AN APPROACH TO BRANCHED-CHAIN AMINO SUGARS, PARTICULARLY DERIVATIVES OF L-VANCOSAMINE (3-AMINO-2,3,6-TRIDEOXY-3-C-METHYL-L-lyxo-HEXOSE) ITS D ENANTIOMER, via THE CYANO-HYDRIN ROUTE

Article abstract of DOI:10.1016/0008-6215(82)84003-2

Methyl 4,6-O-benzylidene-2-deoxy-α-D-erythro-hexopyranosid-3-ulose reacted with potassium cyanide under equilibrating conditions to give, initially, methyl 4,6-O-bezylidene-3-C-cyano-2-deoxy-α-D-ribo-hexopyranoside (7), which, because it reverted slowly to the thermodynamically stable D-arabino isomer, could be crystallised directly from the reaction mixture.The mesylate derived from the kinetic product 7 could be converted by published procedures into methyl 3-acetamido-2,3,6-trideoxy-3-C-methyl-α-D-arabino-hexopyranoside, which was transformed into methyl N-acetyl-α-D-vancosamidine on inversion of the configuration at C-4.A hexopyranosid-3-ulose gave the kinetic cyanohydrin and thence, via the spiro-aziridine 27, methyl 3-acetamido-2,3,6-trideoxy-3-C-methyl-α-L-arabino-hexopyranoside, a known precursor of methyl N-acetyl-α-L-vancosaminide.