, J. S., Bae, Antioxidant Activities of Coumarins from Korean Medicinal Plants and their Structure-Activity Relationships. Phytother. Res. 2010, 24, 101-106.  Kancheva, V. D., Boranova, P. V., Nechev, J. T., Manolov, I. I., Structure-activity relationships of new 4-hydroxy bis-coumarins as radical scavengers and chain-breaking antioxidants. Biochimie 2010, 92, 1138-1146. 32 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 33 Molecular Nutrition & Food Research  Pedersen, J. Z., Oliveira, C., Incerpi, S., Kumar, V., Fiore, A. M., De, V. P., Prasad, A. K., Malhotra, S. V., Parmar, V. S., Saso, L., Antioxidant activity of 4-methylcoumarins. J Pharm Pharmacol 2007, 59, 1721-1728.  Roussaki, M., Kontogiorgis, C. A., Hadjipavlou-Litina, D., Hamilakis, S., Detsi, A., A novel synthesis of 3-aryl coumarins and evaluation of their antioxidant and lipoxygenase inhibitory activity. Bioorg. Med. Chem. Lett. 2010, 20, 3889-3892.  Roussaki, M., Zelianaios, K., Kavetsou, E., Hamilakis, S., Hadjipavlou-Litina, D., Kontogiorgis, C., Liargkova, T., Detsi, A., Structural modifications of coumarin derivatives: Determination of antioxidant lipoxygenase (LOX) inhibitory activity. Bioorg. Med. Chem. Lett. 2014, 22, 6586-6594.  Luo, C., Zhou, D., Lu, X. X., Research Progress of Antioxidant Mechanism of Natural Products. Food. Sci. Technol. 2009, 04, 335-339.  Bacal, M., Wada, M., Negative hydrogen ion production mechanisms. Appl. Physics. Rev. 2015, 2, 021305.  Kerimi, A., Williamson, G., At the interface of antioxidant signalling and cellular function: Key polyphenol effects. Mol. Nutr. Food. Res. 2016, 60, 1770-1788.  Lv, H. M., Liu, Q. M., Zhou, J. F., Tan, G. Y., Deng, X. M., Ci, X. X., Daphnetin-mediated Nrf2 signaling pathways ameliorate tert-butyl hydroperoxide (t-BHP)-induced mitochondrial dysfunction and death. Free. Radical. Bio. Med. 2017, 106, 38-52.  Smyth, T., Ramachandran, V. N., Smyth, W. F., A study of the antimicrobial activity of selected naturally occurring and synthetic coumarins. Int. J. Antimicrob. Ag. 2009, 33, 421-426.  Han, S. Q., Yang, Y., Huang, T., Nie, J. R., Shi, D. F., Study on bacteriostasis mechanism of cactus extract. Food. Sci. Technol. 2007, 03, 130-134.  Kayser, O., Kolodziej, H., Antibacterial activity of simple coumarins: structural requirements for biological activity. Z. Naturforsch. C. 1999, 54, 169-174. 33 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 34 Molecular Nutrition & Food Research  Sardari, S., Mori, Y., Horita, K., Micetich, R. G., Nishibe, S., Daneshtalab, M., Synthesis and antifungal activity of coumarins and angular furanocoumarins. Bioorg Med Chem 1999, 7, 1933-1940.  Rauckman, B. S., Tidwell, M. Y., Johnson, J. V., Roth, B., 2, 4-Diamino-5-benzylpyrimidines and as antibacterial agents. 10. 2, 4-Diamino-5-(6-quinolylmethyl)-and-[(tetrahydro-6-quinolyl) methyl] pyrimidine derivatives. J Med Chem 1989, 32, 1927-1935.  Okamoto, T., Kobayashi, T., Synthetic derivatives of osthole for the prevention of hepatitis. Med. Chem. 2007, 3, 35-44.  Mazzei, M., Nieddu, E., Miele, M., Balbi, A., Ferrone, M., Fermeglia, M., Mazzei, M. T., Pricl, S., Colla, L., Marongiu, F., Activity of Mannich bases of 7-hydroxycoumarin against Flaviviridae. Bioorg Med Chem 2008, 16, 2591-2605.  Tan, Y. L., Synthesis and bactericidal activity of 7 - hydroxycoumarin derivatives. Nanjing. Agr. Univ.  Taechowisan, T., Lu, C. H., Shen, Y. M., Lumyong, S., 4-Arylcoumarins from endophytic Streptomyces aureofaciens CMUAc130 and their antifungal activity. Ann. Microbiol. 2005, 55, 63-66.  Sun, J., Ding, W. X., Zhang, K. Y., Zou, Y., Efficient synthesis and biological evaluation of 4-arylcoumarin derivatives. Chinese. Chem. Lett. 2011, 22, 667-670.  Song, P. P., Zhao, J., Liu, Z. L., Duan, Y. B., Hou, Y. P., Zhao, C. Q., Wu, M., Wei, M., Wang, N. H., Lv, Evaluation of antifungal activities and structure-activity relationships of coumarin derivatives. Pest. Sci. 2017, 73, 94-101.  Daoubi, M., Duran-Patron, R. D., Hmamouchi, M., Hernandez-Galan, R., Benharref, A., Collado, I. G., Screening study for potential lead compounds for natural product-based fungicides: I. Synthesis and in evaluation of coumarins against Botrytis cinerea. Pest. Manag. Sci. 2004, 60, 927-932.  Shi, Z. Q., Shen, S. G., Zhou, W., Wang, F., Fan, Y. J., Fusarium graminearum growth inhibition due to glucose starvation caused by osthol. Int. J. Mol. Sci. 2008, 9, 371-382. 34 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 35 Molecular Nutrition & Food Research  Liu, G. L., Study on the synthesis, insecticidal and antimicrobial activity of coumarins. Northwest. A&F. Univ. 2016.  Wang, K. S., Lv, Y., Wang, Z., Ma, J., Mi, C. L., Li, X. Z., Xu, G. H., Piao, L. X., Zheng, S. Z., Jin, X. J., Imperatorin efficiently blocks TNF-α-mediated activation of ROS/PI3K/Akt/NF-kB pathway. Oncol. Rep. 2017, 37, 3397-3404.  Senguttuvan, J., Krishnamoorthy, K., Subramaniam, P., Krishnaswamy, T., Subramanium, K., Rajendran, Confertin and scopoletin from leaf and root extracts of Hypochaeris radicata have anti-inflammatory and antioxidant activities. Ind. Crop. Prod. 2015, 70, 221-230.  Wu, L. H., Liu, S. W., Zeng, J., Xu, R. A., Anti-inflammatory and analgesic activity of coumarins in paniculata leaf. . Chin. J. Spectros. Lab. 2011, 06, 2999-3003.  Kontogiorgis, C. A., Hadjipavlou-Litina, D. J., Synthesis and biological evaluation of novel coumarin derivatives with a 7-azomethine linkage. Bioorg Med Chem Lett 2004, 14, 611-614.  Nakamura, T., Kodama, N., Oda, M., Tsuchiya, S., Arai, Y., Kumamoto, T., Ishikawa, T., Ueno, K., Yano, The structure-activity relationship between oxycoumarin derivatives showing inhibitory effects on iNOS in mouse macrophage RAW264.7 cells. J Nat Med 2009, 63, 15-20.  Zhang, W., Study on the active constituents of three kinds of Daphne medicinal plants. Second. Mil. Med. Univ. 2006.  Srivastava, P., Vyas, V. K., Variya, B., Patel, P., Qureshi, G., Ghate, M., Synthesis, anti-inflammatory, analgesic, 5-lipoxygenase (5-LOX) inhibition activities, and molecular docking study of 7-substituted coumarin derivatives. Bioorg. Chem. 2016, 67, 130-138.  