Chapter 25.4, Problem 3P

Interpretation Introduction

Interpretation:

The absolute configurations of $\text{L-glycerol-3-phosphate}$ and naturally occurring $\text{phosphatidic acid}$ is to be determined.

Concept introduction:

The Cahn-Ingold-Prelog rule system ranks the substituents in the chirality center in the order of decreasing atomic number. The higher atomic number takes precedence over the lower atomic number for the substituent.

If the sequence of decreasing priority traces a clockwise path, then the configuration is R, and if it traces a counterclockwise path, the configuration is S.

Triacylglycerols can be produced by reactions of glycerols with acyl coenzyme A molecules.

Two acyl coenzyme A molecules add two acyl groups to the $\text{L-glycerol-3-phosphate}$ to yield $\text{phosphatidic acid}$ in the first step.