Iodinated Mononuclear Iron Carbonyl Compounds And Its Application As Carbon Monoxide Releasing Molecule

Carbon monoxide（CO）is a kind of gas signal molecule,its concentration determines its effect.The higher the concentration of carbon monoxide,the lower the oxygen carrying capacity of hemoglobin.Carbon monoxide also acts as a messenger in the immune system,cardiovascular system and nervous system,and participates in angiogenesis,tumor growth and the carbon monoxide/heme oxygenase-1 system.In order to give full play to its medical value,carbon monoxide releasing molecules（CORMs）have been widely concerned,which can release co quantitatively under certain conditions.Iron is an essential element for human body,so iron carbonyl compounds have great application prospects.In this paper,a series of iron（II）carbonyl compounds were synthesized and characterized,and their release behavior and cytotoxicity were studied:The first part is the synthesis and CO release of iron carbonyl compounds containing phosphorus ligands.Through several bidentate phosphorus ligands（1,2-bis（diphenylphosphineyl）ethane,dppe;1,3-bis（diphenylphosphaneyl）propane,dppp;N-cyclohexyl-N-（diphenylphosphaneyl）-1,1-diphenylphosphanamine,PNP-Cy;）Three new iron carbonyl compounds（[Fe（CO）₂（dppe）I₂],1,[Fe（CO）₂（dppp）I₂],2;[Fe（CO）₂（PNP-Cy）I₂],3;）were obtained by the reaction of cis-[Fe（CO）₄I₂].Its structure was characterized by IR,UV-Vis,NMR and elemental analysis.The crystal structures of compounds 2 and 3 were determined by X-ray single crystal diffraction.The CO release behaviors of compounds 1-3 under red light monitored in DMSO was studied.its half-life is 17-55 min.Cytotoxicity evaluation showed that compounds 1 and 2 had low toxicity(IC₅₀>100?mol L^-（16）)to RT112 human bladder cancer cells,while compound 3 had high toxicity(IC₅₀=42?mol L^-（16）).The detection results of 3,3’,5,5’-tetramethylbenzidine（TMB）showed that these compounds did not produce iodine free radicals in solution.The second part is the synthesis,CO release and cytotoxicity of several carbonyl iron compounds.Several iron carbonyl compounds 4-8 were synthesized by the reaction of several alkyl amines and benzylamines.It was characterized by IR,UV-Vis and NMR.The infrared changes of iron carbonyl compounds with three and two carbonyl groups were studied by using infrared spectroscopy.It was found that iron carbonyl compounds with three carbonyl groups would transform into compound 5 after excessive propylamine.The CO release behaviors of compound 4-8 in DMSO was monitored by infrared spectroscopy.The release process of gas in the closed environment was studied by infrared spectroscopy.The oil-water partition coefficients of these compounds were measured by UV-Vis spectrophotometer.The results show that these compounds have strong fat solubility.The cytotoxicity test showed that compound 4-8 had low toxicity to RT112 human bladder cancer cells(IC₅₀>100μmolL^-1)...