El-Gamal, M. I., Lee, W. S., Shin, J. S., Oh, C. H., Lee, K. T., Choi, J., Myoung, N., Baek, D., Synthesis of New Tricyclic and Tetracyclic Fused Coumarin Sulfonate Derivatives and Their Inhibitory Effects on LPS-Induced Nitric Oxide and PGE(2) Productions in RAW 264.7 Macrophages: Part 2. Archiv. Der. Pharmazie. 2016, 349, 853-863. 35 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 36 Molecular Nutrition & Food Research  Jang, H. L., El-Gamal, M. I., Choi, H. E., Choi, H. Y., Lee, K. T., Oh, C. H., Synthesis of tricyclic fused coumarin sulfonates and their inhibitory effects on LPS-induced nitric oxide and PGE(2) productions in RAW 264.7 macrophages. Bioorg. Med. Chem. Lett. 2014, 24, 571-575.  Zhang, X. Y., Tao, J. Y., Zhao, L., Huang, Z. J., Xiong, F. L., Zhang, S. L., Li, C. M., Xiao, F., In vitro anti-inflammatory effects ethanol extract from of different solution fractions of Melilotus suaveolens Chin. Med. J. 2007, 120, 1992-1998.  Wang, H. L., Wang, C. M., Li, H., Cui, X. Y., Positions and mechanisms of analgesic effect of the from Radix Angelicae dahuricae. Chin. J. Gerontol. 2009, 15, 1902-1904.  Barot, K. P., Jain, S. V., Kremer, L., Singh, S., Ghate, M. D., Recent advances and therapeutic journey of coumarins: current status and perspectives. Med. Chem. Res. 2015, 24, 2771-2798.  Wu, R. R., Zhang, F. Y., Gao, K. M., Ou', J. J., Shao, P., Jin, H., Guo, W. B., Chan, P. K., Zhao, J. P., Metformin treatment of antipsychotic-induced dyslipidemia: an analysis of two randomized, placebo-controlled trials. Mol. Psychiatry. 2016, 21, 1537.  Tejada, S., Martorell, M., Capo, X., Tur, J. A., Pons, A., Sureda, A., Coumarin and Derivates as Lipid Lowering Agents. Curr. Topi. Med. Chem. 2017, 17, 391-398.  Song, Y. L., Jing, W. H., Zhao, H. Y., Yan, R., Li, P. T., Wang, Y. T., Stereoselective metabolism of (±)-praeruptorin A, a calcium channel blocker from Peucedani Radix, in pooled liver microsomes of rats humans. Xenobiotica 2012, 42, 231-237.  Chen, I. S., Chang, C. T., Sheen, W. S., C.M. Teng, Tsai, I. L., Duh, C. Y., Ko, F. N., Coumarins and antiplatelet aggregation constituents from formosan Peucedanum japonicum. Phytochemistry 1996, 41, 525-530.  Wenjie, W., Houqing, L., Liming, S., Effects of praeruptorin C on blood pressure and expression of phospholamban in spontaneously hypertensive rats. Phytomedicine 2014, 21, 195-198. 36 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 37 Molecular Nutrition & Food Research  Wu, X. L., Kong, L. Y., Min, Z. D., Study on the structural modification of praeruptorin C. Acta Pharm Sin 2002, 07, 527-534.  Kong, L. Y., Wu, X. L., Min, Z. D., Semi-synthesis of Praeruptorin C C-3' and C-4' trans structures. Acta. Pharm. Sin. 2003, 38, 358-363.  Tasdemir, E., Atmaca, M., Yildirim, Y., Bilgin, H. M., Demirtas, B., Obay, B. D., Kelle, M., Oflazoglu, H. D., Influence of coumarin and some coumarin derivatives on serum lipid profiles in carbontetrachloride-exposed rats. Hum. Exp. Toxicol. 2017, 36, 295-301.  Sashidhara, K. V., Kumar, A., Kumar, M., Srivastava, A., Puri, A., Synthesis and antihyperlipidemic activity of novel coumarin bisindole derivatives. Bioorg. Med. Chem. Lett. 2010, 20, 6504-6507.  Sashidhara, K. V., Palnati, G. R., Sonkar, R., Avula, S. R., Awasthi, C., Bhatia, G., Coumarin chalcone fibrates: a new structural class of lipid lowering agents. Eur. J. Med. Chem. 2013, 64, 422-431.  Axe, F. U., Bembenek, S. D., Szalma, S., Three-dimensional models of histamine H3 receptor antagonist complexes and their pharmacophore. J. Mol. Graph. Model. 2006, 24, 456-464.  Prathipati, P., Saxena, A. K., Characterization of b3-adrenergic receptor: determination of pharmacophore and 3D QSAR model for b3-adrenergic receptor agonism J. Comput. Aided. Mol. Des. 2005, 19, 93-110.  Kostova, I., Raleva, S., Genova, P., Argirova, R., Structure-activity relationships of synthetic coumarins HIV-1 inhibitors[J]. Bioinorganic chemistry and applications, 2006, 2006. Bioinorg. Chem. Appl. 2006, 9.  Cheng, J. F., Chen, M., Wallace, D., Tith, S., Arrhenius, T., Kashiwagi, H., Ono, Y., Ishikawa, A., Sato, Kozono, T., Sato, H., Nadzan, A. M., Discovery and structure-activity relationship of coumarin derivatives as TNF-α inhibitors. Bioorg. Med. Chem. Lett. 2004, 14, 2411-2415.  Niu, H. D., Wang, W. B., J.Y. Li, J., Lei, Y., Zhao, Y., Yang, W. X., Zhao, C. Y., Lin, B., Song, S. J., S. J., A novel structural class of coumarin-chalcone fibrates as PPAR alpha/gamma agonists with potent antioxidant activities: Design, synthesis, biological evaluation and molecular docking studies. Eur. J. Med. Chem. 2017, 138, 212-220. 37 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 38 Molecular Nutrition & Food Research  Shukla, P., Srivastava, S. P., Srivastava, R., Rawat, A. K., Srivastava, A. K., Pratap, R., Synthesis and antidyslipidemic activity of chalcone fibrates. Bioorg. Med. Chem. Lett. 2011, 21, 3475-3478.  Sancho, R., Marquez, N., Gomez-Gonzalo, M., Calzado, M. A., Bettoni, G., Coiras, M. T., Alcami, J., Lopez-Cabrera, M., Appendino, G., Munoz, E., Imperatorin inhibits HIV-1 replication through an Sp1-dependent pathway. J. Bio. Chem. 2004, 279, 37349-37359.  Zhou, P., Takaishi, Y., Duan, H., Chen, B., Honda, G., Itoh, M., Takeda, Y., Kodzhimatov, O. K., Lee, K. H., Coumarins and bicoumarin from Ferula sumbul: anti-HIV activity and inhibition of cytokine release. Phytochemistry 2000, 53, 689-697.  Shikishima, Y., Takaishi, Y., Honda, G., Ito, M., Takeda, Y., Kodzhimatov, O. K., Ashurmetov, O., Lee, H., Chemical Constituents of Prangos tschimganica; Structure Elucidation and Absolute Configuration of Coumarin and Furanocoumarin Derivatives with Anti-HIV Activity. Chem. Pharm. Bull. 2001, 49,  Zhang, Q. L., Zhao, J. H., Bi, J. J., Cao, J. R., Song, J., Wu, Z. Z., Three kinds of coumarins reverse the multidrug resistance activities of tumor cells in Fructus cnidii. Chin. Herb. Med. 2003, 12-14.  Zhou, Z. W., Liu, P. X., Reearch advances in chemical composition and antitumor activity of Fructus China. J. Chin. Mater. Med. 2005, 17, 1309-1313.  Zhou, J., Cheng, W. X., Xu, Y. H., Zhang, D. H., Wang, D. M., Experimental study on the inhibitory of osthol on lung adenocarcinoma and lung squamous carcinoma. Carcinogenesis Distortion Mutations 2002, 04, 231-233.  