Tri-O-benzoyl-β-L-rhamnopyranosyl and β-L-fucopyranosyl isothiocaynates. Partially protected β-L-rhamnopyranosylenamines

Article abstract of DOI:10.1016/0008-6215(93)84250-A

Regioselective benzoylations of N-(2,2-diethoxycarbonylvinyl)-β-L-rhamnopyranosylamine (1) yielded 2,3-di-O- (3), 3,4-di-O- (4), and 3-O-benzoyl-N-(2,2-diethoxycarbonylvinyl)-β-L-rhamnopyranosylamine (5) goether with the tri-O-benzoylated derivative 2. Syntheses of 2,3,4-tri-O-benzoyl-β-L-rhamno- (7) and -β-L-fuco-pyranosyl isothiocyanate (13) from 2 and L-fucopyranosylamine, respectively, are described. N-Phenacyl-N'-(2,3,4-tri-O-benzoyl-β-L-rhamno- (8) and -β-L-fuco-pyranosylthiourea (14) were prepared from 7 and 13, respectively, by reaction with phenacylamine. Conformational properties and MS data of the prepared compounds are discussed. Regioselective benzoylations of N-(2, 2-diethoxycarbonylvinyl)-B-L-rhamnopyranosylamine (1) yielded 2, 3-di-O- (3), 3,4-di-O- (4), and 3-O-benzoyl-N-(2, 2-diethoxycarbonylvinyl)-B-L-rhamnopyranosylamine (5) together with the tri-O-benzoylated derivative 2. Syntheses of 2,3, 4-tri-O-benzoyl-B-L-rhamno- (7) and -B-L-fuco-pyranosyl isothiocyanate (13) from 2 and L-fucopyranosylamine, respectively, are described. N-Phenacyl-N'-(2,3,4-tri-O-benzoyl-B-L-rhamno- (8) and -B-L-fuco-pyranosylthiourea (14) were prepared from 7 and 13, respectively, by reaction with phenacylamine. Conformational properties and MS data of the prepared compounds are discussed.