Vitamins №8
Vitamins of the heterocyclic row:
pyrimidinetiazol, isoalloxazine,
corrine. Properties, quality
requirements, storage, application.
Multivitamin drugs.
prepared as. Medvid I.I.,
as.Kozachok S.S.
Heterocyclic row vitamins
Chromane derivatives
Heterocyclic vitamins, chromane derivatives (vitamins
of Е group - tocopherols), are in (Corn, cotton, flax,
peanuts, sea buckthorn, etc.) oils, and in the green
parts of plants, especially in the young shoots of
cereals. They are also available in small quantities in
milk, butter, egg yolks, meat, fats.
Source of tocopherols extraction is wheat germ oil, or
corn.
In industry, the vitamin E extracted from natural
sources or by synthesis.
The basis of the structure of E vitamin group is
a tocol molecule - 6-oxy-2-methyl-2 (4 ', 8', 12'trimethyltridecyl) chromane:
Different tocopherols by the number of methyl
groups in the core of chromane, there are
seven natural vitamins of E group. The most
active-α-tocopherol. In clinical practice using
tocopherol acetate.
Obtaining of α-tocopherol
Tocopherol acetate is synthetically extracted by the
condensation of trimethylhydroquiinone with
phythilbromide and subsequent acetylation of αtocopherol:
Phythilbromide is extracted from phytol
containing in the nettles. From 1 ton of nettles get
about 3 kg of phytol.
Tocopherol acetate
(Tocopheroli acetas) Vitamin Е
(±)-2,5,7,8-tetramethyl-2-(4',8',12'-trimethyltridecyl)-6acetoxichromane
CHARACTERS. Light yellow, transparent, thick, oily liquid
with low odor. Practically insoluble in water, soluble in 95%
alcohol and very easily soluble in ether, acetone, chloroform,
and oils. Under the influence of light tocopherol acetate is
oxidized and darkened.
Identification of Tocopherol acetate
1.
Oxidation of the fuming nitric acid, at the heating in a water bathe –
appearance a red-orange color (o-tocopherylquinone).
If we continue the condensation of o-tocopherylquinone with ophenylenediamine, then forming a phenazine dye of red-orange
color with a yellow-green fluorescence
2. Tocopherol acetate is hydrolyzed by a solution of
potassium hydroxide in absolute alcohol (at the
heating), then to add the concentrated sulfuric acid –
feeling the smell of ethyl acetate.
3. At the oxidation of tocopherol by a potassium
ferricyanide in an alkaline medium there is formed
colored di-α-tocopherol:
Assay
1.
2.
3.
4.
Cerimetry. Direct titration after hydrolysis, indicator –
diphenilamine. Е = ½ М.m.
Firstly tocopherol is hydrolyzed by boiling with
H2SO4, and then extracted tocopherol is titrated with
cerium (IV) sulfate to the blue-violet color.
Photocolorimetry
Liquid chromatography
Spectrophotometry.
Storage
Store protected from light in a cold place.
Application
An important antioxidant. It participates in the
biosynthesis of proteins and other important metabolic
processes in cells. At its insufficient amount appearance
the degenerative changes in nerve cells, skeletal
muscle, cardiac muscle, increased fragility and
permeability
of
capillaries.
Apply for nervous diseases, muscular dystrophy,
sclerosis, menstrual irregularities and the threat of
termination of pregnancy, dysfunction of the sexual
men glands, to improve vision, with radiation sickness,
etc.
Using 50-100 mg / day (sometimes up to 400 mg) as
oil solutions of 5%, 10%, 30% α-tocopherol;
intra/muscular - 5%, 10%, 30% oil solutions; inside Capsules 100 , 200, 400 mg.
Heterocyclic vitamins
Phenylchromane derivatives (flavan)
Flavans derivatives are naturally in a free state, or in
conjunction with sugars (glycosides) - flavonoids.
Flavonoids are a group of Vitamins P. They are able
to reduce the fragility and permeability of
capillaries, take part in the ox-red processes and
have specific antioxidant properties.
They are in green tea, rose hips, citrus fruit, unripe
walnuts, mountain ash.
How drugs they are used as - quercetin, rutin, and
their natural (katergen) and semisynthetic
(troxevasin) analogues.
Rutin (Rutinum)
3-Rutinoside quercetin or 3-ramnoglycosyl-3,5,7,3',4'-pentaoxiflavone
Belongs to a glycosides class: quercetin aglycone is 3,5,7,3 ',
4'-pentaoxiflavon; sugar molecule part - rutenoza is a
disaccharide consisting of D-glucose and L-rhamnose.
Rutin is found in the leaves and fragrant flowers of rue (Ruta
graveolens), buckwheat (Fagopyrum esculentum).
CHARACTERS
Greenish-yellow finely crystalline powder,
odorless and tasteless. Practically insoluble in water,
slightly soluble in alcohol, it is difficult to dissolve in
boiling alcohol, practically insoluble in acid solution,
ether, chloroform, acetone and benzene, soluble in
dilute alkali.
Identification
1. The reaction wth iron (III) chloride - there is a dark
green color (the presence of phenolic groups).
