Selective N-deacetylation of p-nitrophenyl N,N′-diacetyl-β-chitobioside and its use to differentiate the action of two types of chitinases

We report the synthesis of a novel compound for chitinase assays, p-nitrophenyl 2-acetamido-4-O-(2-amino-2-deoxy-β-d-glucopyranosyl)-2-deoxy-β-d-glucopyranoside [GlcNGlcNAc-pNP] by selective N-deacetylation of p-nitrophenyl 2-acetamido-4-O-(2-acetamido-2-deoxy-β-d-glucopyranosyl)-2-deoxy-β-d-glucopyranoside [(GlcNAc)2-pNP] using a purified chitin deacetylase isolated from Colletotrichum lindemuthianum ATCC 56676. FABMS, 1H NMR, and 13C NMR analyses confirmed the structure of this new compound. This disaccharide derivative can be used to distinguish special chitinases that effectively remove partially deacetylated parts of substrates within a mixture of chitinases which degrades (GlcNAc)2-pNP.