Chapter 25, Problem 25.9P

Interpretation Introduction

Interpretation:

In aldopentose, the carbon which determines the D and L configurations has to be determined.

Concept Introduction:

The D and L configurations can be defined by the $\text{–OH}$ group present on the penultimate carbon.  If the $\text{–OH}$ group is present on the right side of the carbon atom, it is said to be D-form (dextrorotatory form).  If the $\text{–OH}$ group is present on the left side of the carbon atom, it is said to be L-form (levorotatory form).