Synthesis of p-trifluoroacetamidophenyl (4,6-dideoxy-4-formamido-3-C-methyl-2-O-methyl-alpha-L-mannopyranosyl)- (1-->3)-(2-O-methyl-alpha-D-rhamnopyranosyl)-(1-->3)- (2-O-methyl-alpha-L-fucopyranosyl)-(1-->3)-(alpha-L-rhamnopyranosyl)- (1-->2)-6-deoxy-alpha-L-talopyranoside: a spacer-armed pentasaccharide glycopeptidolipid antigen of Mycobacterium avium serovar 14.
Syntheses of p-trifluoroacetamidophenyl glycosides of the haptenic pentasaccharide and the non-reducing disaccharide unit of the title pentasaccharide are reported. The synthesis of the terminal N-formylkansosamine unit started from methyl 6-deoxy-2,3-O-isopropylidene-alpha-L-lyxo- hexopyran-4-uloside which, after C-3 methylation, was transformed into a glycosyl donor [3-O-benzyl-4-N-benzylformamido-4,6-dideoxy-3-C-methyl-2-O-methyl- alpha,beta-L-mannopyranosyl trichloroacetimidate (20), and used for the synthesis of p-trifluoroacetamidophenyl (4-formamido-4,6-dideoxy-3-C-methyl-2-O-methyl-alpha-L-mannopyranosyl)- (1-->3)-6-deoxy-2-O-methyl-alpha-D-mannopyranoside (29). Ethyl (3-O-benzyl-4-N-benzylformamido-4,6-dideoxy-3-C-methyl-2-O-methyl- alpha-L-mannopyranosyl)-(1-->3)-4-O-benzyl-6-deoxy-2-O-methyl-1-thio- alpha-D-mannopyranoside (31), prepared by glycosylation of ethyl 4-O-benzyl-6-deoxy-2-O-methyl-1-thio-alpha-D-mannopyranoside with 20, served as glycosyl donor in a 2 + 3 block synthesis of the title pentasaccharide.
Bajza
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Research Group for Carbohydrates of the Hungarian Academy of Sciences, Debrecen, Hungary.
Kövér
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KE
Lipták
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D000942:Antigens, Bacterial / Q000737:chemistry*; D002240:Carbohydrate Sequence; D006020:Glycopeptides / Q000737:chemistry / Q000276:immunology; D006241:Haptens; D008969:Molecular Sequence Data; D015269:Mycobacterium avium Complex / Q000737:chemistry* / Q000276:immunology; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000276:immunology; D011510:Proteolipids / Q000737:chemistry / Q000276:immunology
C114827:4-trifluoroacetamidophenyl 4,6-dideoxy-4-formamido-3-C-methyl-2-O-methylmannopyranosyl-1-3-(2-O-methylrhamnopyranosyl)-1-3-(2-O-methylfucopyranosyl)-1-3-rhamnopyranosyl-(1-2)-6-deoxytalopyranoside; D000942:Antigens, Bacterial; D006020:Glycopeptides; D006241:Haptens; D009844:Oligosaccharides; D011510:Proteolipids