All About 3,4,6-Tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucosyl Trichloroacetimidate

Abstract

Treatment of 1,3,4,6-tetra-O-acetyl-2-(o-carboxybenzoylamino )-2-deoxy-β-D-glucose with ethyl chloroformate , followed by workup and treatment with methanol, did not give 1,3,4,6-tetra O-acetyl-2-deoxy-2-phthalimido-β-D-glucose as reported in the literature, but rather the methyl ester 1,3,4,6-tetra-O-acetyl-2-deoxy-2-(o- methoxycarbonylbenzoylamino )-β-D-glucose. The formation of this methyl ester is believed to proceed via 1,3,4,6-tetra-O-acetyl-2-deoxy-2- [(3′-oxo-1′,3′-dihydroisobenzofuran-1′-ylidene)amino]-β-D-glucose which was also formed from the amido carboxylic acid by treatment with dicyclohexylcarbodiimide . Optimal procedures are given for the preparation of the title compound 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucosyl trichloroacetimidate.