Synthesis of Novel 2-butyl-1H-benzo [4, 5] imidazo [1, 2-a] imidazo [4, 5-e] Pyridine-5-carbonitrile Derivatives and Evaluation of their Anticancer Activity ACHANTA VENKATA HANUMANTHA RAO, RAYAM PARSHARAMULU, MALTHUM SHANKARAIAH, VADALI LAKSHMAN RAO and ANIREDDY JAYA SHREE *

A series of new 2-butyl-1H-benzo[4,5]imidazo[1,2-a]imidazo[4,5-e]pyridine-5-carbonitrile derivatives were synthesized by the self cyclisation of (E)-2-(1H-benzo[d]imidazol-2-yl)-3-(2-butyl4-chloro-1H-imidazol-5-yl)acrylonitrile in the presence of piperidine as catalyst, which in turn were prepared by the condensation of substituted N-alkyl 2-butyl-4-chloro-1H-imidazole-5-carbaldehydes with 2-cyanomethylbenzimidazole in the presence of catalytic amount of L-proline in ethanol or by using piperidine as a base. Newly synthesized compounds which incorporate a variety of N-substituent moieties were characterized by spectral data and screened for anticancer activity against MCF-7 breast cancer cell line. The results showed that compounds 3b, 3a and 4b possess significant anti proliferative activity with IC50 values 26.59 and 27.98, 36.95 μM respectively.