Heteroleptic tri- and di-organotin(IV) carboxylates: Synthesis, characterization and anticancer evaluation

•Synthesized heteroleptic organotin(IV) complexes showed potent anticancer activity.•Complex 5 exhibited pentagonal bipyramidal geometry via single crystal XRD analysis.•DNA binding studies revealed groove binding and dual interaction modes with SS-DNA.•Anticancer complexes induced S phase arrest and apoptosis via intrinsic pathways. Herein heteroleptic tri- and di-butylorganotin(IV) carboxylate complexes with general formula R3SnL(N-N´)/R2SnL2(N-N´) have been synthesized using 3-methylbenzoic acid (L) as primary ligand and N-N´ donor heterocycles namely 2,2′-bipyridine (1 and 4), 1, 10-phenanthroline (2 and 5) and 2,9-dimethyl-1,10-phenanthroline (3 and 6) as hetero-ligands. The as-synthesized complexes were characterized by multitude spectroscopic techniques. Among the synthesized complexes, the complex 5 crystallized in triclinic crystal system and the single crystal analysis revealed that Sn(IV) center is seven coordinated resulting in a pentagonal bipyramidal geometry. The DNA binding affinity of the synthesized complexes was evaluated through UV–Visible spectroscopy, viscometry and theoretically through molecular docking. The results demonstrated that complexes possess high potential to bind with DNA through a spontaneous process. The complexes were tested for anticancer activities and were found to be potent having IC50 values comparable to standard drug Doxorubicin. Furthermore, potent complexes (2 and 6) caused an arrest in synthesis phase and activated intrinsic pathway of apoptosis in treated cancer cells.