The shikimate pathway. Part I. Introduction; preparation of stereospecifically labelled 2-deuterio-derivatives of 3-dehydroquinic acid

Abstract

The 2ax-proton of 3-dehydroquinic acid is selectively exchanged for deuterium at pH 7·0 in deuterium oxide to give (2S)-2-deuterio-3-dehydroquinic acid (XIV)(0·65 atom deuterium). Structure (XIV) was proved by degradation to citric acid and equilibration with the enzyme aconitase. Catalytic deuteriogenolysis of (2R)-2-bromotriacetylquinide gave (2RS)-2-deuteriotriacetylquinide, which was converted into (2RS)-2-deuterio-3-dehydroquinic acid. Equilibration of the latter with water at pH 7·0 gave (2R)-2-deuterio-3-dehydroquinic acid (XXXIII)(0·70 atom deuterium).