Wang, C. J., Hsieh, Y. J., Chu, C. Y., Lin, Y. L., Tseng, T. H., Inhibition of cell cycle progression in leukemia HL-60 cells by esculetin. Cancer. Lett. 2002, 183, 163-168.  Kok, S. H., Yeh, C. C., Chen, M. L., Kuo, M. Y. P., Esculetin enhances TRAIL-induced apoptosis through DR5 upregulation in human oral cancer SAS cells. Oral. Oncol. 2009, 45, 1067-1072.  Park, S. S., Park, S. K., Lim, J. H., Choi, Y. H., Kim, W. J., Moon, S. K., Esculetin inhibits cell through the Ras/ERK1/2 pathway in human colon cancer cells. Oncol. Rep. 2011, 25, 223. 38 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 39 Molecular Nutrition & Food Research  Liu, X., Zhang, L., Fu, X., Chen, K., Qian, B. C., Effect of scopoletin on PC3 cell proliferation and apoptosis. Acta Pharm Sin 2000, 22, 929-933.  Zhao, Y. Y., Cai, Y., Psoralen reverses the multidrug resistance activities of human breast cancer MCF-7 cell lines. J Tradit Chin Med 2006, 370-371.  Cai, Y., Yang, Y. X., Liang, S. L., Xu, Y., Effects of psoralen on the expression of Bcl-2 protein in multidrug resistant cell line of breast cancer. Chin. Herb. Med. 2004, 11, 855-856.  Zhang, R. H., He, S. G., The effects of quercetin, psoralen and isopsoralen on the p-glycoprotein and drug resistance in human breast cancer cells. J. Chin. Med. Univ. 2000, 04, 80-81.  Han, J. X., Wu, J. Z., Li, F., Chen, J. Y., Li, Y., The effects of 8-MOP on the expression of suppressor gene in MEC-1 Cells. J. Pract. Stomatol. 1999, 06, 457-458.  Pokharel, Y. R., Han, E. H., Kim, J. Y., Oh, S. J., Kim, S. K., E.R.Woo, Jeong, H. G., Kang, K. W., Potent protective effect of isoimperatorin against aflatoxin B1-inducible cytotoxicity in H4IIE cells: bifunctional effects on glutathione S-transferase and CYP1A. Carcinogenesis 2006, 27, 2483-2490.  Jiang, C., Lee, H. J., Li, G. X., Guo, J. M., Malewicz, B., Zhao, Y., Lee, E. O., Lee, H. J., Lee, J. H., Kim, S., Potent Antiandrogen and Androgen Receptor Activities of an Angelica gigas–Containing Herbal Formulation: Identification of Decursin as a Novel and Active Compound with Implications for Prevention and Treatment of Prostate Cancer. Cancer Res 2006, 66, 453-463.  Fong, W. F., Zhang, J. X., Wu, J. Y. C., Tse, K. W., Wang, C., Cheung, H. Y., Yang, M. S., (+/-)-4'-O-acetyl-3'-O-angeloyl-cis- khellactone induces mitochondrial-dependent apoptosis in HL-60 cells Planta. Med. 2004, 70, 489-495.  Jiang, Y. F., Shen, Q., Bai, B., Effects of capillarin on the proliferation and cell cycle of lung cancer cells. China. Pharm. 2002, 08, 30-31.  Wang, M., Chen, J. W., Li, X., In vitro antitumor activity of five furan coumarins in the root bark of Changium smyrnioides. Chin. J. Exp. Tradit. Med. Formu. 2012, 06, 203-205. 39 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 40 Molecular Nutrition & Food Research  Yu, F. H., Huang, X. Y., Effect of imperatorin on down-regulation of Mcl-1 protein expression in human hepatocellular carcinoma cell line HepG2. Zhejiang. J. Integ. Trad. Chin. West. Med. 2015, 04, 334-336+344.  Panno, M. L., Giordano, F., Palma, M. G., Bartella, V., Rago, V., Maggiolini, M., Sisci, D., Lanzino, M., Amicis, F. D., Ando, S., Evidence that bergapten, independently of its photoactivation, enhances p53 gene expression and induces apoptosis in human breast cancer cells. Curr. Cancer. Drug. Tar. 2009, 9, 469-481.  Finn, G. J., Creaven, B. S., Egan, D. A., Daphnetin induced differentiation of human renal carcinoma cells and its mediation by p38 mitogen-activated protein kinase. Biochem. Pharmacol. 2004, 67, 1779-1788.  Piao, X. L., Park, I. H., Baek, S. H., Kim, H. Y., Park, M. K., Park, J. H., Antioxidative activity of furanocoumarins isolated from Angelicae dahuricae. J Ethnopharmacol. 2004, 93, 243-246.  Aboul-Enein, H. Y., Kladna, A., Kruk, I., Lichszteld, K., Michalska, T., Effect of psoralens on Fenton-like reaction generating reactive oxygen species. Biopolymers 2003, 72, 59-68.  Buyukguzel, E., Hyrsl, P., Buyukguzel, K., Eicosanoids mediate hemolymph oxidative and antioxidative response in larvae of Galleria mellonella L. Comp. Biochem. Phys. A. 2010, 156, 176-183.  Lin, H. C., Tsai, S. H., Chen, C. S., Chang, Y. C., Lee, C. M., Lai, Z. Y., Lin, C. M., Structure-activity relationship of coumarin derivatives on xanthine oxidase-inhibiting and free radical-scavenging activities. Biochem. Pharmacol. 2008, 75, 1416-1425.  Wang, D. C., Zhang, X. Z., Feng, L., In vitro antioxidant activity of total coumarins in Peucedanum praeruptorum. Herald. Med. 2008, 08, 899-901.  Pei, Y., Ma, X. D., Yi, J., Li, S., Wang, S. Y., Ma, J., Effects of coumarins in Angelicae pubescentis on antioxidant function and glutamic acid content in Parkinson 's disease model rats. Chin. J. Gerontol. 2014, 05, 1272-1274.  Zheng, G. M., Li, Z. J., Liu, G. Y., Fu, Z., Zhang, X. C., Isolation of coumarins from Fructus Viticis Negundo and its antioxidation activity to lard. Fine. Chem. 2012, 04, 366-368+390. 40 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 41 Molecular Nutrition & Food Research  Lin, S., Liu, M. T., Wang, S. J., Li, S., Yang, Y. C., Shi, J. G., Coumarins and their antioxidant activities Fraxinus sieboldiana. China. J. Chin. Mater. Med. 2008, 14, 1708-1710.  Stavri, M., Gibbons, S., The antimycobacterial constituents of dill (Anethum graveolens). Phytother. Res. 2005, 19, 938-941.  Shen, S. G., A preliminary study on the mechanism of inhibitory effect of osthol on plant pathogenic Nanjing. Agr. Univ. 2004.  Liu, L. M., Wang, R. H., Chen, L., Yang, Q., Weng, X. G., Sun, J. H., Comparative study on antimicrobial activity of coumarin monomers of different original Cortex Fraxini. Chin J Informat Tradit Chin Med 2009, 39-42.  Yang, C. X., Wang, Y. J., Xie, M. J., Study on antimicrobial activity and mechanism of fraxetin. J. 2012, 703-705.  Xu, X. D., Hu, X. R., Yuan, J. Q., Yang, J. S., Studies on chemical constituents of coumarins from Sarcandra glabra. J Chin Mat Med, 900-902.  Sun, Y. F., Du, L. L., Zhou, L., Zhang, W. G., Miao, F., Yang, X. J., Geng, H. L., Study on antimicrobial active components of Viola philippica. J Chin Mat Med 2011, 2666-2671.  Tsai, W. J., Chen, Y. C., Wu, M. H., Lin, L. C., Chuang, K. A., Chang, S. C., Kuo, Y. C., Seselin from Plumbago zeylanica inhibits phytohemagglutinin (PHA)-stimulated cell proliferation in human peripheral blood mononuclear cells. J Ethnopharmacol. 