Pyrazine based Pt(II) bis‐alkynyl organometallic complexes: Synthesis, characterization, and cytotoxic effect on A549 human lung carcinoma cells

A facile and efficient synthesis of a series of five new pyrazine‐based organometallic complexes is being reported. The complexes (2–6) have been fully characterized. Molecules 2, 3 and 6 were structurally characterized by single crystal X‐ray crystallographic analyses. Additionally, anticancer properties of these organometallic complexes have been studied against A549 human lung carcinoma cells. Biological studies suggest that complex 5 (with pendant pyridine moieties) exhibited maximal growth inhibitory cytotoxic effect even at lower concentration (nearly 0.5–1 μM) whereas the other four compounds (2, 3, 4 and 6) were non‐toxic below 1 μM concentration. Two complexes (4 and 6) were effective only at higher doses (approx 30 μM) while the remaining two organometallic complexes (2 and 3) were able to inhibit 50% cell growth at slightly lower concentration (nearly 10 μM). As far as IC50 is concerned, 5 exhibited a minimum value ranging between 3–5 μM which is comparable with cisplatin under similar conditions.