2. Mineral acids at the heating hydrolyze rutin with the
formation of quercetin, glucose and rhamnose.
Quercetin + H2SO4 → oxonium salt is bright yellow
color with a green fluorescence.
3. Glucose residue is detected after acidic hydrolysis by
the reaction with copper-tartrate reagent (Feling).
4.
When dissolved a substance in a sodium hydroxide
solution appears yellow-orange color. According to
the reaction flavonoid becomes into halcon:
The presence of two absorption maxima in the UV
spectrum at 259 and 362.5 nm.
6. Reactions on the keto group (formation of oxime,
phenylhydrazone, semicarbazone).
5.
7.
Rutin is reduced by hydrogen in an acidic medium,
and forming the perylene salts, which have red
colors (cyanine reaction). For occurring of this
reaction to the alcohol solution of substance to add
concentrated chloric acid and magnesium powder:
Assay
UV-spectrophotometry
Storage
Store protected from light
Application
Vitamin P regulates vascular permeability, enhances
the action of ascorbic acid. Used for the prevention
and treatment of hypo-and avitaminosis of P vitamin,
and for the treatment of diseases associated with the
violation of vascular permeability and capillary lesions.
Produced in powder and tablets on 20 mg. Included in
the Table. "Ascorutin" (along with ascorbic acid and
glucose) and vikalin (bismuth nitrate basic, basic
magnesium carbonate, sodium bicarbonate, powders
of sweet flag (calamus) root and buckthorn bark, rutin
and Kelin).
Heterocyclic vitamins
Pyridine derivatives
the nicotinic acid, its amide (vitamin PP) and
oximethylpyridine vitamins (group В6 ) belong to the
vitamins of pyridine derivatives.
Nicotinic or β-pyridinecarboxylic acid was firstly
synthetically obtained by Huber in 1867-1870. Its
vitamin properties were found in 1937-1938. In the
natural materials nicotinic acid themselves does not
occur but nicotinamide occures, which is a part of
many enzymes. Thus, nicotinic acid is a pro-vitamin of
nicotinamide.
Nicotinic acid is obtained only synthetically.
Nicotinic acid obtaining
The main source of the obtaining of
nicotinic acid - an nicotine alkaloid, which is a
by-product of the tobacco production and the
anabasine alkaloid it is contained in anabazis wild growing plant in Central Asia. These
alkaloids are easily oxidized by various oxidants
to nicotinic acid:
Nicotinic acid (Acidum nicotinicum),
Vitamin РР, Vitamin В5, Niacyn (ДФУ)
N
COOH
Pyridine-3-carboxylic acid
CHARACTERS. Crystalline white powder. Soluble in
boiling water and boiling 96% alcohol, moderately
soluble in water, practically insoluble in ether.
Dissolves in dilute solutions of hydroxides and
carbonates of alkali metals.
Identification
1. Substance at the interaction with the cyanobromide
(cyanochloride) solution and aniline solution forms
a yellow color:
COOH
+
HC
BrSCN
+
N
+
+
-
+
C
CHOH
OH
O
SCN
COOH
C
C
H
C
H
C
CHOH
2H2O
2 H2N
+
COOH
+
O
C
C
H
NH2SCN
O
H
Br
N
HBr
H
C
COOH
N
C
H
C
H
C
H
C
C
H
N
H
+
2. Melting point, ІR-spectroscopy.
3. Un pharmacopoeia reaction :
а) Reaction of pyridine cycle with 2,4-dinitrochlorbenzene
(Cink reaction)
b) formation of copper nicotinate blue color:
COOH
2
COO
-
Cu2+
CuSO4
+
N
+
H2SO4
2
N
c) With copper sulfate and ammonium thiocyanide solutions green color:
COOH
4
+
COOH
Cu
CuSO4
N
N
4
COOH
Cu
N
4
(SCN)2
+ (NH4)2SO4
SO4 + 2NH4SCN
d) At the heating of the substance with anhydrous
sodium carbonate, there is a smell of pyridine:
Assay
1. Alkalimetry, direct titration, the indicator phenolphthalein. Parallel to conduct a blind test.
Е = М.м
COOH
+
N
COONa
+
NaOH
N
H2O .
2.
In the injection solutions (except nicotinic acid there is sodium
bicarbonate), the quantitative content of the drug is determined by a
coppermetry. In this case, to the solution of nicotinic acid to add a
solution of Copper sulfate, the precipitate is filtered and in the
filtrate there is determined the excess of CuSO4 by iodometric.
Indicator - starch. Parallel to conduct the control test. Е = 2 М.м
3. UV-spectrophotometry in the injection solution.
Storage
Store protected from light.
Application
Antipellagric medicine. Nicotinic acid has vasodilator and
hypocholesterolemic action, so it is prescribed for liver
disease, vascular spasm in the limbs, kidneys and brain, at
the infectious diseases.
Side effects: flushing, feeling a rush of blood to the head.
H.d. – 0,1 g; h.d.d. – 0,5 g.
Producing: tablets оn 0,05 g №50;
amp. 1% - 1,0 №10.
