Design, synthesis and biological evaluation of 1, 4-dihydro indeno[1,2-c] pyrazole linked oxindole analogues as potential anticancer agents targeting tubulin and inducing p53 dependent apoptosis

Abstract A series of 1, 4-dihydroindeno-[1,2- c ] pyrazole linked oxindole conjugates have been synthesized by using Knoevenagel condensation method and further evaluated for their antiproliferative activity against HeLa, A549 and MDA-MB-231 human cancer cell lines along with HEK-293 (normal human embryonic kidney cells). Among the derivatives, compounds 12a, 12b , and 12d showed excellent cytotoxicity with IC 50 values ranging between 1.33 to 4.33  μM. Furthermore, detailed biological assays showed that there was accumulation of mitotic cells in G2/M phase, disruption of microtubule network and increase in the G2/M checkpoint proteins (Cyclin B1 and CDK1). Moreover, compound 12d with IC 50 value of 1.33  μM showed significant upregulation of tumor suppressor proteins like p53, p21 and pro-apoptotic Bax. The molecular docking analysis demonstrated that these congeners occupy the colchicine binding pocket of the tubulin.