Rational design, synthesis and in vitro evaluation of novel exo-methylene butyrolactone salicyloylamide as NF-κB inhibitor

Abstract (−)-Dehydroxymethylepoxyquinomicin ((−)-DHMEQ, 1 ) is a specific inhibitor of NF-κB. It binds to SH group in the specific cysteine residue of NF-κB components with its epoxide moiety to inhibit DNA binding. In the present research, we have designed and synthesized an epoxide-free analog called ( S )-β-salicyloylamino-α-exo-methylene-ƴ-butyrolactone (SEMBL, 3 ). SEMBL inhibited DNA binding of NF-κB component p65 in vitro . It inhibited LPS-induced NF-κB activation, iNOS expression, and inflammatory cytokine secretions. It also inhibited NF-κB and cellular invasion in ovarian carcinoma ES-2 cells. Moreover, its stability in aqueous solution was greatly enhanced compared with (−)-DHMEQ. Thus, SEMBL has a potential to be a candidate for a new anti-inflammatory and anticancer agent.