Synthesis, Characterization and Anticancer Activity of a New Cinnamyl-Substituted Benzimidazolium Salt and Its Silver(I)–NHC Complex

Abstract

Silver–NHC (Ag–NHC) complexes have gained considerable attention in recent years due to their significant catalytic activities and promising biological properties. Moreover, their effectiveness as carbene transfer agents in the preparation of other metal–NHC complexes has further increased their importance in coordination chemistry. In this study, a novel benzimidazolium salt bearing a cinnamyl substituent was synthesized by the reaction of N-alkylbenzimidazole with 2-methylbenzyl chloride. The Ag(I)-NHC complex was successfully synthesized by DCM interaction of the benzimidazolium salt with silver oxide. The structural characterization of the obtained compounds was carried out using 1H and 13C NMR spectroscopy, FT-IR spectroscopy, and LC-HRMS techniques. Furthermore, the synthesized benzimidazolium salt 1 and Ag(I)-NHC complex 2 were evaluated for their anticancer activity against the A 549 cancer cell line using an in vitro approach. Moreover, when tested in vitro, these compounds showed significant activity against the tested cancer cell line compared to cisplatin; in particular, complex 2 showed quite significant anticancer activity.