CAS 210357-38-3: 2H-1-Benzopyran-2-one, 7-[[2-(acetylamino)-2-deoxy-6-O-sulfo-β-D-glucopyranosyl]oxy]-4-methyl-, monopotassium salt

4-Methylumbelliferyl 2-acetamido-2-deoxy-beta-D-glucopyranoside-6-sulfate potassium salt is a fluorogenic substrate for beta-N-acetylglucosaminidase. After enzymatic cleaveage, free 4-methylumbelliferone (also known as hymecromone) is released, exhibiting blue fluorescence upon excitation with UV light. The strongest fluorescence of 4-methylumbelliferone requires deprotonation of the hydroxyl group (thus requires alkaline pH), with a maximal fluorescence intensity obtained with excitation at 350 to 370 nm and emission at 440 to 470 nm. The use of 4-methylumbelliferyl 2-acetamido-2-deoxy-beta-D-glucopyranoside-6-sulfate potassium saltas a substrate for measuring the beta-N-acetylglucosaminidase activity is used for diagnosis of Mucopolysaccharidosis IIIB (MPS IIIB) (a rare lysosomal storage disorder) and Sanfilippo B syndrome screening.