86 results about "Methyl mandelic acid" patented technology

The invention belongs to the technical field of daily chemistry, and provides a triple compound acid composition with skin brightening and acne removing effects, a product and application of the triple compound acid composition and the product, the triple compound acid composition comprises mandelic acid, salicylic acid and succinic acid, and the mass ratio of the mandelic acid to the salicylic acid to the succinic acid is (3-6): (1-2): (1-2). The invention further provides a product containing the composition and application of the product. The composition provided by the invention is synergistically used, has a synergistic effect in the aspect of exfoliating, especially in the aspect of improving the activity of kallikrein 5 (KLK5), not only has the effects of biological skin glowing and exfoliating, but also can efficiently down-regulate the expression of I-type 5alpha-reductase genes, so that the synthesis of sebum is inhibited, and an oil control effect is achieved; in addition, the composition provided by the invention has the effects of brightening, inhibiting bacteria and resisting inflammation, has low sensitization, can be used for removing acnes, takes effect quickly and does not relapse.

The invention provides p-hydroxymandelic acid synthetase, a gene, a mutant of the p-hydroxymandelic acid synthetase and application of the p-hydroxymandelic acid synthetase in asymmetric synthesis of (S)-mandelic acid. The p-hydroxymandelic acid synthetase disclosed by the invention is derived from actinomycetes Actinokineospora auranticola, the amino acid sequence of the p-hydroxymandelic acid synthetase is as shown in SEQ ID NO.1, and a mutant of the p-hydroxymandelic acid synthetase is obtained by performing single-point mutation or multi-point combined mutation on glutamic acid at the 187th site, isoleucine at the 189th site and threonine at the 211th site of the amino acid sequence as shown in SEQ ID NO.1. The p-hydroxymandelic acid synthetase and the mutant thereof can convert phenylpyruvic acid into (S)-mandelic acid with high optical purity, have the advantages of mild reaction conditions, simplicity and convenience in operation, safety, environment friendliness and the like, and have a very good industrial application prospect.

The invention relates to a polyacid composite oil-controlling and acne-removing gel and a preparation method thereof, and belongs to the technical field of skin care products. The polyacid composite oil-controlling and acne-removing gel is prepared from the following components in percentage by mass: 2% of salicylic acid, 3%-4% of glycolic acid, 0.5%-1.5% of mandelic acid, 0.5%-1.0% of lactobionic acid, 0.5%-1.0% of gluconolactone, 1.2%-1.6% of microcrystalline cellulose (and) sphingomonas fermentation product extract (and) cellulose gum, 2%-5% of butanediol, 0.3%-0.5% of asiaticoside-II, 0.5%-1.5% of centella asiatica, 0.5%-1.5% of vitamin E and the balance of water. And the balance of deionized water. By adding micro-crystalline cellulose (and) sphingomonas fermentation extract (and) cellulose gum, system stability under compounding of five organic acids is realized, semitransparent gelatinous texture is obtained, the composition is suitable for point coating use mode, impression is not affected, oil-controlling and acne-removing effects are improved under the condition of low organic acid content, and the composition belongs to skin-care polyacid products and has a broad market prospect. The mild oil control and acne removal effects are realized, and the cream is suitable for oil-sensitive skin crowds.

The invention discloses a penicillin G acylase mutant with high synthetic activity and low hydrolytic activity and application of the penicillin G acylase mutant, and belongs to the field of bioengineering. The penicillin G acylase gene derived from Escherichia coli is subjected to site-specific mutagenesis, so that the amino acid sequence coded by the penicillin G acylase gene mutates from phenylalanine F to alanine A at the 24th site of an alpha chain, the 146th site of the alpha chain mutates from phenylalanine F to valine V, and the 386th site of a beta chain mutates from serine S to alanine A to obtain the mutant. According to the penicillin G acylase mutant alphaF24A / betaS386A disclosed by the invention, compared with the conversion rate of cefamandole synthesized by catalyzing the reaction of methyl mandelate and 3-(1-methyl-1H-tetrazole-5-yl) thiomethyl-7-aminocephalosporanic acid (7-TMCA) within 4 hours before mutation, the conversion rate of cefamandole synthesized by catalyzing the reaction of methyl mandelate and 3-(1-methyl-1H-tetrazole-5-yl) thiomethyl-7-aminocephalosporanic acid (7-TMCA) is improved by 13.70%, and the yield of a side reaction product mandelic acid is reduced by 82%. The penicillin G acylase mutant disclosed by the invention can be used for catalyzing methyl mandelate and 7-TMCA to synthesize cefamandole while greatly reducing the occurrence of side reactions, and can be applied to preparation of cephalosporin antibiotics.

