Synthesis of novel 1-methyl-1H-pyridazino[3,4-b]indoles

Abstract New synthetic pathways have been elaborated to 1-methyl-1 H -pyridazino[3,4- b ]indoles starting from halopyridazin-3(2 H )-ones. Suzuki cross-coupling reaction of chloro, iodo, dichloro, and dibromo substituted pyridazin-3(2 H )-ones with 2-pivaloylaminophenylboronic acid followed by hydrolysis of the amide and subsequent ring closure via condensation gave fused indoles. Some of these compounds showed biological activity as antitrypanosomal agents.