10H-1,3-Dioxolo(4,5-g)pyrano(3',4':6,7)indolizino(1,2-b)quinoline-8,11(7H,13H)-dione, 7,14-diethyl-7-hydroxy-, (7S)- 169900-78-1 7-Ethyl-10,11-methylenedioxy-20-S-camptothecin