It is in the complex tablets “Nicoshpan”
Nicotinamide (Nicotinamidum) (UP)
Pyridine-3-carboxamide
CHARACTERS. Crystalline white powder or colorless
crystals. Easily soluble in water and ethanol. It has
basic properties. It is obtained by the interaction of
ammonia and ethylnicotinate.
Identification
Melting point.
2. IR-spectroscopy.
3. Ammonia evolving at the heating of the substance
with a sodium hydroxide solution:
1.
4.
Reaction of the formation of Schiff bases at the
interaction with cyanobromide reagent and aniline
(see nicotinic acid).
Un pharmacopoeia reaction.
а) At the heating with crystalline Na2CO3 – appearance
pyridine small:
5.
b) With CuSO4 and NH4SCN solutions appearance emeraldgreen color.
c) With 2,4-dinitrochlorbenzene and NaOH solution – redviolet color (on the pyridine cycle).
d) Dragendorff’s reagent (on the heterocyclic nitrogen atom).
Assay
Acidimetry in nonaqueous medium of the mixture of
anhydrous acetic acid and acetic anhydride , a direct
titration at the present of mercury (II) acetate, the indicator
- crystal violet (Е=М.м). Parallel to conduct a blind test.
Modified Kjeldahl method (determination of ammonia
after alkaline hydrolysis.
Storage
Store protected from light.
Application
Antipellagric medicine.
It is included in the kodegidraz enzymes that
transfer hydrogen, take part in ox-red reactions
in
the
body.
Daily
requirement
15 mg.
Assign at pellagra, liver disease, gastritis with
low acidity, chronic colitis. Nicotinamide has no
vasodilatory action.
producing: tab. оn 15 mg; amp. 1% - 1,0 №10.
It is in polyvitamins.
Oxymethylpyridine vitamins (vitamins of
В6 group)
Vitamins of В6 group are represented by the related
substances: pyridoxol (pyridoxine), pyridoxal and
pyridoxamine, consistently converted into each other:
Pyridoxine hydrochloride (UP)
(Pyridoxini hydrochloridum) viyamin В6
(5-hydroxy-6-methylpyridine-3,4-diyl)-dimethanol h/ch оr
3,4-di (oximethyl)-5-oxi-6-methylpyridine h/ch
CHARACTERS. Crystalline powder of white or nearly
white color. Easily soluble in water, slightly soluble in
96% alcohol. Melts at about 205 ° C with
decomposition.
Storage
Store in tightly closed container of a dark
glasses, in a cool place.
Obtaining of Pyridoxine hydrochloride
Contained in the raw grain cereals,
vegetables, meat, fish, cod liver oil and cattle,
yeast, egg yolk, etc.
Now pyridoxine is obtained only by a
synthetic way. Precursor for the synthesis of
pyridoxine by the method of M.A.
Preobragensky is monochloracetate acid.
Identification
1. According to the physico-chemical constants: IR and
UV spectroscopy, TLC (as a developer using 2,6dichlorquinonechlorimide):
2. It giver reaction of chlorides.
3. Un pharmacopoeia reaction :
а) With silicontungstenic and phosphorustungstenic
acids it is formed sediments (on the presence of
pyridine bases).
b) At the interaction with FeCl3 solution it is formed a red
coloration, which disappears when you add sulfuric acid
(reaction to a phenolic hydroxyl group):
c) Pyridoxine takes part in the azoconnection reacts with diazonium
salts. Formed the azo dyes yield colored complexes with salts of
heavy metals, particularly zinc:
Assay
1. Acidimetry in non-aqueous medium in a mixture of
formic acid and acetic anhydride. Equivalence point
is determined by potentiometric method. E = М.м.
Conduct a blind test. (UP, addition 1)
2.
Alkalimetry, direct titration in a mixture of 0.01 M
hydrochloric acid solution and 96% alcohol.
Equivalence point is determined by potentiometric
method. (UP). Е = М.м.
3.
Alkalimetry, direct titration. Indicator - bromothymol
blue. E = A.m. Cl. Calculations are carried out on the
chlorine content, which in terms of dry matter should
be 17,1-17,35%.
1) Acidimetry in nonaqueous medium, a direct
titration at the present of mercury (II) acetate, the
indicator - crystal violet (Е=М.м).
Purity test
Specific impurity: methyl ether of pyridoxine. It is determined by the
using of a 2,4-dichlorquinonechlorimide - after binding of pyridoxine
by a boric acid to a complex, which does not give the reaction of the
dye:
An the presence of impurities appears a blue color
layer of butyl alcohol.
Application
Pyridoxine is in codecarboxilase. Daily requirement
for healthy humans is 2 mg. When hypo-and
avitaminosis there is observed characteristic
dermatosis (erythredema), swelling, degenerative
changes in the nervous system, etc.
Applied in various forms of Parkinson's disease,
chorea, acute and chronic hepatitis, toxicosis during
pregnancy, anemia, radiculitis, neuritis, neuralgia and
other nervous diseases.
producing: tab оn 0,01 g №10; аmp 1% - 1,0 №10; 2,5%1,0 №10; 5% - 1,2 №10.
