On-line electrochemistry-bioaffinity screening with parallel HR-LC-MS for the generation and characterization of modified p38α kinase inhibitors

Anal Bioanal Chem. 2012 Apr;403(2):367-75. doi: 10.1007/s00216-011-5663-2. Epub 2012 Jan 8.

Abstract

In this study, an integrated approach is developed for the formation, identification and biological characterization of electrochemical conversion products of p38α mitogen-activated protein kinase inhibitors. This work demonstrates the hyphenation of an electrochemical reaction cell with a continuous-flow bioaffinity assay and parallel LC-HR-MS. Competition of the formed products with a tracer (SKF-86002) that shows fluorescence enhancement in the orthosteric binding site of the p38α kinase is the readout for bioaffinity. Parallel HR-MS(n) experiments provided information on the identity of binders and non-binders. Finally, the data produced with this on-line system were compared to electrochemical conversion products generated off-line. The electrochemical conversion of 1-{6-chloro-5-[(2R,5S)-4-(4-fluorobenzyl)-2,5-dimethylpiperazine-1-carbonyl]-3aH-indol-3-yl}-2-morpholinoethane-1,2-dione resulted in eight products, three of which showed bioaffinity in the continuous-flow p38α bioaffinity assay used. Electrochemical conversion of BIRB796 resulted, amongst others, in the formation of the reactive quinoneimine structure and its corresponding hydroquinone. Both products were detected in the p38α bioaffinity assay, which indicates binding to the p38α kinase.

Publication types

  • Evaluation Study

MeSH terms

  • Binding Sites
  • Chromatography, High Pressure Liquid / instrumentation
  • Chromatography, High Pressure Liquid / methods*
  • Drug Evaluation, Preclinical
  • Electrochemistry / instrumentation
  • Electrochemistry / methods*
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Kinetics
  • Mass Spectrometry / instrumentation
  • Mass Spectrometry / methods*
  • Mitogen-Activated Protein Kinase 14 / antagonists & inhibitors*
  • Mitogen-Activated Protein Kinase 14 / chemistry
  • Protein Binding

Substances

  • Enzyme Inhibitors
  • Mitogen-Activated Protein Kinase 14