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Four stereoisomers of 6-amino-6-deoxyheptonic acid, having the l-glycero-d-galacto (1), d-glycero-d-galacto (2), l-glycero-d-gluco (3), and d-glycero-d-gluco (4) configurations, were synthesized from d-galacto- (8) and d-gluco-dialdose (23) derivatives, respectively. Cyanomesylation of 8 and 23 gave two C-6 epimers, respectively, which were separately converted, via the corresponding 6,7-epimino derivatives, into 6-(benzyloxycarbonyl)amino-6-deoxy derivatives by reduction with lithium aluminum hydride, N-(benzyloxycarbonyl)ation, and acetolysis with acetic acid. After deprotection of each hemiacetal, the stereoisomers were oxidized with bromine, followed by total deprotection, to give 1–4. Among these products, 1 and 3 proved to be identical with the naturally occurring destomic and epi-destomic acid obtained from antibiotic destomycins.