10H-1,3-Dioxolo[4,5-g]pyrano[3',4':6,7]indolizino[1,2-b]quinoline-8,11(7H,13H)-dione, 15-chloro-7-ethyl-7-hydroxy-, (7S)- 9-Chloro-10,11-methylenedioxy-20(S)-CPT AIDS-058630 AIDS058630 Camptothecin analog NSC673591