Terminal Modified 2-Chloro-4-nitrophenyl β-D-Maltotetraosides as Substrates for a Human α-Amylase Assay

Abstract

Eight novel 2-chloro-4-nitrophenyl maltotetraosides modified at the 6⁴- and/or 4⁴-position were synthesized for human pancreatic and salivary α-amylase substrates. In these compounds, 2-chloro-4-nitrophenyl O-[4, 6-di-O-(N-isopropyl)carbamoyl-α-D-glucopyranosyl]-(1→4)-bis[O-α-D-glucopyranosyl-(1→4)]-β-D-glucopyranoside (9) was rapidly hydrolyzed by the two amylases at a limited position to produce 2-chloro-4-nitrophenyl β-D-glucopyranoside. Taking advantage of the properties, 9 was found to be a good substrate for a human α-amylase assay using only β-glucosidase as a coupled enzyme.