Discovery of small molecule fusion inhibitors targeting HIV-1 gp41

Gp41 is regarded as an attractive target for development of HIV-1 entry inhibitors since it mediates the fusion process of HIV- 1 entry into the target cell through the six-helix bundle (6-HB) formation between its N-heptad repeat (NHR) and C-heptad repeat (CHR). Any chemical entity that disrupts the six-helix bundle formation may inhibit the fusion process, thereby blocking HIV-1 entry into the target cells. A brief review of discovering small molecule inhibitors targeting gp41 is presented here, including the development of assay methods, current known small molecule inhibitors and their binding mode studies. Lessons learned and challenges remained in view of blocking protein-protein interaction between NHR and CHR are also discussed.