New Route to Branched-chain Aminodeoxy Sugars by Reaction of Ketoses with Acetonitrile. Synthesis of Methyl 3-C-2′-Aminoethyl-2-deoxy-α-D-arabino-hexopyranoside

Addition of methyl 4,6-O-benzylidene-2-deoxy-α- D -erythro-hexopyranosid-3-ulose ( 1 ) to acetonitrile in liquid ammonia at −50 to −60° in the presence of lithium amide gave, in high yield, crystalline methyl 4,6-O-benzylidene-3-C-cyanomethyl-2-deoxy-α- D -arabino-hexopyranoside ( 2 ) exclusively. The proof of structure 2 is described. Debenzylidenation of 2 afforded the branched-chain cyano glycoside 3 . Compound 3 was converted into its 3,4,6-tri-O-acetate ( 8 ) and 4,6-di-O-p-nitrobenzoate ( 9 ) derivatives. Catalytic hydrogenation of 3 over rhodium on alumina yielded methyl 3-C-2′-aminoethyl-2-deoxy-α- D -arabino-hexopyranoside which was characterized as its N-2,4-dinitrophenyl derivative ( 7 ).