SYNTHETIC STUDIES ON SIALOGLYCOCONJUGATES .15. SYNTHESIS OF GANGLIOSIDE-GM3 ANALOGS CONTAINING A VARIETY OF LIPOPHILIC PARTS

Several ganglioside GM3 analogs, containing a variety of lipophilic parts in place of the ceramide moiety haVe been synthesized, Glycosylation of (2S,3R,4E)-2-azido-3-0-benzoyl-4-octa-decen-1,3-diol (2) with 0-(methyl 5-acetamido-4,7,8,9-tetra-0-acetvl-3,5-dideoxv-P -glycero- α-D -galacto- 2-nonulopyranosylonate)- (2→3)-(2,4-di-O-acetyl-6-O-benzoyl-β-D-galactopyranosyl)-(l→4)-3-0-acetyl-2,6-di-O-benzoyl-α-D-glucopyranosyl trichloroacetimidate (1.) gave the β-glycoside (5) which was converted, via selective reduction of the azide group, introduction of acyl groups, 0-deacylation, and de-esterification, into the desired compounds (10–12). On the other hand, coupling of 1 with 3-benzyloxycarbonyl-amino-1-propanol (3) or (2RS)-3-benzyloxycarbonylamino-2-0-benzoyl-1,2-propanediol (4) gave the corresponding β-glycosides 13 and 14 respectively. These were converted by N-debenzyloxycarbonylation coupling with 2-tetradecylhexadecanoic acid, 0-deacylation, and hydrolysis of the methyl ester group, into the end products (17 and 18). © 1990, Taylor & Francis Group, LLC. All rights reserved.