title: 4-Methylumbelliferyl 2-acetamido-2-deoxy-alpha-D-glucopyranoside, a fluorogenic substrate for N-acetyl-alpha-D-glucosaminidase.
abstract: Condensation of dimeric 3,4,6-tri-O-acetyl-2-deoxy-2-nitroso-alpha-D-glucopyranosyl chloride with 4-methylumbelliferone gave crystalline 4-methylumbelliferyl 3,4,6-tri-O-acetyl-2-deoxy-2-oximino-alpha-D-arabino-hexopyranoside. Acetylation of this adduct, reduction of the resulting crude O-acetyloxime with borane in oxolane, and acetylation gave the 3,4,6-tri-O-acetyl derivative of 4-methylumbelliferyl 2-acetamido-2-deoxy-alpha-D-glucopyranoside (1). A new sensitive assay of N-acetyl-alpha-D-glucosaminidase (EC 3.2.1.50) is made possible by fluorometric measurement of 4-methylumbelliferone liberated by enzymic hydrolysis of glycoside 1. Such assays are illustrated by results obtained with enzyme preparations from pig liver and human-blood serum.
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives*; D000118:Acetylglucosaminidase / Q000097:blood / Q000378:metabolism*; D000818:Animals; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D006596:Hexosaminidases / Q000378:metabolism*; D006801:Humans; D006923:Hymecromone / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D013552:Swine; D014468:Umbelliferones / Q000138:chemical synthesis*
chemical_list: D007202:Indicators and Reagents; D014468:Umbelliferones; C025158:4-methylumbelliferyl 2-acetamido-2-deoxy-beta-D-glucopyranoside; D006923:Hymecromone; D006596:Hexosaminidases; D000118:Acetylglucosaminidase; D005944:Glucosamine; D000117:Acetylglucosamine