PCOG
PCOG
PCOG
− Phenol group
− compounds that yield one or more sugars among the product
of hydrolysis CARDIAC GLYCOSIDES
− A glycoside is any molecule in which a sugar group is bonded − Related to steroids, CPPP nucleus
through its anomeric carbon to another group via glycosidic − Sugar component is attached on the 3 position of the CPPP
bond. nucleus
o Cyclo, pentano, perhydro, phenanthrene
In aqueous solution hexoses and pentoses will cyclize, forming − 2 aglycone
alpha (a) and beta (B) forms o (1) cardenolides
o (2) bufadienolides (discovered from BUFALIN
− Trivial names have an “in” ending and the names indicate the isolated from the skin of toad)
source of glycosides
− Examples: 1.LEIBERMANN-BURCHARD TEST
o digitoxin — from Digitalis − Tests the cardenolides/ bufadienolides
o Salicin from Salix
o Prunasin from Prunus 2.KEDDE REACTION
− Tests the presence of the lactone ring
− Systematic Names are usually formed by replacing the “ose” − Detect the presence of cardiac glycosides
suffix of the parent sugar with “oside”. The anomeric prefix (a-
or b- )and the configurational prefix (D or L) immediately 3.KELLER-KILIANI
precede the sugar stem name, and the chemical name of the − 2-deoxy sugars
aglycone precedes the name of sugar.
− Example: Salicin – o – hydroxy – methylphenol B-D-
glycopyranoside CARDIAC GLYCOSIDES: ACTION
− The most frequently occurring sugar is B-D- glucose, although − Inotropic effect – the ability to increase the force of systolic
rhamnose, digitoxose, cymarose and other sugars are contraction
o Can increase bp
component of glycosides
− Depletion of Potassium ions increases Digoxin Toxicity
− Glucoside – when the sugar formed is glucose
− Glycoside – when other sugar other than glucose is produced.
1.DIGITALIS (without arrythmia)
− AN ARRYTHMOGENIC
GLYCOSIDES: COMPONENTS
− SOURCES
− Aglycone, aglycon, or genin — non sugar component of
o Foxglove (D. Purpurea)
glycosides
o Grecian foxglove (D. lanata)
− Glycone — sugar component
SCROPHULARIACEAE (Active Glycosides)
GLYCOSIDES: IMPORTANCE
DIGITALIS PURPUREA DIGITALIS LANATA
− Involved in its regulatory, protective and sanitary functions of
Digitoxin Digoxin
plants
Gitaloxin Desacetyl Lanatoside
− Therapeutic agents Gitoxin (deslanoside)
4.Rhubarb
− Rheum officinale; Rheum
− R. palmatum; Chinese rhubarb
− R. emodi; Himalayan Rhubarb
− R. webbianum; Indian Rhubarb
− Use: Drastic cathartic
5.Senna
− Cassia acutifolia; Alexandria senna
− Cassia angustifolia; Tinnevelly senna ( Fam. Fabaceae)
− Use: - Cathartic
− Senna is graded according to the size of the leaf and the color
of the leaflets:
− Dimeric glycosides- principal active constituents of senna
whose aglycones are composed of aloe-emodin and/or rhein
− Sennosides A and B pair of stereoisomers whose aglycones are
rhein dianthrone (sennidin A and B) Sennosides C and D are
minor constituents having dimeric aglycone Senna pods also
contain useful, active glycosides; some of the primary
glycosides in the pods have as many as 10 sugar molecules
attached to a rhein dianthrone nucleus
− Blue green —best grade, yellowish — poorest
− Cultivated on wet lands resembling rice paddies
CHRYSAROBIN
− Is a mixture of neutral principles obtained from Goa powder
− Obtained in the lysogenous cavities in the wood of Andira
araroba
− Hot benzene is used to extract chrysarobin ( 50-70%) yields
from Goa powder
− A representative sample contains approximately 30- 40% of
chrysophenolanthrone or chrysophenolanthranol, 20%
emodinanthrone-monomethyl ether, and 30% of dehydro-
emodinanthrone- monomethyl ether
USE:
− Keratolytic - psoriasis, trichophytosis and chronic eczema.
− Itis very irritating to mucous membranes and should not be
used on the face or scalp.
DANTHRON or CHRYSARIN
− -1,8- DIHYDROXYANTHRAQUINONE