What is the maximum number of stereo isomers that can be written for aldo-pentose?

1 Answer
Nov 12, 2015

There are eight possible stereoisomers of the aldopentoses.

Explanation:

The general structure of an aldopentose is

www.chem.ucla.edu

We see that the molecule has three chiral carbons.

The maximum number of stereoisomers is #2^n#, where #n# is the number of chiral carbons.

Since #n = 3# and #2^3 =8#, there are eight possible aldopentoses.

Here are the structures of four of the aldopentoses.

www2.chemistry.msu.edu

The other stereoisomers are the four L-aldopentoses: the mirror images of the D-aldopentoses shown above.