Chapter 23.3B, Problem 23.5P

Interpretation Introduction

Interpretation:

The configuration (R or S) that the bottom asymmetric carbon has for the D and L series of sugars is to be stated.

Concept introduction:

Rules for assigning R and S configuration are as follows:

• The groups are prioritized on the basis of their atomic numbers. Atom with highest atomic number is assigned the first position.
• If the atoms that are attached to the chiral centre are similar to each other, then the priority is given on the basis of the next atom attached.
• The molecule is oriented in such a manner that the lowest priority group comes at the dashed wedge.
• If the first three high priority groups are present in a clockwise manner then the molecule is assigned R configuration but if these are present in an anticlockwise manner then the molecule is assigned with S configuration.