Studies on Aminosugars. XXIX. The Synthesis of 3′-O-Methylkanamycin

Abstract 6-O-(3-Amino-3-deoxy-α-d-glucopyranosyl)-2-deoxystreptamine, previously synthesized, was masked with ethoxycarbonyl, isopropylidene, and benzyl groups to give 6-O-(2-O-benzyl-3-deoxy-3-ethoxycarbonylamino-4,6-O-isopropylidene-α-d-glucopyranosyl)-N,N′-diethoxycarbonyl-2-deoxystreptaniine, which was condensed with 6-azido-2,4-di-O-benzyl-6-deoxy-3-O-methyl-α-d-glucopyranosyl chloride by a modified Koenigs-Knorr reaction to give a mixture of α,α- and α,β-diglycoside compounds. Hydrogenation of the azido group and removal of the masking groups gave a mixture of 3′-O-methylkanamycin and its diastereomer. The 3′-O-methylkanamycin was devoid of antibacterial activity.