Synthetic studies on carbohydrate antibiotics. XIV. Syntheses of neamine and its diastereomer; the condensation of protected 2,6-diamino-2,6-dideoxy-.ALPHA.-D-glucopyranosyl bromide with a 2-deoxystreptamine derivative.

Abstract

3,4-Di-O-acetyl-2,6-dideoxy-2-(2′,4′-dinitroanilino)-6-phthalimido-α-d-glucopyranosyl bromide (I) was prepared in a good yield from glucosamine hydrochloride. A modified Konigs-Knorr condensation of this bromide with a 2-deoxysteptamine derivative afforded a neamine derivative (IX) and its diastereomer (X). These compounds, (IX) and (X), were identified by PMR spectroscopy after conversion into the corresponding N-acetyl derivatives, (XI) and (XII).