Study On The Synthesis And Property Of The Derivates From Amino Acid

With the development of amino acids industry, researchers began to deeply process and exploit new product on the amino acids. Amino acids derivatives, of which the chemical synthesis has rapidly become a new research field in recent years, have been widely used at the aspect of agriculture, chemical industry, material, medical industry, food industry, and so on. So studing on the synthesis of amino acids derivatives is of a great significance both in theoretical and in practical side.Preparation technologies of cycloserine and L-carnosine were studied systematically in this paper. Intermediates and final products were characterized by melting point determination, IR and 1H-NMR. Accordingly, all of these lay a foundation on ulteriorly synthesizing the medicine intermediate, pesticide intermediate, and so on.Cycloserine was prepared from D-serine. D-serine was esterificated with methanol to synthesis D-serine methyl ester hydrochloride. Then this intermediate was chloridized with phosphorus pentachloride to synthesis D-2-amino-3-chloride propanic acid methyl ester hydrochloride, which was cyclized with hydroxylamine in the presence of alkali to give cycloserine. The conditions of esterification, chlorination and cyclization in each step of reaction were optimized. The total yield of cycloserine was 55%.Cycloserine was prepared from D-serine. Cycloserine was afforded through chlorination reaction, chloroformylation reaction and cyclized reaction. Comparing with the present technologies, this method can synchronously realize the chlorination and chloroformylation reaction of the D-Serine, and the reaction route was predigested. The conditions of chlorination, chloroformylation and cyclization in each step of reaction were optimized. The total yield of cycloserine was 50%.L-carnosine was produced byβ-alanine and L-histidine through the reactions of amido-protecting, chloroformylation, active-hydrogen-protecting, condensation and deprotection. The active-hydrogen-protecting of L-histidine used the trimethylchlorosilane. The effects of stuff molar ratio, reaction time, tempreture and solvent on the yield were studied. The total yield of L-carnosine was 88%.Hexamethyldisilazane was used as the protective agent for the active-hydrogenprotecting of L-histidine, and L-carnosine was produced byβ-alanine and L-histidine. Comparing with the present technologies, the active-hydrogen protective agent using in this technics has the same reactivity as the trimethylchlorosilane. However, the side effect of hexamethyldisilazane is much less and the price of it is much lower. What's more, the deprotection of the active-hydrogen-protecting is simple, and the yield of the protecting product is higher. So this route provides a high efficiency and low cost synthesis method for synthesizing higher yield and lower side effect product of L-carnosine.