SEARCH

User ID: 999999
Version: 4.37.48

www.memory.com
You are in browse mode. You must login to use MEMORY

   Log in to start

level: Level 1 of GLYCOSIDES

Questions and Answers List

CLASSIFICATION PART

level questions: Level 1 of GLYCOSIDES

QuestionAnswer
an organic compound, usually of plant or animal origin, which on enzymatic or acid hydrolysis gives one or more sugar moieties along with non-sugar moiety.glycoside
two parts of glycosides1 Glycone (sugar portion) 2 Aglycone/Genin (Non sugar portion)
1 the active part of glycoside. 2 __ helps in the solubilization of __, for increasing the __ of the drug.1 Aglycone/Genin (Non sugar portion) 2 Sugar, non-sugar, bioavailability
the most frequently occurring sugar portion is __ although __ and other sugars are the components of glycosides.1 B-D-glucose 2 rhamnose, digitoxose, cymarose
1 Linkage between sugar and non-sugar portion is usually called a __ 2 The term 'glycoside' is a very general one which embraces all the many and varied combinations of sugars and aglycones. True or False1 Glycosidic linkage 2 True
More precise terms of a glycoside are available to describe particular classes. Some of these terms refer to: 1 The sugar part of the molecule example: __ 2 The aglycone part examples: __ 3 the physical or pharmacological property examples: __1 glucoside 2 anthraquinone 3 saponin “soap-like”, cardiac “having an action on the heart”).
1 As there exist an ether linkage between the sugar and non-sugar component, glycosides may be considered as __ 2 Chemically, GLYCOSIDES are __ 3 Many important drugs are glycosides and their pharmacological effects are largely determined by the structure of the __1 sugar ether 2 Acetals 3 aglycone.
1 The most important cleavage enzymes are the __ 2 the most important synthetic enzymes in nature are __1 glycoside hydrolases 2 glycosyltransferases
Glycone characteristics1 It consist of a single sugar group – monosaccharides- glucose, rhamnose Or several sugar groups - oligosaccharides 2 Crystalline or amorphous 3 Soluble in water 4 Soluble in alcohol 5 Insoluble in organic solvents like benzene, ether
Aglycone characteristics1 Soluble in organic solvents like benzene, ether 2 Hydrolysed by water, enzymes, mineral acids 3 Normally aromatic in nature known as the aromatic aglycone or the genin portion 4 Optically active
It is often very difficult to isolate intact glycosides because of their __polar character.
Classification of glycoside is by1 Glycone 2 Type of glycosidal linkage 3 Aglycone
By glycone classification 1 If the glycone group of a glycoside is glucose, then the molecule is a __ 2 if it is fructose, then the molecule is a __ 3 Modern system of naming glycosides using the termination __ 4 if it is glucuronic acid, then the molecule is a __1 Glucoside 2 Fructoside 3 '-oside' (e.g. sennoside). 4 glucuronide,
In the body, toxic substances are often bonded to __ to increase their water solubility; the resulting __ are then excreted.glucuronic acid, glucuronides
1 Has glucose as the sugar component 2 Has a sugar such as arabinose 3 Contains rhamnose 4 Contains both rhamnose and glucose1 Glucoside 2 Pentoside 3 Rhamnosides 4 Rhamnoglucosides
By type of glycosidic bond glycosides are classified as __ or __ depending on whether the glycosidic bond lies "above" or "below" the plane of the cyclic sugar molecule.α-glycosides or β-glycosides.
1 The usual linkage between the sugar and the aglycone is the __ 2 Most numerous kind of glycoside found in nature1 Oxygen linkage 2 O-glycoside
Other glycosidal formations1 O-glycoside (Oxygen) 2 S-glycoside (Sulphur) 3 N-glycoside (Nitrogen)