CARBOHYDRATES CHAPTER 2 Flashcards
what do you mean by monosaccharide derivatives
monosaccharides each carry a number of -OH group to which substituents might be attached or could be replaced by other functional groups
examples of monosaccharides derivatives
1 acid n lactones
2 alditols
3 amino sugars
4 glycosides
how did acid and lactones formed?
Acid and lactones are formed through oxidation process.
example of acid and lactones
Mild oxidation of an aldose with alkaline Cu2+ (Fehling
solution) produces aldonic acids
what is alditols
Reduction of carbonyl group on a sugar produces the
class of polyhydroxy compounds called alditols.
examples of alditols
Important natural occuring alditols are erythritol, D-mannitol, D-glucitol (often called sorbitol)
what are amino sugars
- Two amino derivatives of simple
sugars are widely distributed in
natural polysaccharides named
glucosamine and galactosamine. - D-Glucosamine & D-Galactosamine
are simple amine sugars made by
replacing the hydroxyl at position two of glucose and galactose with an amine group
what are the further modifications of amino sugars?
glucosamine can be further modified to the following :
1 N-acetylglucosamine
2 muramic acid
3 N-acetylmuramic acid
when do glycosides are formed?
Glycosides are formed when elimination of water
between the anomeric hydroxyl of a cyclic monosaccharide and the hydroxyl group of another
compound yields O-glycosides.
what is the bond formed between glycosides called?
glycosidic bond
examples of glycosides
formation of Methyl-a-D-glucopyranoside
what are one of natural occurring glycosides
ouabain.
a toxin that inhibits the action of na+ and k+ ions across the plasma membrane
whats the other natural occurring glycosides
amygdalin.
a toxin that is found in seed of bitter almonds. this compound yields hydrogen cyanide.
