[Synthetic studies of polyene macrolide antibiotics. 3. Hydrogenation of methyl-6-deoxy-2,3-O-isopropylidene-4-methylene- alpha-L-lyxo-hexopyranoside].

Experimental conditions of hydrogenation of the title compound are found (excess of Raney catalyst in benzene solution, 5 degrees C, 2h) to afford methyl 4,6-dideoxy-2,3-O-isopropylidene-4-C-methyl-alpha-L-mannopyranoside, the key intermediate in the synthesis of C33-C38 fragment of amphotericin B, with the yield as high as 57%.