O-Perbenzoylated 5-(beta-D-glucopyranosyl)tetrazole was reacted with N-benzyl carboximidoyl chlorides to give the corresponding 4-benzyl-3-(beta-D-glucopyranosyl)-5-substituted-1,2,4-triazoles. Removal of the O-benzoyl and N-benzyl protecting groups by base catalysed transesterification and catalytic hydrogenation, respectively, furnished a series of 3-(beta-D-glucopyranosyl)-5-substituted-1,2,4-triazoles with aliphatic, mono- and bicyclic aromatic, and heterocyclic substituents in the 5-position. Enzyme kinetic studies revealed these compounds to inhibit rabbit muscle glycogen phosphorylase b: best inhibitors were the 5-(4-aminophenyl)- (K-i 0.67 mu M) and the 5-(2-naphthyl)-substituted (K-i 0.41 mu M) derivatives. This study uncovered the C-glucopyranosyl-1,2,4-triazoles as a novel skeleton for nanomolar inhibition of glycogen phosphorylase. (C) 2014 Elsevier Masson SAS. All rights reserved.
[EN] GLYCOGEN PHOSPHORYLASE INHIBITORS<br/>[FR] INHIBITEURS DE PHOSPHORYLASE DE GLYCOGÈNE