ici-85966 ici-85966 ici-85966 (former tentative brand name stilbostat), also known as diethylstilbestrol (des) bis(di(2-chloroethyl)carbamate), is a synthetic, nonsteroidal estrogen and cytostatic antineoplastic agent of the stilbestrol group and a nitrogen mustard ester of diethylstilbestrol (des) which was developed for the treatment of breast cancer and prostate cancer but was never marketed (possibly due to the toxicity of des). ici-85966clinical dataother namesstilbostat; diethylstilbestrol (des) bis(di(2-chloroethyl)carbamate)identifiers iupac name phenyl]hex-3-en-3-yl]phenyl] n,n-bis(2-chloroethyl)carbamate cas number15470-58-3 ypubchem cid3037081chemspider2300916uniivud64clj7zchemical and physical dataformulac28h34cl4n2o4molar mass604.39 g·mol−13d model (jsmol)interactive image smiles cc/c(=c(/cc)\c1=cc=c(c=c1)oc(=o)n(cccl)cccl)/c2=cc=c(c=c2)oc(=o)n(cccl)cccl inchi inchi=1s/c28h34cl4n2o4/c1-3-25(21-5-9-23(10-6-21)37-27(35)33(17-13-29)18-14-30)26(4-2)22-7-11-24(12-8-22)38-28(36)34(19-15-31)20-16-32/h5-12h,3-4,13-20h2,1-2h3/b26-25+key:boizoyrdxiymcy-oceacifdsa-n