Routes of Synthesis of Carbapenems for Optimizing Both the Inactivation of L,D-Transpeptidase LdtMt1 of Mycobacterium tuberculosis and the Stability toward Hydrolysis by β-Lactamase BlaC

J Med Chem. 2016 Apr 14;59(7):3427-38. doi: 10.1021/acs.jmedchem.6b00096. Epub 2016 Mar 18.

Abstract

Combinations of β-lactams of the carbapenem class, such as meropenem, with clavulanate, a β-lactamase inhibitor, are being evaluated for the treatment of drug-resistant tuberculosis. However, carbapenems approved for human use have never been optimized for inactivation of the unusual β-lactam targets of Mycobacterium tuberculosis or for escaping to hydrolysis by broad-spectrum β-lactamase BlaC. Here, we report three routes of synthesis for modification of the two side chains carried by the β-lactam and the five-membered rings of the carbapenem core. In particular, we show that the azide-alkyne Huisgen cycloaddition reaction catalyzed by copper(I) is fully compatible with the highly unstable β-lactam ring of carbapenems and that the triazole ring generated by this reaction is well tolerated for inactivation of the L,D-transpeptidase LdtMt1 target. Several of our new carbapenems are superior to meropenem both with respect to the efficiency of in vitro inactivation of LdtMt1 and reduced hydrolysis by BlaC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / antagonists & inhibitors
  • Bacterial Proteins / metabolism
  • Carbapenems / chemical synthesis*
  • Carbapenems / pharmacology*
  • Humans
  • Hydrolysis
  • Kinetics
  • Mycobacterium tuberculosis / drug effects
  • Mycobacterium tuberculosis / enzymology
  • Peptidyl Transferases / antagonists & inhibitors*
  • Peptidyl Transferases / metabolism
  • Tuberculosis / drug therapy
  • Tuberculosis / microbiology
  • beta-Lactamase Inhibitors / chemical synthesis
  • beta-Lactamase Inhibitors / pharmacology*
  • beta-Lactamases / metabolism*

Substances

  • Bacterial Proteins
  • Carbapenems
  • beta-Lactamase Inhibitors
  • Peptidyl Transferases
  • beta-Lactamases