Synthesis of Precursors to L-Ristosamine and L-Daunosamine from L-Lactic Acid.

Abstract
Condensation of the protected L-lactaldehyde 4 with methyl 3-nitropropionate gave a mixture of nitro alcohols 5, which, in one step, was converted into a 2-5:1 mixture of nitro lactones 6 and 7. Hydrogenation, benzoylation and separation afforded the L-ristosamine precursor 8 and the L-daunosamine precursor 9.