Design and synthesis of novel cell wall inhibitors of Mycobacterium tuberculosis GlmM and GlmU

GlmM and GlmU are key enzymes in the biosynthesis of UDP-N-acetyl-D-glucosamine (UDP-GlcNAc), an essential precursor of peptidoglycan and the rhamnose-GlcNAc linker region in the mycobacterial cell wall. These enzymes are involved in the conversion of two important precursors of UDP-GlcNAc, glucosamine-6-phosphate (GlcN-6-P) and glucosamine-1-phosphate (GlcN-1-P). GlmM converts GlcN-6-P to GlcN-1-P, GlmU is a bifunctional enzyme, whereby GlmU converts GlcN-1-P to GlcNAc-1-P and then catalyzes the formation of UDP-GlcNAc from GlcNAc-1-P and uridine triphosphate. In the present study, methyl 2-amino-2-deoxyl-alpha-D-glucopyranoside 6-phosphate (1 alpha), methyl 2-amino-2deoxyl-beta-D-glucopyranoside 6-phosphate (1 beta), two analogs of GlcN-6-P, were synthesized as GlmM inhibitors; 2-azido-2-deoxy-alpha-D-glucopyranosyl phosphate (2) and 2-amino-2,3-dideoxy-3-fluoro-alpha-Dglucopyranosyl phosphate (3), analogs of GlcN-1-P, were synthesized firstly as GlmU inhibitors. Compounds 1 alpha, 1 beta, 2, and 3 as possible inhibitors of mycobacterial GlmM and GlmU are reported herein. Compound 3 showed promising inhibitory activities against GlmU, whereas 1 beta, 1 beta and 2 were inactive against GlmM and GlmU even at high concentrations. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.