Synthesis of Imidazo[1,2-c]pyrazolo [4,3-e]pyrimidines Derived From Indole and Related Heterocycles

The syntheses of the title heterocycles were achieved using 5-amino-1-(1-benzyl-1H-indol-3-ylcarbonyl)-1H-pyrazole-4-carbonitrile as starting material. These compounds were converted into the 4-imidazolinyl derivatives which were subjected to cyclization reactions to afford the title compounds.