Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA
Guy Caljon
Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1 (S7), B-2610 Wilrijk, Belgium
Hélène Munier-Lehmann
Unit of Chemistry and Biocatalysis, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3523, 28 Rue du Dr. Roux, CEDEX 15 75724 Paris, France
Helena I. M. Boshoff
Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA
A series of Mycobacterium tuberculosis TMPK (MtbTMPK) inhibitors based on a reported compound 3 were synthesized and evaluated for their capacity to inhibit MtbTMPK catalytic activity and the growth of a virulent M. tuberculosis strain (H37Rv). Modifications of the scaffold of 3 failed to afford substantial improvements in MtbTMPK inhibitory activity and antimycobacterial activity. Optimization of the substitution pattern of the D ring of 3 resulted in compound 21j with improved MtbTMPK inhibitory potency (three-fold) and H37Rv growth inhibitory activity (two-fold). Moving the 3-chloro substituent of 21j to the para-position afforded isomer 21h, which, despite a 10-fold increase in IC50-value, displayed promising whole cell activity (minimum inhibitory concentration (MIC) = 12.5 μM).