Syntheses of O-protected 2-amino-2-deoxy-gentiobioside hydrohalides

Article abstract of DOI:10.1016/S0040-4020(01)87962-X

The syntheses of ethyl 3,4-di-O-acyl(benzyl)-2-benzyloxycarbonylamino-2-deoxy-6-O-trityl-α-D -glucopyranosides (2-4) and methyl 3,4-di-O-acyl(benzyl)-2-deoxy-2-[(2',2'-dimethoxycarbonylvinyl)amino]- 6-O-trityl-]-α-D-glucopyranosides (12-14) are reported. The partially protected D-glucosamine derivatives ethyl 3,4-di-O-benzyl- (5) and 3-benzyl-2-benzyloxycarbonylamino-2-deoxy-α-D-glucopyranoside (6), ethyl 3,4-di-O-benzoyl-2-benzyloxycarbonylamino-2-deoxy-α-D-glucopyranoside (9), methyl 3,4-di-O-acyl(benzyl)-2-deoxy-2-dimethoxycarbonylvinylamino-α-D-gluco pyranosides (15-17) have been prepared or isolated as by-products. The preparation of ethyl 3,4-di-O-acetyl- (18), 3,4-di-O-benzoyl- (19), and 3,4-di-O-benzyl-2-benzyloxycarbonylamino-2-deoxy-6-O-(2,3,4,6-tetra-O- acetyl-β-D-glucopyranosyl)-α-D-glucopyranosides (20), and methyl 3,4-di-O-acetyl- (21), 3,4-di-O-benzoyl- (22), and 3,4-di-O-benzyl-2-deoxy-2-dimethoxycarbonylamino-6-O-(2,3,4,6-tetra-O- acetyl-β-D-glucopyranosyl)-α-D-glucopyranosides (23) through glycosylation reactions using 2, 3, 4, 12, 13, and 14 resepctively as glycosyl acceptors and acetobromoglucose as glycosyl donor is described. The N-protecting group of 18, 19, and 21 was removed to give the alkyl hexa-O-acyl-2-amino-2-deoxy gentiobioside hydrohalides 24-26 respectively.