The Synthesis, Characterization And Slow-release Mechanism Of Fischer Carbene Water-soluble Carbon Monoxide Releasing Molecules

The challenge for the synthesis of water-soluble transition metal carbonyl carbon monoxide-releasing molecules?CORMs?is how to incorporate hydrophilic organic units into the carbonyl metal nucleus to construct biocompatible therapeutic carbon monoxide releasing molecules.In this paper,a novel method for the coupling of amino and metal carbonyl compounds was developed by using Cr?CO?₅L as a precursor,and a series of Fischer carbene water-soluble molecules?Fc-CORMs?were synthesized.In this paper,27 novel CORMs were obtained and characterized by comprehensive spectroscopy.The structure of compound 4a was analyzed by X-ray diffraction.Myoglobin experiments show that most of the compounds can hydrolyze and release CO.Light interpretation experiments revealed that Fc-CORM 5a can target myoglobin to release five molecules of CO.Cell tests showed that the compounds are basically nontoxic and have certain anticancer activity.The work of this thesis mainly includes the following five parts:1.The coupling reaction between amino and Fischer carbene was developed.Fourteen amino acids,6-Aminocaproic acid,and 5-Aminovaleric acid were selected.Three types of Fischer carbene water-soluble molecules?la-16a?were designed and synthesized.On this basis,in order to further improve the water solubility of Fc-CORM,a Cr?CO?₅L Fischer carbene amino acid sodium salt?lb-5b?and a polyethylene glycol monomethyl ether modified Cr?CO?₅L Fischer carbene compound?lc-6c?were prepared.Compounds were characterized by comprehensive spectroscopy,including FT-IR,¹H NMR,¹³C NMR,LC-MS,elemental analysis,and UV.The structures of the compounds were in agreement with expectations.In addition,the single crystal structure of Fc-CORM 4a was analyzed to determine the molecular stereo configuration of 4a.2.The aqueous solubility of amino acid carbene Fc-CORMs was systematically studied.The oil-water partition coefficient of 1a-16a,lb-5b was measured by the shake flask method,and the hydrophobicity of the two types of released molecules was evaluated comprehensively;the solubility of the compound was judged by turbidity with 1 mg of lc-6c dissolved in ultrapure water.The experimental results show that the logP of la-16a is between 0.29-2.27.The corresponding sodium salt lb-5b compound is one in which la,3a,4a,5a and 10a are prepared into the corresponding sodium salt logP between-0.15-0.73.Dissolution experiments found that pegylated lc-6c also has good water solubility.3.The sustained-release performance of Fc-CORMs under simulated in vitro conditions was measured using the myoglobin method.Amino-containing carbene Fc-CORM?la-16a?can hydrolyze release CO,and the half-life of 60?M Fc-CORM is 8min-33.8min;CO release of Fc-CORM can also control light intensity And time can be precisely adjusted to achieve a phased release of CO.60?M?carbene salt 2b-5b?can also hydrolyze and release CO,releasing 20.7-35.2?M of CO.lc-6c is more stable under physiological conditions,and has potential as a kind of light-excited CO-sensitive release molecule.4.The cytotoxicity of Fc-CORMs was evaluated by MTT assay.Biological activity experiments showed that the half-inhibitory concentration of RAW264.7 for 5a was 389.052?M/L.223.823?M/L 5a can kill 50%of rectal cancer cell DLD and 224.353?M/L 8a can kill 50%of rectal cancer cell DLD.344.864?M/L 5a can kill 50%gastric cancer cells MNK-45,298.379?M/L 8a can kill 50%gastric cancer cells MNK-45.These experiments demonstrate that Fc-CORMs have low biological toxicity and certain anticancer activity.5.The photolysis and hydrolys is process of Fc-CORMs was studied in detail.The photolysis process of the 5a compound was followed using IR,NMR,and mass spectrometry,and the intermediates of the hydrolysis process were followed using mass spectrometry.The mechanism study showed that the coordinated carbonyl CO of Fc-CORM dissociated one by one during the photolysis process,releasing CO,while the hydrolysis of carbene carbon was not observed during the hydrolysis.The release process may be CO dissociation,and H₂O goes right.The carbonyl substitution process ultimately results in the formation of lower carbonyl chromium fragment units and amino acid fragments.