2008, 119, 67-73.  Wang, D. C., Ma, J., Kong, Z. F., Liu, W. H., Experimental study onanti-inflammatory and analgesic of total coumarin of Peucedanum praeruptorum. Chin J Informat Tradit Chin Med 2004, 688-690.  Hu, R., Extraction and main pharmacodynamics of imperatorin from Radix Angelicae dahuricae. Univ. Chin. Med. 2010. 41 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 42 Molecular Nutrition & Food Research  Jeong, H. J., Na, H. J., Kim, S. J., Rim, H. K., Myung, N. Y., Moon, P. D., Han, N. R., Seo, J. U., Kang, H., Kim, J. J., Anti-inflammatory effect of Columbianetin on activated human mast cells. Bio. Pharm. Bull. 2009, 32, 1027-1031.  Moon, T. C., Jin, M., Son, J. K., Chang, H. W., The effects of isoimperatorin isolated from Agelicae dahuricae on cyclooxygenase-2 and 5-lipoxygenase in mouse bone marrow-derived mast cells. Arch. Pharm. Res. 2008, 31, 210-215.  Kang, K. H., Kong, C. S., Seo, Y., Kim, M. M., Kim, S. K., Anti-inflammatory effect of coumarins from Corydalis heterocarpa in HT-29 human colon carcinoma cells. Food. Chem. Toxicol. 2009, 47, 2129-2134.  Pan, R., Gao, X. H., Li, Y., Xia, Y. F., Dai, Y., Anti-arthritic effect of scopoletin, a coumarin compound occurring in Erycibe obtusifolia Benth stems, is associated with decreased angiogenesis in synovium. Fund. Clin. Pharmacol. 2010, 24, 477-490.  Wu, D. M., Li, Q. P., Rao, M. R., Effects of praeruptorin C on blood pressure and tail artery reactivity in renal hypertensive rats. Chin Pharmacol Bull 1997, 52-53.  Chang, T. H., Zhang, X. H., Xing, J., Wang, H. L., Liu, X. Y., Effects of praeruptorin A on the level of and the protein expression of Fas, bax and bcl-2 in myocardial ischemia reperfusion rats. J Chin Med Univ 2003, 5-7+10.  Dongmo, A. B., Azebaze, A. G. B., Nguelefack, T. B., Ouahouo, B. M., Sontia, B., Meyer, M., A. E., Kamanyi, A., Vierling, W., Vasodilator effect of the extracts and some coumarins from the stem of Mammea africana (Guttiferae). J Ethnopharmacol. 2007, 111, 329-334.  Zhou, L., Shangguan, Z., Lian, Q. S., Zhou, Q., Zeng, J., Xiang, R. D., Han, Y., Zhang, X. Y., study on antiarrhythmic effects of osthole. Chin. J. Mod. Appl. Pharm. 1996, 02, 11-13+70.  Lian, Q. S., Zhang, Z. Z., Shangguan, Z., Zhou, L., Pi, R. B., Xiang, R. D., Han, Y., Zhang, X. Y., Experimental study on antiarrhythmic effects of xanthotol. Chin. Herb. Med. 1996, 06, 347-349. 42 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 43 Molecular Nutrition & Food Research  Tang, C. K., Chen, G. J., The antihypertensive effect of oxypeucedanin. Chin. J. Mod. Appl. Pharm. 1994, 01, 14-16+58.  Li, D. J., Bai, Y. J., Zhang, S. Y., Wang, X. X., Effect of coumarins from Melilotus suaveolens Ledeb on blood pressure in rats. Brand 2014, 11, 260.  Rzodkiewicz, P., Gasinaka, E., Gajewski, M., Bujalska, Z., Szukiewicz, D., Maslinski, S., Esculetin leukotriene B4 level in plasma of rats with adjuvant-induced arthritis. Reumatologia 2016, 54, 161.  Kadakol, A., Pandey, A., Goru, S. K., Malek, V., Gaikwad, A. B., Insulin sensitizing and cardioprotective effects of Esculetin and Telmisartan combination by attenuating Ang II mediated vascular reactivity and cardiac fibrosis. Eur. J. Pharmacol. 2015, 765, 591-597.  Sanchez, R., Peinado, I. I., Molina-Jimenez, M. F., Benedi, J., Fraxetin prevents rotenone-induced by induction of endogenous glutathione in human neuroblastoma cells. Neurol. Res. 2005, 53, 48-56.  Kundu, J., Chae, I. G., Chun, K. S., Fraxetin Induces Heme Oxygenase-1 Expression by Activation of Akt/Nrf2 or AMP-activated Protein Kinase alpha/Nrf2 Pathway in HaCaT Cells. J. Caner. Prev. 2016, 21, 135-143.  Thuong, P. T., Pokharel, Y. R., Lee, M. Y., Kim, S. K., Bae, K., Su, N. D., Oh, W. K., Kang, K. W., Dual anti-oxidative effects of fraxetin isolated from Fraxinus rhinchophylla. Biol. Pharm. Bull. 2009, 32, 1527-1532.  Yamazaki, T., Tokiwa, T., Isofraxidin, a coumarin component from Acanthopanax senticosus, inhibits matrix metalloproteinase-7 expression and cell invasion of human hepatoma cells. Biol. Pharm. Bull. 2010, 33, 1716-1722.  Liu, L., Mu, Q. L., W, W. F. L., Xing, W., Zhang, H. L., Fan, T., Yao, H., He, L. C., Isofraxidin protects mice from LPS challenge by inhibiting pro-inflammatory cytokines and alleviating histopathological changes. Immunobiology 2015, 220, 406-413. 43 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 44 Molecular Nutrition & Food Research  Cuong, N. M., Khanh, P. N., Duc, H. V., Huong, T. T., Tai, B. H., Binh, N. Q., Durante, M., Fusi, F., Vasorelaxing activity of two coumarins from Murraya paniculata leaves. Biol. Pharm. Bull. 2014, 37, 694-697.  Tan, X. H., Tian, J. M., Zhao, J. L., Zhang, D. S., In vitro the antioxidant activity of osthol. Chin. Tradit. Med. 2013, 05, 1070-1072.  Li, X., Zeng, H. X., P, P. F. W., Lin, L., Liu, L., Zhen, P. Y., Fu, Y. Z., Lu, P. P., Zhu, H. Z., Reactivation latent HIV-1 in latently infected cells by coumarin compounds: Hymecromone and ScoparoneReactivation of Latent HIV-1 in Latently Infected Cells by Coumarin Compounds: Hymecromone and Scoparone. Curr. HIV. Res. 2016, 14, 484-490.  Kim, J. K., Kim, J. Y., Kim, H. J., Park, K. G., Harris, R. A., Cho, W. J., Lee, J. T., Lee, I. K., Scoparone exerts anti-tumor activity against DU145 prostate cancer cells via inhibition of STAT3 activity. PloS. One. 2013, 8, e80391.  Cho, D. Y., Ko, H. M., Kim, J., Kim, B. W., Yun, Y. S., Park, J. I., Ganesan, P., Lee, J. T., Choi, D. K., Scoparone Inhibits LPS-Simulated Inflammatory Response by Suppressing IRF3 and ERK in BV-2 Microglial Cells Molecules 2016, 21, 1718.  Park, S., Kim, J. K., Oh, C. J., Choi, S. H., Jeon, J. H., Lee, I. K., Scoparone interferes with proliferation of vascular smooth muscle cells. Exp. Mol. Med. 2015, 47, 1-8.  Zhu, M., Zhang, K. M., Ding, Y., Antioxidant activity evaluation of scopoletin and scoparone in capillaries. J. Shenyang. Pharm. Univ. 2016, 11, 889-893.  Pan, R., Dai, Y., Yang, J., Li, Y., Yao, X. J., Xia, Y. F., Anti-angiogenic potential of scopoletin is with the inhibition of ERK1/2 activation. Drug. Dev. Res. 2009, 70, 214-219.  