You can not mix in the same syringe В1 and В12.
Included in the medicines of B vitamins: magne-B6,
Neyrorubin, Neurobex, Neurovitan, neuron, multi-tabs
B-complex.
Antivitamins
Investigation of the relationship between chemical
structure and vitamin activity allowed to establish for
each vitamin, one or more antivitamin. They tend to
differ from vitamins structure of a single functional
group.
In some antivitamin structure differs significantly from
the vitamins. For example, antivitamin
naphthoquinones (neodicoumarin, phenyline).
Antivitamin in biocatalytic reactions behave as
competitive inhibitors. The essence of their actions
that they form a kind of psevdoenzymes that suppress
the action of these enzymes or displace vitamins from
enzymatic systems. This leads to the using of
antivitamin as drugs for the treatment of many
Vitamins
Antivitamins
L-Ascorbic acid
D-Ascorbic acid
Pantothenic acid
ω-methylpantothenic acid
Naphthoquinones
Neodicoumarin
Nicitinamide
Pyridine-β-sulfoacid
β-acetopyridine
Pyridoxine
5-desoxipyridoxal
Thiamin
oxithiamine
Folic acid
Aminopterine
Riboflavin – 6,7-dimethyl-9-(1’- 7-methyl-8-chlor-10-(1’-DD-ribithyl)-isoaloxasine
ribithyl)-isoaloxasine
7- methyl -8-аmino-10-(1’-Dribithyl)-isoaloxasine
Cyanocobalamin
2,5-dimethylbenzimidazole
Derivatives of pyrimidine and
thiazole
Molecule of pyrimidine-thiazol vitamins (vitamins B1 thiamines) consists of two heterocycles - pyrimidine (A)
and thiazole (B) connected by a methylene group:
In medical practice used thiamine hydrobromide, thiamine
hydrochloride, diphosphate ester of thiamine
hydrochloride (cocarboxylase).
Preparations of vitamin В1
Thiamine hydrobromide
(Thiamini
hydrobromidum) (SPhU)
Thiamine hydrochloride
(Thiamini
hydrochloridum) (SPhU)
3-[(4-Amino-2-methylpyrimidine-5-yl)methyl]-5-(2hydroxyethyl)-4-methylthiazole
bromide hydrobromide
3-[(4-Amino-2-methylpyrimidine-5-yl)methyl]-5-(2hydroxyethyl)-4-methylthiazole
chloride hydrochloride
Vitamin В1 is the first vitamin, which pioneered the
opening of vitaminology science .
For the first time it was identified from the rice bran
(Funk in 1912 y.). This substance in small doses cured
polyneuritis of pigeons and because its structure contains
sulfur atom, called thiamine.
Most contained in the cereal (grain) plants, yeast, egg
yolks, ox liver. Extraction from natural sources is difficult
with low output (from 1 t of yeast - 0,25 g of vitamin В1).
For the medical purpose it is received synthetically, at the
first pyrimidine and thiazole compounds should be
extracted separately, then they are condensed .
Thiamine belongs to the aminoalcohol of heterocyclic
series (availability of carbonyl and amino-groups ).
Properties of thiamines
Thiamine
hydrobromide
Thiamine
hydrochloride
The crystalline powder of
The crystalline powder of
white or white with
white or almost white or
yellowish tint with a
colorless crystals. Easily
specific smell. Easily
soluble in water, soluble in
soluble in water, little
glycerin, slightly soluble in
soluble in 96% alcohol,
96% alcohol. Hygroscopic.
practically insoluble in
ether.
This compounds are stable only in acidic environment In the
neutral and alkaline environments decompose with rupture
of thiazole cycle and formation of mercapto group.
Identification of thiamines
1.
2.
3.
Thiamine hydrobromide
IR-spectrophotometry.
Thiochrome test.
Reactions on bromides.
1.
2.
3.
Thiamine hydrochloride
ІЧ-spectrophotometry.
Thiochrome test.
Reactions on chlorides.
Unpharmacopoeial reactions
а) With solutions of FeCl3 and K3[Fe(CN)6] a blue coloration
of Berlin blue formed.
b) At the melting with crystalline NaOH or metallic sodium
sulfide ions formed, which can be detected by the reaction
with sodium nitroprusside (red-purple coloration).
c) Thiamine can be quantitatively precipitated from the
solutions by the usage of some general alkaloid reagents
(Dragendorff, Bertran, Sheibler, picric acid, p-
Thiochrome test
Thiamine is oxidized by the alkali solution of potassium
ferricyanide with the thiochrome formation (bright
yellow substance), which is extracted by isoamyl or
butyl alcohol - alcohol layer gives blue fluorescence in
UV light (λ = 365 nm):
Quantitative determination of thiamine
hydrochloride and hydrobromide
1.
Thiamine h/br. (SPhU). Acidimetry in non-aqueous
environment in the presence of mercury (II) acetate .
Equivalent point is determined by potentiometric
method:
Е = ½ М.m.(C12H18Br2N4OS)
2.
3.
