title: Synthesis of a trehalose homolog, 6-deoxy-alpha-D-gluco-heptopyranosyl 6-deoxy-alpha-D-gluco-heptopyranoside, and the corresponding bis(heptosiduronic acid).
abstract: Crystalline 6-deoxy-alpha-D-gluco-heptopyranosyl 6-deoxy-alpha-D-gluco- heptopyranoside (8) and (6-deoxy-alpha-D-gluco-heptopyranosyluronic acid) 6-deoxy-alpha-D-gluco-heptopyranosiduronic acid (7) were synthesized from alpha, alpha-trehalose (1). Reaction of 2,3,4,2',3',4'-hexa-O-acetyl- 6,6'-di-O-tosyl-alpha, alpha-trehalose with sodium dicarbonylcyclopentadienyliron, followed by oxidative hydrolysis or methanolysis, gave the 2,3,4,2',3',4'-hexa-acetate of 7 or its dimethyl ester, respectively. O-Deacetylation (Zemplén) then gave 7 and its dimethyl ester. Reduction of the hexa-O-acetyldicarboxylic acid with borane-oxolane complex yielded 8. Alternatively, cyanide displacement of hexa-O-acetyl-alpha, alpha-trehalose 6,6'-ditriflate gave the dinitrile hexa-acetate of 7, which was O-deacetylated and then hydrolyzed with alkaline hydrogen peroxide to yield 7. 2,3,4,2',3',4'-Hexa-O-benzyl-alpha, alpha-trehalose 6,6'-ditriflate was similarly converted into the dinitrile, which was hydrolyzed to the corresponding diamide. Treatment of the 2,3,4,2',3',4'-hexa- O-acetyl-alpha, alpha-trehalosuronic acid 16 with thionyl chloride followed by diazomethane gave a crystalline bisdiazoketone which, however, failed to produce the expected bis(heptosiduronic acid) on attempted Wolff rearrangement.
authors.affiliation: Department of Chemistry, University of Ottawa, Ontario, Canada.
authors.forename: H H
authors.initials: HH
authors.lastname: Baer
authors.forename: R L
authors.initials: RL
authors.lastname: Breton
authors.forename: Y P
authors.initials: YP
authors.lastname: Shen
mesh_terms: D000107:Acetylation; D055598:Chemical Phenomena; D002621:Chemistry; D004187:Disaccharides / Q000138:chemical synthesis*; D006868:Hydrolysis; D013400:Sugar Acids; D014199:Trehalose
chemical_list: D004187:Disaccharides; D013400:Sugar Acids; C065009:6-deoxy-gluco-heptopyranosyl 6-deoxy-gluco-heptopyranoside; C065010:6-deoxy-alpha-gluco-pyranosiduronic acid; D014199:Trehalose