Synthesis and anticancer activity of oxindole derived imidazo[1,5-a]pyrazines.

A series of oxindole derivatives of imidazo[1,5-a]pyrazines were prepared and confirmed by 1H NMR, mass and HRMS data. These compounds were evaluated for their anticancer activity against a panel of 52 human tumor cell lines derived from nine different cancer types: leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate and breast. Among them compound 7l showed significant anticancer activity with GI50 values ranging from 1.54 to 13.0 μM. Cell cycle arrest was observed in G0/G1 phase upon treatment of A549 cells with 6.5 μM (IC50) concentration of compound 7l and induced apoptosis. This was confirmed by Annexin V-FITC as well as DNA fragmentation analysis and interestingly this compound (7l) did not affect the normal cells.