Yu, S. M., Hu, D. H., Zhang, J. J., Umbelliferone exhibits anticancer activity via the induction of and cell cycle arrest in HepG2 hepatocellular carcinoma cells. Mol. Med. Rep. 2015, 12, 3869-3873. 44 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 45 Molecular Nutrition & Food Research  Sim, M. O., Lee, H. I., Ham, J. R., Seo, K. I., Kim, M. J., Lee, M. K., Anti-inflammatory and antioxidant effects of umbelliferone in chronic alcohol-fed rats. Nutr. Res. Pract. 2015, 9, 364-369.  Pan, L., Li, X. Z., Jin, H., Yang, X. Y., Qin, B., Antifungal activity of umbelliferone derivatives: and structure-activity relationships. Microb. Pathogenesis. 2017, 104, 110-115.  Zhou, Y., Wang, J., Yang, W. D., Qi, X. W., Lan, L., Luo, L., Yin, Z. M., Bergapten prevents lipopolysaccharide-induced inflammation in RAW264. 7 cells through suppressing JAK/STAT activation and ROS production and increases the survival rate of mice after LPS challenge. Int. Immunopharmacol. 2017, 48, 159-168.  Golfakhrabadi, F., Ardakani, M. R. S., Saeidnia, S., Akbarzadeh, T., Yousefbeyk, F., Jamalifar, H., Khanavi, M., In vitro antimicrobial and acetylcholinesterase inhibitory activities of coumarins from Ferulagocarduchorum. Med. Chem. Res. 2016, 25, 1623-1629.  Cao, Y. J., Zhang, Y. M., Wang, N., He, L. C., Antioxidant effect of imperatorin from Angelica dahurica hypertension via inhibiting NADPH oxidase activation and MAPK pathway. J. Am. Soc. Hypertens. 2014, 527-536.  Rahman, A., Na, M., Kang, S. C., Antilisterial potential of imperatorin and limonin from Poncirus Rafin. J. Food. Biochem. 2012, 36, 217-223.  Koziol, E., Skalicka-Wozniak, K., Imperatorin-pharmacological meaning and analytical clues: profound investigation. Phytochem. Rev. 2016, 15, 627-649.  Kang, T. J., Lee, S. Y., Singh, R. P., Agarwal, R., Yim, D. S., Anti-tumor activity of oxypeucedanin from Ostericum koreanum against human prostate carcinoma DU145 cells. Acta. Oncol. 2009, 48, 895-900.  Ngameni, B., Kuete, V., Simo, I. K., Mbaveng, A. T., Awoussong, P. K., Patnam, R., Roy, R., Ngadjui, B. T., Antibacterial and antifungal activities of the crude extract and compounds from Dorstenia turbinata (Moraceae). S. Afri. J. Bot. 2009, 75, 256-261. 45 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 46 Molecular Nutrition & Food Research  Marzaro, G., Guiotto, A., Borgatti, M., Finotti, A., Gambari, R., Breveglieri, G., Chilin, A., Psoralen derivatives as inhibitors of NF-kappa B/DNA interaction: synthesis, molecular modeling, 3D-QSAR, and biological evaluation. J. Med. Chem 2013, 56, 1830-1842.  Coimbra, S., Oliveira, H., Neuparth, M. J., Figueiredo, A., Rocha-Pereira, P., Santos-Silva, A., Inflammatory markers of cardiovascular disease risk in Portuguese psoriatic patients: relation with narrow-band ultraviolet B and psoralen plus ultraviolet A. Int. J. Dermatol. 2014, 53, 393-396.  Alexander, N. J., McCormick, S. P., Blackburn, J. A., Effects of xanthotoxin treatment on trichothecene production in Fusarium sporotrichioides. Can. J. Microbiol. 2008, 54, 1023-1031.  Lee, S. B., Lee, W. S., Shin, J. S., Jang, D. S., Lee, K. T., Xanthotoxin suppresses LPS-induced expression of iNOS, COX-2, TNF-alpha, and IL-6 via AP-1, NF-kappaB, and JAK-STAT inactivation in RAW 264.7 macrophages. Int. J. Immunopharmacol. 2017, 49, 21-29.  Liu, Z. J., Guo, X. Y., Liu, G., Modified calanolides incorporated with furan-2-nitro mimics against Mycobacterium tuberculosis. Bioorg. Med. Chem. Lett. 2015, 25, 1297-1300.  Lu, M., Nicoletti, M., Battinelli, L., Mazzanti, G., Isolation of praeruptorins A and B from Peucedanum praeruptorum Dunn. and their general pharmacological evaluation in comparison with extracts of the drug. Il. Farmaco. 2001, 56, 417-420.  Xiong, Y. Y., Wang, J. S., Wu, F. H., Li, J., Kong, L. Y., The effects of (+/-)-Praeruptorin A on airway inflammation, remodeling and transforming growth factor-beta 1/Smad signaling pathway in a murine of allergic asthma. Int. Immunopharmacol. 2012, 14, 392-400.  Yang, L., Li, X. B., Yang, Q., Zhang, K., Zhang, N., Guo, Y. Y., Feng, B., Zhao, M. G., Wu, Y. M., The neuroprotective effect of praeruptorin C against NMDA-induced apoptosis through down-regulating of GluN2B-containing NMDA receptors. Toxicol. In. Vitro. 2013, 27, 908-914.  Yoshikawa, M., Nishida, N., Ninomiya, K., Ohgushi, T., Kubo, M., Morikawa, T., Matsuda, H., Inhibitory effects of coumarin and acetylene constituents from the roots of Angelica furcijuga on 46 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 47 Molecular Nutrition & Food Research D-galactosamine/lipopolysaccharide-induced liver injury in mice and on nitric oxide production in lipopolysaccharide-activated mouse peritoneal macrophages. Bioorg. Med. Chem. 2006, 14, 456-463.  Bedoya, L. M., Beltran, M., Sancho, R., Olmedo, D. A., Sanchez-Palomino, S., Olmo, E., Lopez-Perez, J. L., Munoz, E., San, A., Alcami, J., 4-Phenylcoumarins as HIV transcription inhibitors. Bioorg. Med. Chem. Lett. 2005, 15, 4447-4450.  Suparji, N. S., Chan, G., Sapili, H., Arshad, N. M., In, L. L. A., Awang, K., Nagoor, N. H., Geranylated 4-Phenylcoumarins Exhibit Anticancer Effects against Human Prostate Cancer Cells through Caspase-Independent Mechanism. PloS. One. 2016, 11, e0151472.  Sun, J., Ding, W. X., Zhang, K. Y., Zou, Y., Efficient synthesis and biological evaluation of derivatives. Chin. Chem. Lett. 2011, 22, 667-670.  Taechowisan, T., Lu, C., Shen, Y., Lumyong, S., In vitro anti-inflammatory activity of 4-arylcoumarins from endophytic Streptomyces aureofaciens CMUAc130 in murine macrophage RAW 264.7 cells. Nat. Prod. Res. 2007, 21, 1104-1113.  Meepagala, K. M., Sturtz, G., Wedge, D. E., Antifungal constituents of the essential oil fraction of dracunculus L. var. dracunculus. J. Agric. Food. Chem. 2002, 50, 6989-6992. 47 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 48 Figure 1. Molecular Nutrition & Food Research Structures of simple and other coumarins. 48 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 2. Page 49 Molecular Nutrition & Food Research Structures of linear furanocoumarins. (3-7, 59, 78-81, 84) 49 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 3. Figure 4. Page 50 Molecular Nutrition & Food Research Structures of angular furanocoumarins. (22, 55-58, 89) Structures of angular pyranocoumarins(47-48, 88) and linear pyranocoumarins(53-54). 