Discovery of trans-3-(pyridin-3-yl)acrylamide-derived sulfamides as potent nicotinamide phosphoribosyltransferase (NAMPT) inhibitors for the potential treatment of cancer.

Nicotinamide phosphoribosyltransferase (NAMPT) has emerged as a promising target for the discovery of anticancer drugs. Based on NAMPT inhibitor FK866 that has been advanced into phase II trial, we identified a trans-3-(pyridin-3-yl)acrylamide compound 13 incorporating with a biarylsulfanilamide moiety as a new NAMPT inhibitor. Further structure-activity relationship (SAR) exploration led to additional biarylsulfanilamide-derived compounds with high in vitro NAMPT inhibitory potency and antiproliferative activity. In particular, compound 23, the most potent NAMPT inhibitor (IC50 = 5.08 nM), showed single-digit nanomolar antiproliferative activity against DU145, Hela, and H1975 cells with IC50 values of 2.90 nM, 2.34 nM, and 2.24 nM, respectively, and even subnanomolar level against K562, MCF-7, and HUH7 cells with IC50 values of 0.46 nM, 0.23 nM and 0.53 nM, respectively. Our findings provided promising lead compounds for the discovery of more potent NAMPT inhibitors as anticancer drugs.