Thiamine h/chl. (SPhU). Alkalimetry in the mixture of 0,01 М
chloride acid solution and 96 % alcohol. Titrant – 0,1 М
NaOH solution. Equivalent point is determined by
potentiometric method. Volume of titrant between two
potential jumps on the titration curve is taken in the
calculation. Е = ½ М.m.
Thiamine h/chl.(SPhU addition 1). Acidimetry in non-aqueous
environment in the mixture of formic acid and acetic
anhydride. Equivalent point is determined by potentiometric
method. Е = ½ М.m.
4.
5.
6.
7.
8.
Gravimetry after precipitation of the drug by silicon tungsten
acid. Sediment composition: SiO2•12WO3• 2C12H17BrN4OS або
SiO2•12WO3• 2C12H17ClN4OS.
Alkalimetry, direct titration, indicator – bromothymol blue
orphenolphthalein. Е=М.m.
Argentometry by Fayans method, indicator – bromophenol blue.
Е=1/2 М.m.
Fluorimetry (by the intensity of thiochrome fluorescence).
Argentometry after the neutralization of the substance solution
with alkali. Analytical weight of thiamine bromide is titrated by
sodium hydroxide solution to the blue-green color, indicator –
bromothymol blue .
Then solution acidified by nitrate acid, add indicator – iron (III)
ammonium sulfate and 0,1 ml of 0,1М ammonium thiocyanate
solution – red color appears due to the formation of iron (III)
Reaction mixture is titrated by 0,1 М silver nitrate solution:
In the equivalent point excess of silver nitrate reacts with
iron (III) thiocyanate – solution becomes colorless:
The content of thiamine bromide is calculated by the
difference of volumes of silver nitrate, ammonium
thiocyanate and sodium hydroxide. Е = М.m.
Storage of the thiamine preparations
In airtight containers, that protect from the action of light. Not
allowed contact with metals to prevent the reduction to
dihydrothiamine:
Application of the thiamine
preparations
В1 plays an important role in human body. Is part of
coenzyme – cocarboxylase. While lack of vitamin B1
carbohydrate metabolism disorder arising, lactic and
pyruvic acid accumulate in the tissues, and therefore may
be neuritis and disorders of the heart. Thiamine affects on
protein and lipid metabolism, participates in the regulation
of water exchange.
Daily demand 2 mg (1 vg of the drug – 330 IU).
Avitaminosis –a beriberi disease, hypovitaminosis disorders of the nervous system.
Used for treatment of hypo- and avitaminosis of this
vitamin and diseases associated with dysfunction of the
nervous system.
Thiamine hydrobromide due to its higher molecular
weight are taken in large doses (1 mg of thiamine
hydrochloride is responsible by the activity to 1,29 mg
of thiamine hydrobromide).
Issue: Thiamine hydrochloride – dragee by 0,002 g,
amp. 5%-1,0 №10; thiamine hydrobromide – dragee by
0,0026 g №50.
Included in multivitamin preparations and vitamin of B
group (neurobex, neuron, neurovitan, neurorubine,
multi-tabs B-complex).
It is not recommended to enter at once parenterally with
B6 and B1 vitamins (delay esterification of thiamine by
phosphate acid) and B12 (enhances allergic effect of
thiamine) and mixed in one syringe vitamin B1 with
penicillin or streptomitsin (decomposition of antibiotics)
and nicotinic acid (thiamine decomposition).
Cocarboxylase
(Cocarboxylasum) CCB
Hydrocloride of thiamine diphosphate ester
CCB – freeze (lyophilization) dry white porous mass with
low specific smell and bitter-sour taste. Easily soluble in
water, sparingly soluble in ethanol.
Decomposes at the heated above 35°С.
Store in a dark place at a temperature less than 5°С.
CCB –coenzyme of enzymes involved in carbohydrate
metabolism. In the compound with proteins and magnesium
ions is a part of the carboxylase enzyme that catalyzes
carboxylation and decarboxylation of a-ketoacids .
In connection with the lack of CCB at the beri-beri diseases aketoacids (especially pyruvic and СН3СОСООН acids)
accumulate in the tissues.
Assign it foe the treatment of arrhythmia, coronary circulation
failure and other cardiovascular diseases, diabetes and various
pathological processes associated with deterioration of
carbohydrate metabolism.
Enter by i/m, i/v, s/c way by 0,05-0,1 g 1 time per day.
Issue: sealed ampoules by 0,05 g of sterile powder, which
before usage (ex tempore) is dissolved in 0,5% novocaine
solution or 0,9% sodium chloride solution.
Derivatives of pterin
Pterin vitamins, which include folic acid (vitamin Вс),
contained in green leaves of spinach, parsley, lettuce, in
legume and cereal crops (wheat, rye, corn), as well as in
yeast, liver.
The basis of chemical structure of the data vitamins is a
pteridine kernel which is a condensed system of pyrimidine
(A) and pyrazine (B) cycles. Derivative of pteridine 2amino-4-oxypteridine is called pterin.