50 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 5. Page 51 Molecular Nutrition & Food Research Structures of tetracyclic pyrancoumarins. (1-2, 13-16) 51 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 6. Page 52 Molecular Nutrition & Food Research Structures of khellactone derivatives. (17-19, 26-28, 49-52, 72-73) Figure 7. Structures of bicoumarins (34-38, 87, 90) 52 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 8. Page 53 Molecular Nutrition & Food Research Structures(8-12) and their IC50 values for quantitative structure–activity relationship analysis Figure 9. Key structural components of isoprenylated coumarins 53 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 10. Page 54 Molecular Nutrition & Food Research Synthesis of compounds 29-32 and their IC50 values as inhibitors against CNE2, Cal27 and KB cell lines. Figure 11. Synthesis of compounds 39-44 54 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 12. Figure 13. Page 55 Molecular Nutrition & Food Research Synthesis of compounds 65-66. Reagents and conditions: (d) Br2 in CH3COOH; (e) C2H5OH, Reflux, 5 h. Structures(67-71) and their IC50 values as inhibitors of NO and PGE2 productions in LPS-induced RAW 264.7 macrophages. 55 This article is protected by copyright. All rights reserved. www.mnf-journal.com Figure 14. Page 56 Molecular Nutrition & Food Research The pharmacological effects and structure-activity relationships mechanisms mentioned in this article 56 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 57 Molecular Nutrition & Food Research Graphic Abstract Coumarins are naturally occurring, versatile synthetic compounds with potential anti-HIV, anticancer, antioxidant, antimicrobial, anti-inflammatory analgesic, and anti-cardiovascular disease activities. This review compiles information from publications on the coumarin and its derivatives and proposes structure-activity relations and the structural modification to open up an important way for the further rational application of coumarins and the development of related new drugs. 57 This article is protected by copyright. All rights reserved. www.mnf-journal.com Table 1. Page 58 Molecular Nutrition & Food Research The coumarins with anti-HIV activities and their mechanisms determined on the EC50 of inhibiting the formation of syncytia, taking TI as the testing index Active Ingredients Source Result Mechanism References Imperatorin(59) Radix Angelicae dahuricae Inhibit the HIV-1 virus replication Strongly inhibit the cyclin D1 expression and arrest the cells at the G1 phase of the cell cycle  Calanolide A(1), Calophyllum inophyllum Good selectivity, have strong inhibitory effects on HIV-1 virus, but invalid for HIV-2 virus Calanolide A (1)  is homologous to the HIV-1 RT and the DNA polymerase in the alpha binding site. Angelica apaensis Oxypeucedanin (3) has the best anti-HIV activity, TI is 17.59. TI of the other coumarin monomers is small, less than 5 Inhibit the HIV replication, mainly acting on HIV RT, HIV PR and HIV IN  Imperatorin(59) Ferula sumbul 27 kinds of coumarins are isolated from the methanol extract, in which the imperatorin (59) TI is 1000 with the best activity Inhibit the HIV replication  Suksdorfin(18) Lomatium suksdorfii TI>40 Significantly inhibit the HIV replication in H9 lymphocytes  calanolide B(2) Oxypeucedanin(3) oxypeucedanin hydrate(4) isoimperatorin(5) 58 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 59 Prangos tschimganica Psoralen(78) bergapten(79) Table 2. TI respectively is 191, 11.7. Molecular Nutrition & Food Research Inhibit the replication of HIV-1 in H9 lymphocytes  The coumarins with anti-tumor activities and their mechanisms Active Ingredients Source Experimen tal Model and Method Result Mechanis m Refere nces Imperatori n(59) Fructus cnidii KBV200 cells/ Vincristine (VCR) The reversal factor for VCR was 8.27 Reverse tumor cells  Hela-S3 cells Inhibit the proliferation of cancer cells as the content is greater than 5μg/mL. The inhibition intensity order is osthole(23)>xanthotol(80)>bergapten( 79)>xanthotoxin(81) Inhibit the Hela cell proliferati on  Human lung adenocarci noma and squamous carcinoma in mice The inhibitory rate of lung adenocarcinoma was 50.0%; the inhibitory rate of squamous carcinoma was 69.5% Have a certain inhibitory effect on the invasion of cancer tissue  HL-60 cells in G1 phase The proliferation of HL-60 is slowed down Induce the G1 phase cell cycle  Osthole(23 ) xanthotol(8 0) bergapten( 79) xanthotoxi n(81) Osthole(23 ) Esculetin(3 3) Cortex Fraxini 59 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 60 Molecular Nutrition & Food Research arrest Human oral cancer SAS cells 10μg/mL of esculetin reduce the number of SAS cells by 30% after 48h of incubation and a 60% decrease in cell number for 72 h of treatment Enhance TRAIL-ind uced apoptosis primarily through upregulat ion of DR5  Human colon cancer cells Result in significant growth inhibition and G1 phase cell cycle arrest Block the Ras/ERK1 /2 signaling pathway and decrease G1 phase cell cycle protein levels   Scopoletin( 60) Porana racemos a PC3 cells, PAa cells, Hela cells IC50 are 157, 154 and 294μg/mL, the inhibition of PC3 cells proliferation is time-dependent and concentration-dependent, the G2 phase cells are significantly decreased Decrease intracellul ar protein content and reduce acid phosphat ase activity Psoralen (78) Fructus psoralea e MCF-7/ ADR Decrease the IC50 of MCF-7/ ADR cells to ADR, increase the intracellular ADR concentration Reverse  the MDR to improve the effect of chemothe 60 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 61 Molecular Nutrition & Food Research rapy Xanthotoxi n (81) Radix Angelica e dahurica e K562/ADR Significantly reduce the IC50 of ADR to K562 after combined 3h Have a  reversal effect on MDR resistance EMT6 cells Show significant growth inhibition of EMT6 at the dose concentration of 2.23μg/mL both in vivo and in vitro May be related to the relative reduction of cell DNA content, cell mitochon drial degenera tion and cell vacuolati on MEC-1 cells MEC-1 cells are dose-dependent inhibited when the dose is greater than 25μg/mL Act on  the cell cycle regulatio n mechanis m associate d with the G1/S conversio n restrictio n point to inhibit cell proliferati 61 This article is protected by copyright. All rights reserved.  