Synthesis of a thio analogue of n-propyl kojibioside, a potential glucosidase inhibitor.
The disaccharide alpha-D-Glc p-(1-S-2)-beta-D-Glc p-(1-OPr) 1, a thio analogue of alpha-D-Glc p-(1 --> 2)-alpha-D-Glc p-(1-OPr)(n-propyl kojibioside) in which the inter-glycosidic oxygen atom is replaced by sulfur, has been synthesized for evaluation as a potential glucosidase inhibitor. Glycosylation of the 2-thiol glucopyranosyl acceptor 4 with the trichloroacetimidate of 2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranose 5 gave the alpha-linked disaccharide 6 stereoselectively. Deprotection was performed by hydrogenolysis in the presence of Pd/C to give 1 as the beta-n-propyl glycoside. Glycosylation of the thiol 4 with the trichloroacetimidate of 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranose 8 gave a 1:2.3 mixture if the alpha and beta disaccharides (9 and 10); evidence is presented for the occurrence of the orthoester 11, as an intermediate in the formation of the beta-disaccharide.
Andrews
J S
JS
Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada.
Pinto
B M
BM
D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D005959:Glucosidases / Q000037:antagonists & inhibitors*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D013237:Stereoisomerism; D013455:Sulfur; D013863:Thioglucosides / Q000138:chemical synthesis* / Q000737:chemistry
D004187:Disaccharides; D013863:Thioglucosides; C094902:allyl 2-O-(2,3,4,6-tetra-O-acetylglucopyranosyl)-3,4,6-tri-O-benzyl-2-thioglucopyranoside; D013455:Sulfur; C008237:kojibiose; D005959:Glucosidases