rubitecan rubitecan rubitecan (inn, marketing name orathecin) is an oral topoisomerase inhibitor, developed by supergen (now astex pharmaceuticals, inc.; a member of the otsuka group). rubitecanclinical datatrade namesorathecinother names9-nitrocamptothecin9-nc9-nitro-20(s)-camptothecincamptogen(19s)-19-ethyl-19-hydroxy-10-nitro-17-oxa-3,13-diazapentacyclohenicosa-1(21),2,4,6,8,10,15(20)-heptaene-14,18-dioneroutes ofadministrationoral (capsules)atc codenonelegal statuslegal status application withdrawn pharmacokinetic databioavailability25–30% (rubitecan and 9-ac; in dogs)protein binding97% (rubitecan), 65% (9-ac)metabolismprobably cyp-dependentmetabolites9-aminocamptothecin (9-ac)elimination half-life15–18 hours (rubitecan), 18–22 hours (9-ac)excretionbile and feces (major proportion), urine (the minor one)identifiers iupac name (4s)-4-ethyl-4-hydroxy-11-nitro-1h-pyranoindolizinoquinoline-3,14(4h,12h)-dione cas number91421-42-0 ypubchem cid472335chemspider414807 nuniih19c446xxbkeggd04031 nchebichebi:90225 nchemblchembl77305 ncomptox dashboard (epa)dtxsid7046752 chemical and physical dataformulac20h15n3o6molar mass393.355 g·mol−13d model (jsmol)interactive image smiles cc1(c2=c(coc1=o)c(=o)n3cc4=cc5=c(c=cc=c5(=o))n=c4c3=c2)o inchi inchi=1s/c20h15n3o6/c1-2-20(26)13-7-16-17-10(8-22(16)18(24)12(13)9-29-19(20)25)6-11-14(21-17)4-3-5-15(11)23(27)28/h3-7,26h,2,8-9h2,1h3/t20-/m0/s1 nkey:vhxnkpbccmumsw-fqevstjzsa-n n ny (what is this?) (verify) history on january 27, 2004, supergen announced that it has completed the submission of an nda for rubitecan to the us fda, and was accepted for filing in march 2004. in january 2005, and under the direction of then-ceo james manuso, supergen withdrew the nda for rubitecan, based on feedback indicating that the current data package would not be sufficient to gain us approval, and in january 2006, the marketing authorization application (maa) filed with the european medicines agency (ema) was also withdrawn. the name rubitecan is a portmanteau of supergen's founder, dr. joseph rubinfeld, and the chemical name 9-nitrocamptothecin. synthesis large scale production of rubitecan has encountered problems. the direct nitration of camptothecin results in regioselectivity problems. one way that has been used to synthesize rubitecan is to nitrate 10-hydroxycamptothecin then remove the hydroxyl functional group. use as anti-cancer drug rubitecan is a compound used extensively in cancer research. rubitecan is an effective drug against pancreatic cancer and other solid tumors. one major problem is the lack of oral bioavailability due to low permeability and poor water solubility. one study shows 9-nc-sd through soluplus1-based solid dispersion system is a much more effective delivery method than free 9-nc.