title: Preparation of 1,2-O-isopropylidene derivatives of alpha-D-galactoseptanose, beta-L-altroseptanose, and 3-O-methyl-alpha-D-guloseptanose.
abstract: Displacement of the tosyloxy group in 5-O-benzyl-1,2-O-isopropylidene-4-O-(p-toluenesulfonyl)-alpha-D-glucoseptanose has yielded derivatives of 1,2-O-isopropylidene-alpha-D-galactoseptanose. Acid catalysed acetonation then gave 1,2:3,4-di-O-isopropylidene-alpha-D-galactoseptanose or 1,2;4,5-di-O-isopropylidene-alpha-D-galactoseptanose using lower acid concentrations. Reduction of the ketone derived from 1,2:3,4-O-isopropylidene-alpha-D-septanose gave 1,2;3,4-di-O-isopropylidene-beta-L-altroseptanose. Reaction of 3,4-anhydro-5-O-benzyl-1,2-O-isopropylidene-alpha-D-galactoseptanose with sodium methoxide gave 5-O-benzyl-1,2-O-isopropylidene-4-O-methyl-alpha-D-glucoseptanose and 5-O-benzyl-1,2-O-isopropylidene-3-O-methyl-alpha-D-guloseptanose. Solution-state conformations of these compounds have been deduced from their 1H NMR spectra.
authors.affiliation: School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: G E
authors.initials: GE
authors.lastname: Driver
authors.forename: J D
authors.initials: JD
authors.lastname: Stevens
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D002236:Carbohydrate Conformation; D004187:Disaccharides / Q000138:chemical synthesis*; D005697:Galactosides / Q000138:chemical synthesis*; D006601:Hexoses / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D004187:Disaccharides; D005697:Galactosides; D006601:Hexoses; C057406:gulose; C013658:propylene