title: Sulfated and pyruvylated disaccharide alditols obtained from a red seaweed galactan: ESIMS and NMR approaches.
abstract: The water-soluble acid agaran isolated from Acanthophora spicifera (Rhodophyta) was submitted to alkaline treatment for the complete cyclization of alpha-L-Galp 6-sulfate to 3,6-An-alpha-L-Galp units. The modified agaran was then partially depolymerized using partial reductive hydrolysis. The resulting oligosaccharide mixture was fractionated by adsorption and ion-exchange chromatography. Fractions were purified by gel-filtration chromatography and studied by ESIMS and NMR spectroscopy, including 1D 1H, 13C, DEPT and 2D 1H, 1H COSY, TOCSY and 1H, 13C HMQC procedures. The following neutral, pyruvylated, sulfated and sulfated/pyruvylated disaccharide alditols were obtained: beta-D-Galp-(1-->4)-3,6-An-L-GalOH; 4,6-O-(1-carboxyethylidene)-beta-D-Galp-(1-->4)-3,6-An-L-GalOH; beta-D-Galp 2-sulfate-(1-->4)-3,6-An-L-GalOH and 4,6-O-(1-carboxyethylidene)-beta-D-Galp 2-sulfate-(1-->4)-3,6-An-L-GalOH.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, PO Box 19046, Curitiba, Brazil.
authors.forename: Alan G
authors.initials: AG
authors.lastname: Gonçalves
authors.forename: Diogo R B
authors.initials: DR
authors.lastname: Ducatti
authors.forename: M Eugênia R
authors.initials: ME
authors.lastname: Duarte
authors.forename: Miguel D
authors.initials: MD
authors.lastname: Noseda
mesh_terms: D002845:Chromatography; D003500:Cyclization; D004187:Disaccharides / Q000032:analysis / Q000302:isolation & purification*; D005685:Galactans / Q000032:analysis / Q000737:chemistry*; D005690:Galactose / Q000031:analogs & derivatives*; D006868:Hydrolysis; D019906:Nuclear Magnetic Resonance, Biomolecular; D009844:Oligosaccharides / Q000032:analysis / Q000302:isolation & purification; D011773:Pyruvates; D000461:Rhodophyta / Q000737:chemistry*; D012624:Seaweed / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013402:Sugar Alcohols / Q000032:analysis / Q000302:isolation & purification*; D013463:Sulfuric Acid Esters
chemical_list: D004187:Disaccharides; D005685:Galactans; D009844:Oligosaccharides; D011773:Pyruvates; D013402:Sugar Alcohols; D013463:Sulfuric Acid Esters; C086947:galactose 6-sulfate; D005690:Galactose