www.mnf-journal.com Page 62 Molecular Nutrition & Food Research on Isoimperat orin(5) Fructus aurantii Aflatoxin B1(AFB1) Significantly inhibit the cytotoxic effect of AFB1 when the dose is greater than 0.3μM Enhance  the activity of glutathio ne S-transfer ase to inhibit the cytochro me P-448, thereby inhibit the toxicity of AFB1, reduce the incidence of liver cancer Decursin(5 3) Koren Angelica gigas Nakai LNCaP cells IC50 is similar to 7μg/mL after 48 hours exposure Selectivel y induce LNCaP cells division to stop at G1 phase, inducing apoptosis  Praeruptori n C(73) Peuceda num praerupt orum HL-60 cells Can promote HL-60 cells apoptosis in the 10~30μg/mL and the degree of apoptosis increase Cause apoptotic DNA and nuclear fragment ations in HL-60 cells  62 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 63 Molecular Nutrition & Food Research Capillarin(8 2) Artemisi a capillarie s PAa cells The inhibitory rate are most obvious, reaching 52.4% ,at the dose of 0.16μg/mL Inhibit the DNA synthesis, block the cells in the G0/G1 phase, thereby inhibit the proliferati on of PAa cells  Imperatori n(59) Changiu m smyrnioi des Hep-G2 The anti-tumor effect of isoimperatorin(5) is the best, IC50 is 0.39~4.11μg/mL Induce the apoptosis of Hep-G2 ,[ 127] Bergapten( 79) Angelica e pubesce ntis Human breast cancer cell lines MCF-7 and SKBR 3 Induce the block in the G0/G1 phase Increase the mRNA and protein levels of p53 and p21waf  Daphnetin( 83) Daphne Korean Nakai Hep-G2 cells Low dose inhibits the cell cycle to stagnate in the S phase, high dose is to stagnate in the late G1 and S early Inhibit the activity of PKA and PKC, and up-regula te the activity of p38MAPK  Isoimperat orin(5) Tabla 3. The coumarins with antioxidant activities and their mechanisms 63 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 64 Molecular Nutrition & Food Research Active Ingredients Source Experimental Model and Method Result Mechanis m Referenc es Alloisoimperatorin( 84) Angelicae dahuricae DPPH/AAPH /Renal epithelial cells Inhibit the damage of DPPH-induced and AAPH-induced renal epithelial cells Generate peroxyl radicals in vitro  Psoralen (78) Fructus psoraleae Fenton-Like Reaction Can improve the ROS in vivo at the 1 mM dose High dose of psoralen(7 8) may have an oxidative effect in vivo  Xanthotoxin (81) Radix Angelicae dahuricae First-instar larvae of Galleria mellonella SOD, GST and GPX in blood increase, catalase activity decrease Mediate the eicosanoid s antioxidant enzymes  Esculetin(33) Cortex Fraxini ROS the most potent radical scavenger among the eight tested compounds Protect cells against ROSmediated protein damage  Semen Euphorbiae Lathyridis DPPH The final concentration of clearing the DPPH (IC50=0.058μg/mL )is far below the final concentration of VC system With o-phenolic hydroxyl structure, easy to combine with free  64 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 65 Molecular Nutrition & Food Research (IC50=0.542μg/mL ) radicals Praeruptorin C(73) Peucedanu m praeruptoru m Mice Remove the •OH and O2－•, inhibit the MDA production in mouse liver homogenate Its anti-lipid peroxidatio n may be related to the scavenging free radical effect  Coumarins from Angelicae Pubescentis Angelicae Pubescentis Parkinsonian disease(PD) rat models Significantly reduce the content of MDA and Glu in serum and brain tissue of PD rats, increase the activity of T-SOD in serum Inhibit the lipid peroxidatio n in serum and brain tissue, improve antioxidant enzyme activity  Isofraxidin(85) Negundo Chastetree Fruit Lard The antioxidant effect is w (BHT)=0.02% when the addition amount is 0.04% in lard Ortho phenolic hydroxyl has electron donor groups, forming a stable free radicals after hydrogen generation ; polarity is not large with better solubility  65 This article is protected by copyright. All rights reserved. www.mnf-journal.com Fraxetin(86) Page 66 Fraxinus sieboldiana Table 4. Fe2+-cysteine/r at liver microsomes lipid peroxidation model Molecular Nutrition & Food Research The inhibition of the lipid peroxidation product MDA is more than 50% at 10-6 mol L-1 concentration Unkown  The coumarins with antimicrobial activities and their mechanisms Active Ingredients Source Experiment al Model and Method Result Mechanism Refere nces Oxypeucedanin(3) Anethu m graveol ens Mycobacte ria The MIC values in the range 2-128μg/mL The antimycoba cterial activity of the substances is dependent on the position and polarity of the geranyl moiety  Fructus cnidii Fusarium graminear um EC50=56.94μg/mL . When the concentration is more than 25μg/mL, the dry weight of mycelial growth is inhibited, the spore germination is significantly May be through the inhibition of the calcium absorption, affect the transport of vesicle to the mycelium top, the  oxypeucedanin hydrate(4) Osthole(23) 66 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 67 Molecular Nutrition & Food Research inhibited spore germination is blocked Fraxetin(86),esculetin(33) Cortex Fraxini Staphyloco The order of ccus aureus antibacterial activity is fraxetin(86)>escul etin(33) Fraxetin(86) can inhibit the synthesis of nucleic acid and soluble proteins in the cells. ,[1 41] 4,4′-biisofraxidin (87), Sarcan dra glabra Porphyrom onas gingivalis, Streptococ cus mutans The antibacterial effect of isofraxidin(85) on Porphyromonas gingivalis is the best, MIC=78μg/mL; the antibacterial effect of 4,4'-biisofraxidin( 87) on Streptococcus mutans is the best, MIC=125μg/mL unkown  Viola philippi ca Escherichia coli (E.coli), The activity of esculetin(33) is the best, and the MIC=31~313μg/m L, MBC=313~625μg/ mL 7-hydroxyl is  the main active group against E.coli, Salmonella and S.agalactiae , 6-hydroxyl is the main active group against S.dysgalacti esculetin(33), fraxetin(86), scoparone(74), isofraxidin(85) Esculetin(33),scoparone(74),s copoletin(60) Streptococ cus agalactiae (S.agalacti ae), Streptococ cus dysgalactia e (S.dysgalac 67 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 68 