Folic acid
(Acidum folicum), vitamin Вс (SPhU)
(2S)-2-[[4-[[(2-Amino-4-oxy-pteridine-6yl)methyl]amino]benzoyl]amino]pentadioc acid
Name of the vitamin is derived from the Latin word folium – leaf.
Folic acid is in nature both in free state and as polyglutaminates
in which there are additional glutamic acid residues.
Extraction of folic acid
(method of А.V. Truchanova and B.А. Kirsanova)
Condensed equimolar quantity of 2,5,6-tri-amino-4oxypirimidine hydrochloride, p-aminobenzoyl-L(+)glutamic acid and 2,3-dibromopropionic aldehyde:
Storage of folic acid
In airtight containers, in the place protected from light.
Properties of folic acid
Crystalline yellowish or orange powder. Practically
not soluble in water and most organic solvents
(different from other vitamins). Soluble in dilute
acids (the presence of nitrogen atoms of amine
nature) and alkali (availability of free carboxyl
groups). Decomposing under the action of light,
hygroscopic.
Folic acid molecule consists of three main parts: 2amino-4-oxypteridine (pterin), p-aminobenzoic
acid and associated with this acid residue of
glutamic acid.
Folic acid is an amphoteric compounds: basic
properties is caused by the nitrogen atoms of the
pteridine molecule, acidic - the carboxyl groups
and hydroxyl group in position 4.
Identification of folic acid
By the physico-chemical constants: specific rotation, by
liquid chromatography method, TLC.
Unpharmacopeial reactions:
А) at the adding of potassium permanganate to the drug
solution in hydrochloric acid (with following selection of
its excess by hydrogen peroxide) p-aminobenzoylglutamic
and pterine-6-carboxylic (pteric) acid are produced. The
last has a much stronger blue fluorescence than folic acid,
and its use for fluorimetric quantification of the drug.
b) determination of UV-spectral characteristics of folic acid.
c) due to its acidic properties folic acid with salts of heavy
metals forms insoluble colored complexes; with CuSO4 –
green precipitate, with Co(NO3)3 – dark yellow precipitate,
with FeCl3 – red-yellow precipitate. The general formula of
these salts:
Assay of folic acid
1.
2.
Liquid chromatography.
Polarographic method. Is used the folic acid ability to
recover in the medium of sodium carbonate to 7,8dyhydrofolic acid which is easily oxidized to folic even by
atmospheric oxygen, polarographic cell is constantly
blowing by nitrogen.
3.
Photocolorimetric method. In the core of method is folic
acid oxidation by potassium permanganate with the
following formation of p-aminobenzoylglutamic acid, its
diazotation and azoconnection with N-(1-naphthyl)ethylenediamine dyhydrochloride. As a result formed
colored in purple color azo dye, the intensity of its
coloration in a solution is determined by photocolorimeter
at =550 nm.
Application of folic acid
Folic acid is involved in the process of blood formation, so it is
called antianemic factor. Together with vitamin В12 it stimulates
erythropoiesis, is involved in the synthesis of amino-acids
(methionine, serine, etc.), nucleic acids, purine and pyrimidine
metabolism and in choline metabolism. In the body is redused to
tetrahydrofolic acid - coenzyme that participates in various
metabolic processes.
Daily demand of the folic acid for a healthy human is 0,2 - 1 mg.
Its deficiency leads to anemia.
To prevent a lack of folic acid at the unbalanced or poor nutrition
take 20-50 mcg inside daily, during pregnancy - 400 micrograms
per day and lactation - 300 mcg.
Issue: tabl. by 0,001 g and 0,005 g № 50.
Used for increased erythropoiesis, in certain types of anemia,
including anemia and leukopenia caused by drugs and ionizing
radiation, chronic gastroenteritis and tuberculosis of intestine.
Derivatives of isoalloxazine
Isoalloxazine –heterocyclic system, which consists of
condensed pyrazine, pyrimidine and benzene cycles, that is
derived from benzopteridine. Pyrimidine nucleus of
isoalloxazine has character of lactam cycle because it
contains two keto-groups :
Benzopteridin e
isoalloxazine
Detection of vitamin properties of flavin associated with the
presence in the molecule extremely labile group with two
conjugated double bonds in isoalloxazine nucleus. This
group of atoms causes the redox properties of riboflavin.
Riboflavin (Riboflavinum)
vitamin В2 (SPhU)
7,8-Dimethyl-10-[(2S,3S,4R)2,3,4,5-tetrahydroxy-пpentyl]
benzo[g]pteridine2,4(ЗH,10H)-dion,
or 6,7-dimethyl-9-(1’-Dрibityl)-isoalloxazine
At the first isoalloxazine vitamins (vitamin B2) was
allocated from whey (because it is also called "laktoflavin).
Name of vitamin B2 "Riboflavin" comes from the fact that it
has a residue of polyhydric alcohols of the ribose original,
and its solutions are yellow (Latin flavus - yellow).
Riboflavin is very common in plant and in animal
products: contained in the milk serum, liver, kidney,
brewer's and baker yeast; in grains - millet, barley; in
vegetables - spinach and tomatoes.
