Transcript 4. MP and MPM that contain iridoids

Terpenoids(isoprenoids).
Chemical analysis of
iridoids. Analysis of
herbs and medicinal
herb material containing
iridoids
The terpenoids sometimes called
isoprenoids, are a large and diverse class
of naturally occurring organic chemicals
similar to terpens, derived from five-carbon
isoprene units assembled and modified in
thousands of ways.
Terpenoids are extraordinarily diverse but they all
originate through the condensation of the
universal phosphorylated derivative of
hemiterpene, isopentenyl diphosphate (IPP) and
dimethylallyl diphosphate (DMAPP) giving geranyl
pyrophosphate (GPP).
In higher plants, IPP is derived from the classic
mevalonic acid pathway in the cytosol but from the
methylerythritol phosphate pathway in plastids. It
is generally accepted that the cytosolic pool of IPP
serves as a precursor of sesquiterpenes,
triterpenes, sterols and polyterpenes whereas the
plastid pool of IPP provides the precursors of
mono-, di- and tetraterpenes
A rational classification of the terpenes has been
established based upon the number of isoprene
(or isopentane) units incorporated in the basic
molecular skeleton:
Importance of terpenoids
 Plant terpenoids are used extensively for their
aromatic qualities. They play a role in traditional
herbal remedies and are under investigation for
antibacterial, antineoplastic, and other pharmaceutical
functions.
Iridoids
 Iridoids are a class of secondary
metabolites found in a wide variety of
plants and in some animals. They are
monoterpenes biosynthesized from
isoprene and they are often
intermediates in the biosynthesis of
alkaloids.
Chemically, the iridoids usually consist of a
cyclopentane ring fused to a six-membered
oxygen heterocycle. The chemical structure is
exemplified by iridomyrmecin, a defensive
chemical produced by the iridomyrmee genus, for
which iridoids are named.
Bioactivities of iridoids
 Iridoids are found in many medicinal plants and
may be responsible for some of their
pharmaceutical activities. Iridoids exhibit a wide
range of bioactivities including stimulation of
secretions in the gastrointestinal tract, choleretic,
antimicrobial, cardiovascular and sedative
(valeopotriates), antihepatotoxic, diuretic
(catalpol), hypoglycemic, analgesic, antiinflammatory, antimutagenic, antispasmodic,
antitumor (valtrate), antiviral, immunomodulator,
and purgative activities.
Classification
 1. Cyclopentan C8,C9,C10 and C14 types
(Loganin, aucubin).
 2. Secoiridoids. Cleavage of bound in
thecyclopentane ring gives rise to secoiridiids.
(Secologanin, gentiopicroside, oleuropine)
 3. Iridoids of plant from family Valerianaceae
Bicyclic monoterpens or valepotriates
(‘Valeriana – Epoxy – triester’) Valtrate,
dihydrovaltrate.
 4. Iridoids-alcaloids – complex of indole
alcaloids containing as non-amine part iridoid
FOLIA MENYANTHIDIS
TRIFOLIATAE
Menyanthes trifoliata Bogbean
Menyanthaceae
BAS: Leaves contain bitter
amorphous glycoside of meniantin, at a
hydrolysis fissioning on glucose and
meniantol; alkaloid of gencianin,
flavonoids of rutins and giperozid,
ascorbic acid, and also tannic matters to
3%. Roots contain glycoside is a
meliatin, tannic matters, inulin, pectin
matters and tracks of alkaloids.
Pharmacological activity: natural physiological
stimulant of secretion of saliva, gastric juice, bile and digestive enzymes; protivoskleroticheski
operates; the presence of organic compounds of iodine in the leaves of watch hinders to the
accumulation of cholesterol in an organism
Dosage forms: Water extract. Enters in the complement of appetizing,
sedative collections.
HERBA CENTAURII
Centaurium erythraea (С. minus, C.
umbellatum)
Centaurium pulchellum (SW) Druce
Gentianaceae
BAS:. A plant contains 0,6-1% alkaloids,
among them basic gencianin (eritricin):
glycosides (genciopikrin, eritrocentaurin,
eritritaurin); flavonovyy glycoside of
centaurin, oleanolovuyu and ascorbic acids,
essential oil, resins
Pharmacological activity: Preparations of centaury as bitter taste is excited
appetite, strengthen the secretion of digestive glands, strengthen
zhelcheotdelenie, possess poslablyayuschimi and by protivoglistnymi
properties (genciopikrin).
Dosage forms: A grass of centaury is in packs. Extract. Collections
appetizing and stomach.
The dry rhizome and
roots of Gentiana lutea
BAS: gentiopicrin, gentisin, The root
also contains from 12 to 15 per cent.
of glucose (gentianose), but is
remarkable in that it contains no
starch, calcium oxalate, or tannin.
Preparation of Gentisic Acid : The alcoholic extract is washed with water, then
with ether. The residue dissolved in alcohol yields the acid on evaporation.
ACTION AND USES.—Simple bitter tonic, long known and very valuable.
Dose: 5 to 30 gr. (0.3 to 2 Gm.).
VIBURNUM OPULUS—CRAMP BARK
The dried bark of Viburnum opulus
BAS: A brown resin, a bitter principle
(viburnin), valerianic acid, tannic acid,
oxalic, malic, and citric acids,
sulphates, and chlorides, opulus iridoid
ACTION AND USES: Diuretic, and a tonic and
sedative to the uterine and ovarian nerve centers; used in threatened abortion.
Dose: 30 to 60 gr. (2 to 4 Gm.). Claimed to be antispasmodic, hence the name
cramp bark. Dose: 30 gr. to 2 dr. (2 to 8 Gm.).
VALERIANA—VALERIAN
rhizome and roots of
Valeriana officinalis
BAS: Besides the common vegetable
principles, it contains a terpene,
isovaleric acid, and a volatile oil of
complex constitution, consisting mainly of
an alcohol, borneol; its ether, and its
formic, acetic, and valerianic acid
esters, which are gradually decomposed
on exposure, liberating the acids.
This oil (Oleum Valerian.,)
ACTION AND USES.—Gentle nerve stimulant and
antispasmodic, employed in hysterical disorders.
Dose: 15 to 60 gr. (1 to 4 Gm.).
Radices Taraxaci
Taraxacum officinale- Dandelion
Asteraceae
BAS: Taraxacin (a bitter principle),
taraxacerin,resin, inulin, sugar, and
mucilaginous substances. Recent investigations
have shown the existence of an alkaloid.
Preparation of Taraxacin.—Treat decoction with
animal charcoal, wash the latter with water, and
dissolve out bitter principle with boiling alcohol;
evaporate. It has not been proven that this is
crystalline. Composition uncertain.
ACTION AND USES.—Deobstruent, tonic. As a remedial agent
dandelion root has not been properly appreciated, possibly because it is
such a common weed. It is worthy of more study on the part
of pharmaceutical chemists and clinicians. The liquid extract and
extract are used in hepatic disorders.