The project will be directed toward the synthesis of benzo[1,2-b:3,4-b'] dipyrrole derivatives. These materials have become of interest because of the discovery of an antibiotic with anti-tumor activity (CC-1065 NCS 298223) which is constructed from three substituted benzo[1,2-:3,4-b'] dipyrrole rings. Four general approaches to benzo[1,2-b:2,4-b'] dipyrrole systems are outlined. These include direct synthesis using methodology adapted from indole chemistry, synthesis by dimerization of pyrroles, synthesis by cyclization-aromatization and synthesis by sulfide extrusion. Specific starting materials and procedures are discussed for each of the synthetic approaches. Methods for coupling the three subunits of the CC-1065 structure by formation of amide bonds are indicated. The generalization of the synthetic method to analogs of CC-1065 is discussed. Specific analogs designed to probe the role of certain structural elements are presented. These particularly emphasize the possible role of the cyclopropane ring in the mechanism of action of CC-1065. The synthetic materials will be evaluated for antineoplastic activity in collaboration with the Drug Development Branch, Division of Cancer Treatment, National Institutes of Health.