For extraction of 1 g of the drug should be processed 5,4
tons of whey, so now vitamin B2 is synthesizeed from Dribose, о-4-xylidine and barbituric acid.
Characters. Yellow or orange-yellow crystalline powder.
Very few soluble in water, hardly soluble in 96% alcohol,
ether, acetone, chloroform. Easily soluble in chloride
(forms salts) and acetic acid. Solutions decompose under
the influence of light, especially in the presence of alkali.
Detects polymorphism.
Identification of riboflavin
1.
2.
By the physico-chemical constants: the specific rotation,
infrared spectroscopy, TLC.
Solution of the substance in the light that passes through
it, has a pale greenish-yellow color, and in reflected light
- an intense yellow-green fluorescence, which
disappears at the adding of mineral acid or alkali (in
acidic medium on the light forms riboflavin forms
lumichrome (6,7-dymethylalloxazine) - a colorless
substance that breaks down into ethanol and chloroform
with the appearance of blue fluorescence, in alkaline
medium on light riboflavin forms lumiflavin (6,7,9trimethylalloxazine), which solution has the same color
and fluorescence as riboflavin, but soluble in
chloroform).
3.
At the riboflavin reduction by sodium hydrosulfite and
fluorescence and coloration of aqueous solution disappear (a
colorless compound formed - leukoriboflavin):
Unpharmacopoeial reaction:
a) at the adding of sulfate concentrated acid to riboflavin red
coloration appears, which becomes yellow after the adding of
water.
b) with a silver nitrate solution orange-red coloration forms
(presence of imide group).
4.
Test on purity
Determined lyumiflavin that formed as a result of
changes in the chemical structure of matter under the
influence of light and alkaline environment.
Determination of the lyumiflavin impurity based on its
solubility in chloroform (in chloroform riboflavin is
insoluble) - color of the filtrate should not exceed the
standard(SPhU).
Determination of the lyumiflavin impurity conducted by
thin layer chromatography(SPhU, additions).
Storage
In airtight containers, in the place protected from light.
Assay of riboflavin
1.
2.
3.
4.
5.
UV spectrophotometry (SPhU). Determination of the
optical density is conducted at the weakened
transmitting light in aqueous solution, acidified by
acetic acid at =444 nm. Riboflavin content is
calculated using the specific absorption rate, which
equals 328.
Photocolorimetry.
Fluorimetry.
Alkalimetry by substituent after the interaction with
silver nitrate solution. Е = М.m.
Periodate oxidation (Malaprad’s reaction). Methodic is
based on the ribityl fragment of riboflavin molecule
oxidation with formation of formic acid.
Formic acid, which eliminated as a result of reaction, is
titrated by alkalimetry method :
НСООН + NaOH → НСООNa + Н2О
According to another method after the action of periodate
to the solution is added sodium iodide and sulphate acid:
5 NaI + NaIO3 + 3 H2SO4 → 3 I2 + 3 Na2SO4 + 3 H2O
Iodine that allocated by the reaction is titrated by the
standard solution of sodium thiosulfate.
6. Estarification byconcentrated sulfate acid. Due to the
hydroxyl groups are formed by mono-, di-, tri- and
tetrasulfoxyl esters are formed. Then by potentiometric
titration with KOH solution determine an excess of sulfate
acid. The reaction proceeds in a stechiometric ratio 1 : 3.
Application
Plays an important physiological role, because is a part of
the oxidativ cell enzymes as riboflavin-phosphate ester.
Daily demand – 2 mg. Hyporiboflavinose is characterized
by deterioration of appetite, weight loss, sores in the corners
of mouth; ariboflavinose - conjunctivitis, clouding of the
cornea and lens its..
Vitamin В2 is used orally in doses of 5-10 mg per day
(depending on the degree of disease) at ariboflavinose,
conjunctivitis, irytah, keratitis, radiation sickness and others.
Issue: tabl. by 0,002 g; 0,005 g; 0,01 g; 0,01% eye drops; is
a part of riboflavin mononucleotide (riboflavin-5'monophosphate sodium) – amp. 1%-1,0 №10.
Corrine derivatives
Corrine vitamins (group В12) were found in natural
products of the animal origin, mainly in the internal
organs. So, the richest source of vitamin B12 are fish
entrails, high content of this vitamin is in the whale liver
and the highest content meat is in the meat of molluscs. In
human and animal B12 is synthesized by microflora of
intestine and accumulates in the liver, kidney, intestine
walls.
Vitamin В12 (cyanocobalamine) is extracted from the
waste of the production of streptomycin and
chlortetracycline antibiotics. Another source - sewage
(waste products of actinomycetes, bacteria, blue-green
algae), from this sourse vitamin B12 is allocated by
adsorption or extraction.
Cyanocobalamin
(Cyanocobalaminum) vitamin В12
(SPhU)
α-(5,6-dimethylbenzimidazole-1yl)cobamide cyanide
Corrine
Cyanocobalamin molecule consists of two main parts.
