Selective targeting of the HIV-1 reverse transcriptase catalytic complex through interaction with the "primer grip" region by pyrrolobenzoxazepinone non-nucleoside inhibitors correlates with increased activity towards drug-resistant mutants

Biochem Pharmacol. 2008 Jul 15;76(2):156-68. doi: 10.1016/j.bcp.2008.04.009. Epub 2008 Apr 29.


PBO (pyrrolobenzoxazepinone) derivatives are non-nucleoside reverse transcriptase inhibitors (NNRTIs), which display a selective interaction with the catalytic ternary complex of HIV-1 reverse transcriptase (RT) and its substrates. In order to develop novel PBOs with improved resistance profiles, we synthesised additional PBO derivatives, specifically designed to target highly conserved residues in the beta12-beta13 hairpin, the so-called "primer grip" region of HIV-1 RT. Here, we investigated the biochemical and enzymological mechanism of inhibition of HIV-1 RT wild type and carrying NNRTIs-resistance mutations, by these derivatives. Our kinetic analysis indicates that the ability of PBOs to selectively target the catalytic ternary complex of RT with its substrates directly correlates with greatly reduced sensitivity to NNRTIs-resistance mutations, particularly the K103N substitution. Molecular modeling and docking studies provided an explanation for this correlation at the structural level.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Alkynes
  • Animals
  • Azepines / chemical synthesis
  • Azepines / pharmacology*
  • Benzoxazines / pharmacology
  • Catalysis
  • Cell Line
  • Cells, Cultured
  • Cyclopropanes
  • DNA-Directed DNA Polymerase / metabolism
  • Drug Resistance, Viral*
  • HIV Reverse Transcriptase / antagonists & inhibitors*
  • HIV-1 / genetics
  • Humans
  • Leukocytes, Mononuclear / drug effects
  • Mice
  • Models, Molecular
  • Mutation
  • Nevirapine / pharmacology
  • Reverse Transcriptase Inhibitors / chemical synthesis
  • Reverse Transcriptase Inhibitors / pharmacology*


  • Alkynes
  • Azepines
  • Benzoxazines
  • Cyclopropanes
  • Reverse Transcriptase Inhibitors
  • Nevirapine
  • reverse transcriptase, Human immunodeficiency virus 1
  • HIV Reverse Transcriptase
  • DNA-Directed DNA Polymerase
  • efavirenz