New Ferrocene Formates Bearing Isoxazole Moieties: Synthesis, Characterization, X-ray Crystallography, and Preliminarily Cytotoxicity against A549, HCT116, and MCF-7 Cell Lines

Abstract

Aims: To develop new anticancer agents based on ferrocene core. Background: Cancer has become the major cause of human death globally. The death caused by cancer mainly focuses on lung cancer, breast cancer, liver cancer, carcinoma of the colon, and rectum. Some small molecular inhibitors have been authorized by FDA for the treatment of cancer and several candidates are in different phases of clinical trials. However, cancer chemotherapy is still highly inadequate. Thus, it is indispensable to develop novel anticancer agents. Objective: Based on the previous good results, twelve novel structures of ferrocene formates bearing isoxazole moiety (3a-3l) were synthesized in this work for the development of anticancer agents. Methods: The target compounds were synthesized using Ferrocenecarboxylic acid and 3-[(R)-substitutedphenyl]- isoxazole-5-methanol catalyzed by DCC and DMAP. The structures of target compounds were characterized by 1H NMR, 13C NMR, MS, HR-MS and XRD. Then, their preliminarily in vitro cytotoxicity against A549, HCT116, and MCF-7 cell lines was evaluated using the MTT method. Results: The results showed that most compounds exhibited moderate cytotoxicity against A549, HCT116, and MCF-7 cell lines compared with the positive control gefitinib. However, (3b, 3c, 3e, 3j, and 3k) simultaneously exhibited stronger inhibitory activity against A549, HCT116, and MCF-7 cell lines, which can be regarded as promising metal-based lead compounds for the development of anticancer agents. Conclusion: In this work, twelve new structures of ferrocene derivatives containing isozaole moiety were synthesized and their cytotoxicity against 549, HCT116, and MCF-7 cell lines was evaluated. (3b, 3c, 3e, 3j, and 3k) simultaneously exhibited stronger inhibitory activity towards A549, HCT116, and MCF-7 cell lines, which can be regarded as promising metal-based lead compounds for the development of anticancer agents.