Syntheses, Cytotoxicity and Properties of CO Releasing Molecules Containing Acetyl Salicylamide‐3‐pyridine

Abstract A series of CO‐releasing molecules [M(CO)5L] (M=Cr, W, Mo, L=acetyl salicylamide 3‐pyridine, 1–3; L=N,N‐dimethyl‐4‐pyridine, 4–6; L=nicotinamide, 7–9; L=4‐CHO‐pyridine, 10–12) were synthesized. And in this paper, we have investigated mainly cytotoxicity and properties of the CO‐releasing molecules containing acetyl salicyamide‐3‐pyridine, namely complexes 1–3. The stability of complexes 1 and 2 was evaluated by means of UV‐Vis spectroscopy and 1H NMR spectra. The results indicate complexes 1 and 2 were stable in methanol and acidic aqueous solution, but unstable and decayed in basic media (pH 10.0). Among all the complexes, complex 2 was the slowest CO‐releaser, and its half‐life was 73.8 min. Complex 9 containing nicotinamide was the fastest CO‐releaser with half‐life only 6.5 min. In addition, cytotoxic effects of all the complexes on the proliferation of fibroblast line were assayed by MTT. Among all the complexes, the IC50 of complex 1 was 6 µmol/L, revealing complex 1 possessed stronger antiproliferative activity than the control. Analysis by Flow cytometry revealed that complex 1 arrested Hela cells in S phase while complexes 2 and 8 arrested in G2/M phase. Cell apoptosis caused by the complexes mainly occurred in "Late apoptosis".