Nano ZnO catalyzed green synthesis and cytotoxic assay of pyridinyl and pyrimidinyl bisphosphonates

A straight forward approach ensuring the anchoring of bisphosphonate moiety onto various pyridinyl and pyrimidinyl amines is described by the three-component reaction of an amine, diethyl phosphite, and triethyl orthoformate in the presence of catalytic amount of nano ZnO as an environmentally benign and heterogeneous catalyst under solvent-free microwave irradiation conditions. All the synthesized compounds are evaluated for anti-cell proliferation activity against human breast (MCF-7), prostate (DU-145), osteosarcoma (MG-63), fibrosarcoma (HT-1080), multiple myeloma (RPMI-8226) cancer cell lines using sulforhodamine-B (SRB) assay method, and adriamycin as a reference drug. All the title compounds showed promising cytotoxic activity on the five cell lines. One compound was two times more active than adriamycin on all the five cancer cell lines. Graphical abstract