Synthesis and biological evaluation of new homocamptothecin analogs.Eur J Med Chem. 2012 Aug; 54:281-6.EJ
In order to increase the stability of E-ring of homocamptothecins, the electron-withdrawing group -OH or -OAc was induced to α position of ring-E lactone. Ten new homocamptothecin analogs were synthesized. Most compounds showed potent in vitro anticancer activity and potent Topo I inhibition, which was equal or superior to that of CPT, SN-38 and 10-HCPT. The stability studies of this series also displayed significant improvement of the stability.