As a part of our research concerning the design of analogs of natural compounds and evaluation of their antitumor activity, we decided to investigate the synthesis of new analogs of camptothecin. [ 8 8. Wall , ME ; Wani , MC ; Cook , CE ; Palmer , KE ; Mc Phail , AT ; Sim , GA Plant antitumor agents, I: Isolation and structure of camptothecin, a novel alkaloidal leukemia and tumor inhibitor from Camptotheca acuminata . J. Am. Chem. Soc. 1966 , 88 ( 16 ), ...