Molecular Nutrition & Food Research tiae), Salmonella Table 5. a The coumarins with anti-inflammatory analgesic activities and their mechanisms Active Ingredients Sourc e Experime ntal Model and Method Result Mechan ism Seselin(88) Plumb ago zeylan ica Phytolecti n(PHA)/ human periphera l blood mononucl ear cells(PBM C) That PHA stimulates the proliferation of PBMC is inhibited, IC50=(53.87± 0.74) μM Inhibit  the PBMC prolifera tion by inhibitin g inflamm atory cytokine s IL-2 and IFN-γ Total coumarins from Peucedanum praeruptorum Dunn Peuce Rats danu m praeru ptoru m Significantly inhibit the rats toe-swell by egg albumen; 3h is the strongest inhibitory effect after inflammation, sustained more than 6h unkown  Imperatorin(59) Radix Angeli Reduce the amount of Inhibit the  68 This article is protected by copyright. All rights reserved. Carragee nan-induc Refe renc es www.mnf-journal.com Page 69 Molecular Nutrition & Food Research cae dahuri cae ed acute pleurisy in rats pleural effusion, decrease the number of white blood cells and neutrophils, increase the number of lymphocytes release of TNF-α, PGE2 in inflamm atory tissue Columbianetin(58) Angeli ca biserr ata Human mast cells(HMC -1) Regulate allergic inflammatory responses mutagenized of the the HMC-1 Significa ntly inhibit the expressi on of TNF-α and COX-2; regulate d by substan ce P, activate (or inhibit) the release of histami ne  Isoimperatorin(5) Angeli cae dahuri cae Bone marrow-d erived mast cells (BMMC) IC50=10. 7mM Inhibit the producti on of COX-1 that is COX-2-d epende nt and  69 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 70 Molecular Nutrition & Food Research PGD2-d epende nt Libanoridin (89) Coryd alis yanhu suo Lipopolys accharide stimulate d HT-29 cells Inhibit the transcriptiona l activity of lipopolysacch aride-stimulat ed nuclear factor Inhibit the expressi on of protein in inflamm atory mediato rs such as NOS, COX-2, TNF-α, IL-1β Osthole(23),phebalosin(61),meranzin(62),u mbelliferone(63),scopoletin(60),murracarpi n(64) Murra ya panicu lata Kunming mice with writhing analgesia and xylene-in duced ear swelling mice model Murracarpin( 64) has the strongest anti-inflamma tory and analgesic activity May be  related to its C-7 methox yl group, C-8 short chain containi ng double bonds and alcohol hydroxyl Daphnoretin(90), umbelliferone(63) Daphn e tangu tica Maxi Rat toe swelling test and rat primary Umbelliferon e(63) with analgesic activity, daphnoretin( 7,8-disu bstitute d coumari ns are 70 This article is protected by copyright. All rights reserved.   www.mnf-journal.com Page 71 Scopoletin(60) Table 6. Molecular Nutrition & Food Research m arthritis model 90) with anti-inflamma tory analgesic activity of anti-infl ammato ry and analgesi c activitie s Erycib e obtusi folia Benth Rat adjuvant-i nduced arthritis Reduce the numbers of new blood vessels in the synovium and the production of important endogenous angiogenic inducers Down regulate the over expressi on of vascular endothe lial growth factor, basic fibrobla st growth factor and IL-6  The coumarins with anti-cardiovascular disease activities and their mechanisms Active Ingredients Source Experimen tal Model and Method Result Mechanism Referenc es Praeruptorin C (73) Peucedanu m praeruptor um Renal hypertensi ve rats Significantly lower blood pressure, reduce the norepinephrine-indu ced and KCl-induced contraction Inhibit the voltage-depende nt calcium channels and receptor-induced calcium channels,  71 This article is protected by copyright. All rights reserved. www.mnf-journal.com Page 72 Molecular Nutrition & Food Research reactivity in rat tail artery decrease the intracellular Ca2+ content Praeruptorin A (26) Peucedanu m praeruptor um Male Wistar rats Reduce the levels of IL-6 Block the calcium influx, open the potassium channels, alleviate ischemia-reperfus ion caused cytoplasmic Ca2+ overload, maintain intracellular calcium balance and mitochondrial stability  4-phenylcoumar ins Mammea africana Rat aorta Relaxation of blood vessels Interfered with the liberation of Ca2+ into the muscle cell  Osthole (23), xanthotol (80) Fructus cnidii White rabbits, toads Significantly improve the threshold of ventricular fibrillation current of rabbit, reduce action potential amplitude of the sciatic nerve in toads Block the sodium ,[15 channels and 5] calcium channels of cardiomyocyte membrane, inhibit the sodium current and calcium current, hinder the myocardial cell depolarization Oxypeucedanin (3) Radix Angelicae dahuricae Adult sprague dawley rats Have a slow, dose-dependent hypotensive effect of the anesthetized rats, conscious normal blood May be related to the relaxation of vascular smooth muscle 72 This article is protected by copyright. All rights reserved.  www.mnf-journal.com Page 73 Molecular Nutrition & Food Research pressure rats and conscious kidney hypertensive rats Total coumarins from Melilotus suaveolens Ledeb. Melilotus suaveolens Ledeb. Table 7. Have a significant antihypertensive effect on the symptoms of hypertension Rats unkown  The summary of pharmacological activities of main coumarins in this article Coumarin monomers Anti-HI V Anti-tum or Antioxida nt Antimicrob ial activity Anti-inflammat ory analgesic Anti-cardiovasc ular disease Esculetin (33) + + + + + + Fraxetin (86) – + + + + + Isofraxidin (85) – + + + + – Meranzin (62) – + – – + – Murracarpin (64) – – – – + + Osthole (23) – + + + + + Scoparone (74) + + + + + + Scopoletin (60) – + + + + + Umbelliferone (63) – + + + + – Bergapten (79) – + + + + – Imperatorin (59) + + + + Isoimperatorin (5) + + + + 73 This article is protected by copyright. All rights reserved. ＋ + + – www.mnf-journal.com Page 74 Molecular Nutrition & Food Research Oxypeucedanin (3) + + – + – + Psoralen (78) + + + + + + Xanthotoxin (81) – + + + + – Calanolide B (2) + – – + – – Praeruptorin A (26) – + + + + + Praeruptorin C (73) – + + – – + Suksdorfin (18) ＋ – – – + + 4-phenylcouma rins + + + + + + Capillarin (82) － ＋ － + – – Calanolide A (1)/ This table is used to list what kinds of pharmacological effects coumarin monomers correspondingly have, "+" means yes, "-" means no or unknown. 74 This article is protected by copyright. All rights reserved.