title: The analysis of agarose by the reductive cleavage method.
abstract: Agarose was structurally characterised by permethylation and subsequent reductive cleavage. Treatment of the fully methylated polysaccharide with triethylsilane and a mixture of trimethylsilyl methanesulfonate and boron trifluoride etherate followed by a newly developed, acid-catalysed, in situ acetylation yielded two main products: the expected 4-O-acetyl-1,5:3,6-dianhydro-2-O-methyl-L-galactitol and 3-O-acetyl-1,5-anhydro-2,4,6-tri-O-methyl-D-galactitol in the molar ratio 1:1, and traces of 1,5-anhydro-2,3,4,6-tetra-O-methyl-D-galactitol. Reductive cleavage using triethylsilane and trimethylsilyl trifluoromethanesulfonate as the catalyst yielded the same anhydroalditols as well as a smaller amount of 1,4,5-tri-O-acetyl-3,6-anhydro-2-O-methyl-L-galactitol due to ring-opening of 3,6-anhydrogalactopyranosyl residues during reductive cleavage. In this paper, results from reductive cleavage are compared with results using standard methylation analysis.
authors.affiliation: Institut für Biochemie und Lebensmittelchemie, Universität Hamburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Kiwitt-Haschemie
authors.forename: H
authors.initials: H
authors.lastname: Heims
authors.forename: H
authors.initials: H
authors.lastname: Steinhart
authors.forename: P
authors.initials: P
authors.lastname: Mischnick
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D005690:Galactose / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D012685:Sepharose / Q000737:chemistry*
chemical_list: D012685:Sepharose; D005690:Galactose