Cascade radical cyclization: Application in the development of new anticancer drug of camptothecin family and development of new synthetic method

This dissertation presents synthetic studies on new anticancer drug of camptothecin family and development of a new cascade radical reaction as a novel synthetic method. Camptothecin is a prominent lead for anticancer drug development. The synthetic studies on camptothecin include: semi-synthesis of silatecan and drug candidate DB-67 by silyl radical addition, synthesis of homosilatecans and asymmetric synthesis of homocamptothecins, total synthesis of novel E-ring analog, development of a palladium promoted cascade reaction of isonitrile and its application in synthesis of drug candidates DB-67 and DB-91. The last chapter describes the development of a new cascade radical cyclization reaction of thiocarbamates, thoamides and thiourea. The new radical reaction provides a novel approach to cyclopenta-fused quinoline structures such as furoquinolines and indoloquinolines.