title: Glycosidase-catalyzed deoxy oligosaccharide synthesis. Practical synthesis of monodeoxy analogs of ethyl beta-thioisomaltoside using Aspergillus niger alpha-glucosidase.
abstract: Enzymatic transglycosylation using four possible monodeoxy analogs of p-nitrophenyl alpha-D-glucopyranoside (Glc alpha-O-pNP), modified at the C-2, C-3, C-4, and C-6 positions (2D-, 3D-, 4D-, and 6D-Glc alpha-O-pNP, respectively), as glycosyl donors and six equivalents of ethyl beta-D-thioglucopyranoside (Glc beta-S-Et) as a glycosyl acceptor, to yield the monodeoxy derivatives of glucooligosaccharides were done. The reaction was catalyzed using purified Aspergillus niger alpha-glucosidase in a mixture of 50 mM sodium acetate buffer (pH 4.0)/CH3CN (1:1 v/v) at 37 degrees C. High activity of the enzyme was observed in the reaction between 2D-Glc alpha-O-pNP and Glc beta-S-Et to afford the monodeoxy analogs of ethyl beta-thiomaltoside and ethyl beta-thioisomaltoside that contain a 2-deoxy alpha-D-glucopyranose moiety at their glycon portions, namely ethyl 2-deoxy-alpha-D-arabino-hexopyranosyl-(1,4)-beta-D-thioglucopyranoside and ethyl 2-deoxy-alpha-D-arabino-hexopyranosyl-(1,6)-beta-D-thioglucopyranoside, in 6.72% and 46.6% isolated yields (based on 2D-Glc alpha-O-pNP), respectively. Moreover, from 3D-Glc alpha-O-pNP and Glc beta-S-Et, the enzyme also catalyzed the synthesis of the 3-deoxy analog of ethyl beta-thioisomaltoside that was modified at the glycon alpha-D-glucopyranose moiety, namely ethyl 3-deoxy-alpha-D-ribo-hexopyranosyl-(1,6)-beta-D-thioglucopyranoside, in 23.0% isolated yield (based on 3D-Glc alpha-O-pNP). Products were not obtained from the enzymatic reactions between 4D- or 6D-Glc alpha-O-pNP and Glc beta-S-Et.
authors.affiliation: Laboratory of Bio-organic Chemistry, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa-shi, Kanagawa 252-8510, Japan. nishio@brs.nihon-u.ac.jp
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nishio
authors.forename: Chika
authors.initials: C
authors.lastname: Kanai
authors.forename: Wataru
authors.initials: W
authors.lastname: Hakamata
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ogawa
authors.forename: Kousuke
authors.initials: K
authors.lastname: Nakajima
authors.forename: Shigeki
authors.initials: S
authors.lastname: Hoshino
authors.forename: Akari
authors.initials: A
authors.lastname: Matsuishi
authors.forename: Ryu
authors.initials: R
authors.lastname: Kawachi
authors.forename: Tadatake
authors.initials: T
authors.lastname: Oku
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D006031:Glycosylation; D006868:Hydrolysis; D007534:Isomaltose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000096:biosynthesis* / Q000302:isolation & purification; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013863:Thioglucosides / Q000138:chemical synthesis* / Q000737:chemistry; D000520:alpha-Glucosidases / Q000378:metabolism*
chemical_list: D009844:Oligosaccharides; D013863:Thioglucosides; D007534:Isomaltose; D000520:alpha-Glucosidases