4-Hydroxymandelic acid


4-Hydroxymandelic acid is a chemical compound used to synthesize atenolol. The compound typically occurs as a monohydrate.

Synthesis and occurrence

It is produced from 4-hydroxypyruvic acid by the action of the enzyme -p-hydroxymandelate synthase:
4-Hydroxymandelic acid can be synthesized by the condensation reaction of phenol and glyoxylic acid: