17H,21H,21bH,25H-21a,16a-(Iminomethano)-22,27a-methano-23H-diindolizino[6,7-a:7',6'-j]bispyrano[2',3':6,7]indolo[2,3-d:3',2'-g]carbazole-21,23,30,32-tetrone, 1,4,7c,11,15,15a,16,18,19,26,27,28,28a,29-tetradecahydro-1-hydroxy-4,4,11,11,15,15,29,29-octamethyl-, 14-oxide, (7cS,7dR,15aS,16aS,21aR,21bR,2...

Stephacidin B is a fungal metabolite that has been found in A. ochraceus.1 Dimeric stephacidin B is rapidly converted to a monomer, avrainvillamide , in vitro.2 Stephacidin B is cytotoxic to a variety of cancer cells, including testosterone-independent PC3 and -sensitive LNCaP prostate cancer cells (IC50s = 0.37 and 0.06 μM, respectively) and estradiol-independent SK-BR-3 and -sensitive MCF-7 breast cancer cells (IC50s = 0.32 and 0.27 μM, respectively).1 It induces apoptosis in HepG2 and Huh7 hepatocellular carcinoma cells when used at a concentration of 4 μM.3

1.Qian-Cutrone, J., Huang, S., Shu, Y.-Z., et al.Stephacidin A and B: Two structurally novel, selective inhibitors of the testosterone-dependent prostate LNCaP cellsJ. Am. Chem. Soc.124(49)14556-14557(2002) 2.Wulff, J.E., Herzon, S.B., Siegrist, R., et al.Evidence for the rapid conversion of stephacidin B into the electrophilic monomer avrainvillamide in cell cultureJ. Am. Chem. Soc.129(16)4898-4899(2007) 3.Hu, L., Zhang, T., Liu, D., et al.Notoamide-type alkaloid induced apoptosis and autophagy via a P38/JNK signaling pathway in hepatocellular carcinoma cellsRSC Adv.9(34)19855-19868(2019)