First
nucleotide
containing
5,6dimethylbenzimidazole
associated
with
Dribofuranose, which, in turn, linked by etheric bound
with phosphate acid. Nucleotide connected with
macrocyclic corrine system (second part) by peptide
bond. Nitrogen atom of 5,6-dimethylbenzimidazole in
position 3 bounded by coordination bond with cobalt
atom. Cobalt forms a chelate compound with cyanogroup and with nitrogen atoms and of hydrogenated
pyrrole cycles of corrine system.
Positive charge of cobalt ion is neutralized by
negatively charged phosphate acid anion. Therefore,
cyanocobalamin is not only a chelating compound, but
an internal salt.
Properties of cyanocobalamin
Crystalline powder with dark red color, odorless,
hygroscopic. Sparingly soluble in water, soluble in 95 %
alcohol, practically insoluble in ether, chloroform,
acetone. The anhydrous substance is very hygroscopic
At the heating above 300°С decomposes. Stable at рН=46. Easily decomposed in an alkaline environment.
СN-group in the molecule of vitamin В12 can be replace
by
the
ОН-group
(oxycobalamin)
or
NO2
(nitrocobalamin). Both products are converting to a group
of vitamin В12.
At the heating of cyanocobalamin solution with HCl
ammonium
chloride,
5,6-dimethylbenzimidazole,
aminoisopropanol, cobalt chloride,
cyanic acid are
formed.
Antianemic action associated with the presence of 5,6dimethylbenzimidazole in the molecule structure.
Identification of cyanocobalamine
Determination of UV-spectral characteristics.
TLC.
Cobalt ions are determined after the mineralization by
alloying with potassium hydrosulfate and interaction
with sodium 1-nitroso-2-naphthol-3,6-disulfonate - a red
color of internally complex salts of cobalt appeares.
Cobalt ion can be detected after evaporation and
roasting of 0,25 mg of cyanocobalamin with 10 mg of
potassium sulfate and 2 drops of 15 % sulfate acid.
Saturated solution of ammonium thiocyanate in
acetone is added to the residue; blue-green coloration
appears :
Со2+ + 2 NH4SCN → Со(SCN)2 + 2 NH4+
Detection of cyano-group. Analytical weight of
cyanocobalamin is heated in the test-tube with oxalic
acid, under the action of this acid cyanic acid
eliminates, which is detected with filtration paper
soaked by the solution of benzidine and copper (ІІ)
acetate, as a result blue complex compound formes.
Assay
The method of UV-spectrophotometry.
Storage
In airtight containers, in the place protected from light.
Application of cyanocobalamin
 Vitamin В12 is a growth factor necessary for normal
hematopoiesis and maturation of erythrocytes. He participates in
the formation of choline, methionine, nucleic acids, shows a
positive effect on liver function and nervous system.
 Daily demand for healthy person – 10-20 mcg.v This quantity of
vitamin is not produced in the intestine and should be
complemented by the products of animal origin
 Apply at the malignant anemia, various forms of anemia, liver
disease, nervous system, skin diseases and others.
 Issue: solution for injection 200 mcg (0,02%) or 500 mcg
(0,05%) 1,0 №10
Multivitamin drugs
In nature vitamins commonly found in the form of various
combinations. Herbal products often contain vitamins of group
B, vitamin C and others. The combination of vitamins is also
found in animal products.
. In many cases, vitamins mutually reinforce physiological
effects that they have. For example, the effect of vitamin P on
vascular permeability amplified by ascorbic acid, mutually
amplifying effect on hematopoiesis of folic acid and
cyanocobalamin.
In some cases, toxicity of vitamins is reduced at their combined
application. For example, vitamin D toxicity is reduceing by
vitamin A. For example, vitamin D toxicity is reduceing by
vitamin A. Vitamins can also detect antagonistic effect (nicotinic
acid slows the lipotropic action of choline).
Vitamins participating actively in various biochemical processes,
if they are associated and show a stronger complex biological
action that is served for the combined usage in both cases for the
preventive and therapeutic purposes.
Multivitamin drugs have different compositions (some
vitamins alone or in combination with microelements) and
issued in the form of various dosage forms: tablets,
“effervescent” tablets (upsavit, supradine) tablets for
chewing (multi-tabs, jungle), beans (sob) , syrups
(multivitamol), gels (Kinder-biovital), solution for injection
(nerviplex (В1, В6, В12)).
Ukrainian multivitamin drugs: revit (А, В1, В2, С), hexavit
(revit+ В6, РР), undevit (hexavit+ Е, Р, Вс, В3), decamevit
(А, В1, В2, В6, В12, РР, С, Е, Р, Вс, methionine), complevit
(В1, В2, В6, В12, РР, С, Е, Вс), quadevit (decamevit + В3,
glutamic acid, fitine, KCl. CuSO4), vitam (В1, В2, В6, РР,
В3,mefenamic, Fe, Zn, Mn, Cu, Co, Cr).
Multivitamin preparations of the foreign origin: Vitrum
vitamins (Kids, Junior, Beauty, Prenatal, Energy, Cardio,
etc..) Centrum, multi-tabsy, Duovit, Pikovit, Jungle, Unicap,
Pregnavit, Oligovit, Theravit, Supradyn, Kinder-biovital and
others.
Thanks for attention!