28. Carbohydrates

(c) How many asymmetric carbons and stereoisomers are there for an aldohexose? For a ketohexose?

How many stereoisomers are possible for

c. a ketotriose?

Answer the following questions about the eight aldopentoses:

a. Which are enantiomers?

b. Which are C-2 epimers?

A student isolated a monosaccharide and determined that it had a molecular weight of 150. Much to his surprise, he found that it was not optically active.

What is the structure of the monosaccharide?

Draw the mechanism for the hydroxide ion–catalyzed cleavage of fructose-1,6-bisphosphate.