Synthesis of an aryl 2-deoxy-β-glycosyl tetrasaccharide to probe retaining endo-glycosidase mechanism
摘要:
The synthesis of the 1,3-1,4-beta-glucanase substrate analogue 4-nitrophenyl O-beta-D-glucopyranosyl-(1 -> 4)-O-beta-D-glucopyranosyl-(1 -> 4)-O-beta-D-glucopyranosyl-(1 -> 3)-2-desoxi-beta-D-glucopyranoside 2 is reported. Starting from the main tetrasaccharide obtained by enzymatic depolymerization of barley beta-glucan, the synthetic scheme involves preparation of the Corresponding 3-O-substituted glycal which was converted into a 2-deoxy-alpha-glycosyl iodide as a glycosyl donor. The key glycosylation step was successfully achieved by nucleophilic substitution of the iodide donor with 4-nitrophenolate with high beta-selectivity. (C) 2009 Elsevier Ltd. All rights reserved.
Synthesis of an aryl 2-deoxy-β-glycosyl tetrasaccharide to probe retaining endo-glycosidase mechanism
摘要:
The synthesis of the 1,3-1,4-beta-glucanase substrate analogue 4-nitrophenyl O-beta-D-glucopyranosyl-(1 -> 4)-O-beta-D-glucopyranosyl-(1 -> 4)-O-beta-D-glucopyranosyl-(1 -> 3)-2-desoxi-beta-D-glucopyranoside 2 is reported. Starting from the main tetrasaccharide obtained by enzymatic depolymerization of barley beta-glucan, the synthetic scheme involves preparation of the Corresponding 3-O-substituted glycal which was converted into a 2-deoxy-alpha-glycosyl iodide as a glycosyl donor. The key glycosylation step was successfully achieved by nucleophilic substitution of the iodide donor with 4-nitrophenolate with high beta-selectivity. (C) 2009 Elsevier Ltd. All rights reserved.