Chemical modification of some methyl (3,4-di-O-acetyl-2-deoxy-2-hydroxyimino-α-d-arabino-hexopyranosid)uronates
摘要:
Methyl [ethyl 3,4-di-O-acetyl-2-deoxy-2-(Z)-hydroxyimino-alpha-D-arabino-hexopyranosid]uronate (1) and N-tert-butoxycarbonyl-O-[methyl 3,4-di-O-acetyl-2-deoxy-2-(Z)-hydroxyimino-alpha-D-arabino-hexo-pyranosyluronate]-L-serine methyl ester (2) were modified at C-2 and C-3. They have been transformed into the corresponding methyl (2,3,4-tri-O-acetyl-alpha-D-glycopyranosid)uronates by the sequence of reactions 2-C=N-OH --> 2-C=O --> 2-C-OH --> 2-C-OAc. Reaction of 1 and 2 with sodium azide gave the corresponding methyl [ethyl 4-O-acelyl-3-azido-2,3-dideoxy-2-(Z)-hydroxyimino-alpha-D-glycopyranosid]uronates and N-tert-butoxycarbonyl- O-[methyl 4-O-acetyl-3-azido-2,3-dideoxy-2-(Z)-hydroxyimino-alpha-D-glycopyranosyluronate]-L-serine methyl esters. (C) 1997 Elsevier Science Ltd.