Supplementary Information
Russulfoen, a new cytotoxic marasmane sesquiterpene from Russula
foetens
Ki Hyun Kim1, Hyung Jun Noh1, Sang Un Choi2, Ki Moon Park3, Soon-Ja Seok4 and
Kang Ro Lee1
1
Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, Suwon 440-
746, Korea
2
Bio-organic Science Division, Pharmacology Research Center, Korea Research Institute of
Chemical Technology, Teajeon 305-600, Korea
3
Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon 440-746,
Korea
4
Division of Applied Microbiology, RDA, National Institute of Agricultural Science and
Technology, Suwon 441-707, Korea
General
Optical rotations were measured on a Jasco P-1020 polarimeter (Jasco, Easton, MD, USA).
IR spectra were recorded on a Bruker IFS-66/S FT-IR spectrometer (Bruker, Karlsruhe,
Germany).
UV spectra
were
recorded
with
a
Shimadzu
UV-1601
UV-Visible
spectrophotometer (Shimadzu, Tokyo, Japan). Fast-atom bombardment (FAB) and HR-FAB
mass spectra were obtained on a JEOL JMS700 mass spectrometer (JEOL, Peabody, MA,
USA). Nuclear magnetic resonance (NMR) spectra, including 1H-1H COSY, heteronuclear
single quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC)
experiments, were recorded on a Varian UNITY INOVA 500 NMR spectrometer (Varian,
Palo Alto, CA, USA) operating at 500 MHz (1H) and 125 MHz (13C), with chemical shifts
given in ppm (δ). Preparative high performance liquid chromatography (HPLC) used a Gilson
306 pump (Gilson, Middleton, WI, USA) with a Shodex refractive index detector (Shodex,
New York, NY, USA). The packing material for molecular sieve column chromatography was
Sephadex LH-20 (Pharmacia, Uppsala, Sweden). Merck precoated Silica gel F254 plates and
RP-18 F254s plates (Merck, Darmstadt, Germany) were used for TLC. Spots were detected on
TLC under UV light or by heating after spraying with 10% H2SO4 in C2H5OH (v/v).
Mushroom Material
The fresh fruiting bodies of R. foetens were collected at Mt. Odea, Pyeongchang of Gangwon
province, Korea, in September, 2005. A voucher specimen (SKKU-2005-9) of the mushroom
was authenticated by one of the authors (S.J.S.) and was deposited at the School of Pharmacy
in Sungkyunkwan University, Korea.
Physico-chemical properties
Russulfoen (1). colorless oil, [α]25
D +29.3 (c 0.15, CHCl3), UV λmax (MeOH) nm (log ε) 217
(2.8), 252 (2.0), IR (KBr) 3388, 2946, 2836, 1751, 1456, 1028, 799 cm-1. 1H- and 13C-NMR
spectra: see Table 1. FAB-MS m/z 267 [M + H]+. HR-FAB-MS (positive-ion mode) m/z
267.1590 ([M + H]+, C15H23O4, calcd. for 267.1596).
Preparation of the (R)- and (S)-MTPA ester derivatives of 1
Compound 1 (1.3 mg) in deuterated pyridine (0.75 mL) was transferred into a clean NMR
tube. (S)-(+)-α-Methoxy-α-(trifluoromethyl)phenylacetyl (MTPA) chloride (10 μL) was
added into the NMR tube immediately under a N2 gas stream, and then the NMR tube was
shaken carefully to mix the sample and MTPA chloride evenly. The NMR reaction tube was
left at room temperature overnight. The reaction was then completed to afford the bis[(R)MTPA] ester derivative (1r) of 1. The bis[(S)-MTPA] ester derivative of 1 (1s) was obtained
as described for 1r. The 1H NMR spectra of 1r and 1s were measured directly in the NMR
reaction tubes.
1s. 1H NMR (500 MHz, pyridine-d5) δ 7.999 (2H, m, MTPA-ArH), 7.581 (2H, m, MTPAArH), 7.451-7.397 (6H, m, MTPA-ArH), 6.257 (1H, dd, J = 11.0, 8.0 Hz, H-8), 4.825 (1H, d,
J = 12.0 Hz, H-14a), 4.796 (1H, t, J = 10.0 Hz, H-13a), 4.706 (1H, d, J = 12.0 Hz, H-14b),
4.413 (1H, dd, J = 10.0, 7.0 Hz, H-13b), 3.832 (3H, s, OCH3), 3.561 (3H, s, OCH3), 2.574
(1H, m, H-2), 2.253 (1H, m, H-7), 1.901 (1H, m, H-9), 1.663 (1H, dd, J = 14.0, 6.0 Hz, H-1a),
1.611 (1H, dd, J = 14.0, 2.0 Hz, H-10a), 1.506 (1H, dd, J = 14.0, 7.0 Hz, H-10b), 1.383 (1H,
dd, J = 14.0, 12.0 Hz, H-1b), 1.382 (3H, s, H-12), 1.284 (1H, d, J = 4.0 Hz, H-4a), 1.283 (3H,
s, H-15), 0.952 (1H, d, J = 4.0 Hz, H-4b).
1r: 1H NMR (500 MHz, pyridine-d5) δ 7.998 (2H, m, MTPA-ArH), 7.581 (2H, m, MTPAArH), 7.450-7.396 (6H, m, MTPA-ArH), 6.233 (1H, dd, J = 11.0, 8.0 Hz, H-8), 4.832 (1H, d,
J = 12.0 Hz, H-14a), 4.785 (1H, t, J = 10.0 Hz, H-13a), 4.709 (1H, d, J = 12.0 Hz, H-14b),
4.410 (1H, dd, J = 10.0, 7.0 Hz, H-13b), 3.833 (3H, s, OCH3), 3.561 (3H, s, OCH3), 2.577
(1H, m, H-2), 2.240 (1H, m, H-7), 1.909 (1H, m, H-9), 1.664 (1H, dd, J = 14.0, 6.0 Hz, H-1a),
1.613 (1H, dd, J = 14.0, 2.0 Hz, H-10a), 1.520 (1H, dd, J = 14.0, 7.0 Hz, H-10b), 1.387 (1H,
dd, J = 14.0, 12.0 Hz, H-1b), 1.381 (3H, s, H-12), 1.279 (1H, d, J = 4.0 Hz, H-4a), 1.288 (3H,
s, H-15), 0.950 (1H, d, J = 4.0 Hz, H-4b).
Test for cytotoxicity in vitro.
A sulforhodamin B bioassay (SRB) was used to determine the cytotoxicity of each compound
against four cultured human cancer cell lines.13 The assays were performed at the Korea
Research Institute of Chemical Technology. The cell lines used were A549 (non small cell
lungcarcinoma), SK-OV-3 (ovary malignant ascites), SK-MEL-2 (skin melanoma), and HCT15 (colon adenocarcinoma). Doxorubicin was used as the positive control. The cytotoxicities
of doxorubicin against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines were at IC50
values of 0.021, 0.003, 0.012, and 0.038 μM, respectively.