Reaction of 2-amino-2-deoxy-D-gluconic acid with hot acetic anhydride–sodium acetate

Abstract

Reinvestigation of the title reaction has shown that 2-acetamido-6-acetoxyhexa-2,4-dien-5-olide (1) and (Z)-and (E)-2-acetamido-6-acetoxyhexa-2,4-dien-4-olide [(2) and (3)] are produced in the proportions ca. 4 : 9 : 7, respectively. The recrystallised materials described in previous literature were not compound (1) as was thought but were in fact compound (2) or mixtures of (2) and (3); several consequential corrections to structures derived from the supposed (1) are required.