[hahy-puh-zan-theen, -thin]
  1. a white, crystalline, almost water-soluble, alkaloidal purine derivative, C5H4N4O, found in animal and vegetable tissues: used chiefly in biochemical research.

Origin of hypoxanthine

First recorded in 1835–45; hypo- + xanthine
Related formshy·po·xan·thic, adjective

British Dictionary definitions for hypoxanthine


  1. a white or colourless crystalline compound that is a breakdown product of nucleoproteins. Formula: C 5 H 4 N 4 O

hypoxanthine in Medicine


  1. A purine present in muscle and other tissues, formed during uric acid synthesis.