Design, synthesis, and in vitro testing of alpha-methylacyl-CoA racemase inhibitors

J Med Chem. 2007 May 31;50(11):2700-7. doi: 10.1021/jm0702377. Epub 2007 May 4.

Abstract

The enzyme alpha-methylacyl-CoA racemase (AMACR) is overexpressed in prostate, colon, and other cancers and has been partially validated as a potential therapeutic target by siRNA knockdown of the AMACR gene. Analogs of the natural substrate branched chain alpha-methylacyl coenzyme A esters, possessing one or more beta-fluorine atoms, have been synthesized using Wittig, conjugate addition, and asymmetric aldol reactions and found to be reversible competitive inhibitors. Each diastereomer of the previously reported inhibitor ibuprofenoyl-CoA was also tested. The compounds had Ki values of 0.9-20 microM and are the most potent inhibitors yet known. The presence of beta-fluorine on the alpha-methyl group or the acyl chain results in a significant lowering of the Ki value compared with nonfluorinated analogs, and this is attributed to a lowering of the pKa of the alpha-proton, facilitating enolization and binding. Several of the CoA ester inhibitors were formed by incubating the free carboxylic acid precursors with cell free extracts and CoA. alpha-Trifluoromethyltetradecanoic acid, the precursor to the most potent inhibitor, was shown to inhibit growth of cancer cell lines PC3, CWR22 Rv1, and Du145 in a dose-dependent manner and could be related to the expression level of AMACR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyl Coenzyme A / chemical synthesis*
  • Acyl Coenzyme A / chemistry
  • Acyl Coenzyme A / pharmacology
  • Antineoplastic Agents / chemical synthesis*
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology
  • Binding Sites
  • Cell Proliferation / drug effects
  • Crystallography, X-Ray
  • Drug Design
  • Drug Screening Assays, Antitumor
  • Humans
  • Male
  • Myristates / chemical synthesis*
  • Myristates / chemistry
  • Myristates / pharmacology
  • Prostatic Neoplasms
  • Racemases and Epimerases / antagonists & inhibitors*
  • Racemases and Epimerases / chemistry
  • Stereoisomerism

Substances

  • Acyl Coenzyme A
  • Antineoplastic Agents
  • Myristates
  • alpha-trifluoromethyltetradecanoic acid
  • alpha-trifluoromethyltetradecanoyl-CoA
  • Racemases and Epimerases
  • alpha-methylacyl-CoA racemase