34 results about "P-hydroxyphenylglycine methyl ester" patented technology

The invention discloses a preparation method of D-4-hydroxy-phenylglycinate and hydrochloride thereof. D-4-hydroxyphenylglycine is used as an initial raw material. The methyl D-4-hydroxy-phenylglycinate or the hydrochloride thereof is prepared by reacting the D-4-hydroxyphenylglycine with methanol or a methanol solution of hydrogen chloride under the existence of trimethylchlorosilane and by post-treatment. The preparation method has characteristics of easily available raw materials, simple operation, high yield, high product purity and little environment pollution, and is suitable for industrial production.

The present invention relates to the field of compound synthesis and discloses a method for synthesizing D-para-hydroxyphenylglycine methyl ester. The method comprises the steps of: (1) in the presence of thionyl chloride, carrying out an esterification reaction of D-para-hydroxyphenylglycine resolving agent salt and methanol to obtain a D-para-hydroxyphenylglycine methyl ester resolving agent salt; (2) dropwise adding the D-para-hydroxyphenylglycine methyl ester resolving agent salt and an alkaline metal hydroxide to an aqueous D-para-hydroxyphenylglycine methyl ester solution at 10-15°C, controlling the pH value of the system at 6.5-7 during the dropwise addition, after completing the dropwise addition of the D-para-hydroxyphenylglycine methyl ester resolving agent salt, continuing the dropwise addition of the alkaline metal hydroxide until the pH value of the system is 7.5-8, then growing crystals under the conditions of a temperature of 10-15°C and the pH value of 7.5-8, and subsequently filtering the resultant crystallization liquid to obtain D-para-hydroxyphenylglycine methyl ester crystals and a mother liquor. With the adoption of the method provided by the present invention, D-para-hydroxyphenylglycine methyl ester can be produced with a higher yield.

The invention relates to a method for synthesizing cefprozil through an enzymatic method. According to the method, a cefprozil parent nucleus, D-para hydroxybenzene glycine methyl ester and / or D-para hydroxybenzene glycine ethyl ester, water and penicillin acylase react at the temperature of 10 DEG C-25 DEG C to obtain a crude cefprozil product and enzyme reaction mother liquor, the temperature is controlled to be 0 DEG C-15 DEG C, a pH value is controlled to be 0.2-0.8, N,N-dimethyl formamide is added, the mixture is stirred uniformly, a seed crystal is added for crystal growing, the pH value is adjusted to be 5.5-6.5, and the temperature is controlled to be 10 DEG C-30 DEG C to obtain a cefprozil N,N-dimethyl formamide compound; the temperature is controlled to be 0 DEG C-25 DEG C, water and the cefprozil N,N-dimethyl formamide compound are added into a reactor, the mixture is stirred for crystal transformation for 1-4.5 h, and then filtering, washing, swabbing-off and drying are carried out to obtain a finished cefprozil product. The cefprozil is high in product yield and high in purity, appearance is white, the preparing method is simple and easy to implement, the condition is mild, and the method is more suitable for industrial production.

The invention relates to a preparation method for a crystal of L-p-hydroxyphenylglycine methyl ester. The preparation method comprises the following steps: (1) adding L-p-hydroxyphenylglycine methyl ester hydrochloride into a container filled with water, keeping solid-liquid ratio of solution within 0.08-0.15g / ml, stirring and dissolving under constant temperature at 25-40 DEG C, continuously stirring and then filtering and decolorizing; (2) pouring a filtrate into a crystallizer, stirring under constant temperature at 25-40 DEG C, adding alkali liquor into the crystallizer till pH of solutionis 5.0-5.8, adding a L-p-hydroxyphenylglycine methyl ester seed crystal and growing crystal for 1-3h; (3) continuing to add alkali liquor till pH of solution is 8.2-8.4, continuously cooling to 0-5 DEG C and growing crystal for 1-3h; (4) performing suction filtration, washing filter cake with water, and drying the acquired crystal product. The product acquired according to the invention is high in purity, large in grain size and high in liquidity; labor intensity of filtering and drying is low; the preparation method is easy for industrialization.

The invention discloses an HPLC method for determining the content of D(-)p-hydroxyphenylglycine in D(-)p-hydroxyphenylglycine methyl ester. The method is to prepare a solution of D(‑) p-hydroxyphenylglycine methyl ester with dilute acid solution, adopt a chemically bonded stationary phase chromatographic column, add organic base with buffer salt, and adjust pH to 0.8-12 with acid as buffer salt solution, buffered salt solution and organic phase modifier in an appropriate ratio for gradient elution, and then detect at an appropriate detection wavelength, flow rate and column temperature, and then calculate the sample content based on the spectrum. The method of the invention can effectively separate D(-)p-hydroxyphenylglycine methyl ester and D(-)p-hydroxyphenylglycine, and accurately measure the content of D(-)p-hydroxyphenylglycine. The method is simple, reliable and rapid , high sensitivity, good reproducibility and specificity, which established the foundation for the establishment of quality standards for D(‑) p-hydroxyphenylglycine methyl ester.