Synthesis And Characterization Of Cyclometallated...

In recent years, interest towards the development of cyclometallated organometallic ruthenacycles as anticancer drugs against several selective cancers has significantly increased. Herein, we report the synthesis and characterization of three new di-topic N,C-donor ligands based on a phenyl-benzimidazole core, and their corresponding doubly cyclometallated Ru(II)-functionalized ruthenacycles (1–3). All these six synthesized compounds were evaluated as anticancer drug against using selective cancer cell lines such as AGS (gastric carcinoma), SK-hep-1 (hepatocellular carcinoma), and HCT-15 (colorectal carcinoma) and compared to known anticancer drugs cisplatin, oxaliplatin, and doxorubicin along with the corresponding starting arene-ruthenium precursor (RuPD). Accordingly, two equivalents of phenyl-benzimidazole was reacted separately with corresponding aryl di-bromide in the presence of excess sodium hydride in dimethylformamide at room temperature, affording benzimidazole dito pic ligands as the colorless crystalline materials in good yield L1 (80%), L2 (82%), and L3 (87%) (Supporting Information, ESI). 1H-NMR resonance spectra show the formation of phenyl benzimidazolyl core containing ditopic ligands L1–L3. The high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) data of the ligands molecular ion peak observed at m/z 491.19 (L1), 491.17 (L2) and 491.23 (L3) clearly proved the formation of ligands (the ESI). Results and discussion RuPD was reacted