BIOC 2580 Lecture Notes - Lecture 13: Carbohydrate Chemistry, Heptose, Tetrose

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 2580
• Professor: John Dawson

Document Summary

Stereoisomers: monosaccharides contain asymmetric carbon atoms, all monosaccharides except dihydroxyacetone contain one or more chiral carbon atoms, gives rise to occurrence of optically active isomeric forms. Diastereomers some carbons different, some the same. Epimers one carbon different: a sugar with n chiral centres has 2n stereoisomers, every time a c atom is added, the number of isomers doubles. Hemiacetals and hemiketals: aldehydes and ketones can react with alcohols to produce hemiacetals and hemiketals, the original carbonyl carbon becomes chiral. If the oh of carbon 6 is nucleophile, then fructose will form a 6-membered pyranose ring. 13. 6: this chemical property provides a simple basis for detecting the presence and concentration of a sugar like glucose, **note: oxidation of sugars by cu2+ only occurs with the linear form. If an anomeric carbon is associated in a glycosidic bond, the sugar can no longer assume the linear form, and the sugar becomes non-reducing.