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.


The general structure of an aldopentose is


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.


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