title: Molecular and crystal structures of two 1,6-anhydro-beta-maltotriose derivatives.
abstract: Crystal structures of two 1,6-anhydro-beta-maltotriose derivatives, 1,6-anhydro-beta-maltotriose nonaacetate and 6"-bromo-6"-deoxy-1,6-anhydro-beta-maltotriose octaacetate, have been determined. Both structures are isomorphous and belong to the orthorhombic system, space group of P2(1)2(1)2(1), with cell dimensions of a = 15.659(3) A, b = 20.587(6) A, c = 13.023(2) A and a = 15.402(7) A, b = 19.737(8) A, c = 13.481(5) A, respectively. Each molecule has three alpha-(1-->4)-linked glucose units, and two of them have a typical 4C1 chair conformation, while the glucose unit with the 1,6-anhydro bridge has a 1C4 chair-envelope intermediate conformation. In spite of introducing the 1,6-anhydro bridge and acetyl groups, the conformations of the glycosidic linkages in these molecules are almost the same as those of other alpha-(1-->4)-linked oligosaccharides. Crystal structures are stabilized by hydrophobic interactions and by a weak intermolecular hydrogen bond of C-H. . .O.
authors.affiliation: Faculty of Technology, Tokyo University of Agriculture and Technology, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kamitori
authors.forename: K
authors.initials: K
authors.lastname: Itazu
authors.forename: K
authors.initials: K
authors.lastname: Noguchi
authors.forename: K
authors.initials: K
authors.lastname: Okuyama
authors.forename: S
authors.initials: S
authors.lastname: Kitamura
authors.forename: K
authors.initials: K
authors.lastname: Takeo
authors.forename: S
authors.initials: S
authors.lastname: Ohno
mesh_terms: D000085:Acetates / Q000737:chemistry; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D018360:Crystallography, X-Ray; D005947:Glucose / Q000737:chemistry; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D014312:Trisaccharides / Q000737:chemistry*
chemical_list: C098289:1,6-anhydro-beta-maltotriose nonaacetate; C098290:6''-bromo-6''-deoxy-1,6-dianhydro-beta-maltotriose octaacetate; D000085:Acetates; D014312:Trisaccharides; C008317:maltotriose; D005947:Glucose