The invention relates to the technical field of cosmetics, in particular to a preparation method of a supramolecular acid enzyme composition and application of the supramolecular acid enzyme composition in cosmetics. The preparation method comprises the following steps: preparing a deep eutectic solvent which is in a liquid state at normal temperature, and reacting protease with the deep eutectic solvent to prepare the liquid supramolecular acid enzyme composition. The supramolecular acid enzyme composition is used for preparing cosmetics for removing waste cutin, blocking pores and promoting skin metabolism. According to the stable and reliable enzyme immobilization method, the supramolecular deep eutectic solvent is prepared from the mandelic acid and the betaine, the papain and the bromelain are dissolved and immobilized in the supramolecular deep eutectic solvent, and the method has the advantages of being easy to operate, good in solubility, good in stability and the like; in addition, the finally obtained supramolecular acid enzyme composition also can realize the combination of acid and enzyme, so that the effects of synergistically removing waste cutin and blocked pores of the skin, quickly improving the texture and appearance of the skin and promoting the metabolism of the skin are achieved.

The invention discloses a high-temperature-resistant self-repairing coating and a preparation method thereof, and relates to the technical field of coatings. The high-temperature-resistant self-repairing coating prepared by the invention comprises modified polyurethane, modified carbon nanotubes, a defoaming agent, an auxiliary agent, a curing agent, a solvent and a flatting agent, and the modified polyurethane is obtained by reacting piperazinyl-terminated polysiloxane with isocyanate and then grafting alkenyl iodo-boron dipyrromethene; the modified carbon nano tube is obtained by grafting an acylating chlorination carbon nano tube with 2-tert-butyl-4-aminophenol, then reacting with DL-3, 4-dihydroxy mandelic acid, and finally reacting with 1, 4-phenylboronic acid. The high-temperature-resistant self-repairing coating prepared by the invention has good antibacterial, anti-aging and self-repairing properties.

The invention provides a method for synchronously detecting eight catecholamines and metabolites thereof based on liquid chromatography-tandem mass spectrometry and application of the method. The detection method comprises the following steps: mixing a plasma or urine sample to be detected with an internal standard and acetonitrile; centrifuging, taking supernate, blowing liquid with nitrogen, and adjusting the pH value; mixing the supernate with a propionic anhydride solution, and carrying out derivatization reaction to obtain a test solution; performing liquid chromatography-tandem mass spectrometry detection on the test solution and the standard solution, separating dopamine, epinephrine, noradrenaline, epinephrine, noradrenaline, 3-methoxytyramine, homovanillic acid and vanillic mandelic acid by liquid chromatography, and determining the concentration of the standard substance as an X axis by using a mass spectrometry isotope internal standard quantification method. The ratio of the peak area of the standard substance to the peak area of the internal standard substance is the Y axis, establishing a standard curve, and calculating the concentrations of catecholamine and the metabolites thereof in the test solution. The method is high in detection efficiency, high in sensitivity and good in equipment compatibility, the detection time is shortened, and the cost can also be saved.

The invention relates to an allergy-relieving acne-removing composition and a preparation method and application thereof, and the allergy-relieving acne-removing composition comprises the following raw materials in parts by mass: 1-10 parts of VB-IP, 5-20 parts of hydroxyethyl urea, 1-5 parts of coated salicylic acid, 2-10 parts of wild soybean, 1-5 parts of clerodendranthus spicatus, 1-5 parts of rosewood seeds, 1-10 parts of lactobionic acid, 1-10 parts of gluconolactone, 1-10 parts of mandelic acid, 1-10 parts of glycollic acid, 1-5 parts of octyl dodecyl glucoside and 1-5 parts of cetearyl glucoside. 0.5 to 2 parts of phenoxyethanol and 5 to 30 parts of deionized water; the composition comprises the following components: a wild soybean fermentation extract, a clerodendranthus spicatus fermentation extract and a rosewood seed fermentation extract. Compared with the prior art, the formula is stable, penetration can be promoted, cutin renewal can be accelerated, a sebum film can be repaired, sebum can be adjusted, and the acne removing and skin care effects are good.

The invention discloses a composition for relieving, repairing and promoting skin regeneration as well as a preparation method and application of the composition. The composition is prepared from the following raw materials in parts by weight: 0.1 to 5 parts of mandelic acid, 0.5 to 10 parts of a cynanchum atratum extract, 1 to 8 parts of a xylitol compound, 0.5 to 15 parts of regenerated silicon, 1 to 10 parts of a starfish regeneration repair factor, 0.3 to 1.5 parts of trimethylolpropane tri (3-mercaptopropionic acid) ester, 0.05 to 0.5 part of calcium chloride, 0.1 to 1 part of an additive, 0.2 to 2 parts of chitosan-polycaprolactone, 0.2 to 1 part of a pH regulator and 5 to 15 parts of a solvent. 0.3 to 0.8 part of an antioxidant and 3 to 10 parts of a humectant; the additive is hyaluronic acid or formylated hyaluronic acid. Through a multi-channel synergistic effect, the effects of relieving, repairing and promoting skin regeneration are improved.

The application belongs to the technical field of pharmaceutical chemistry, and particularly relates to clofazimine-organic acid co-crystals, a preparation method and application thereof. The clofazimine-organic acid co-crystal is one of clofazimine-ferulic acid monohydrate co-crystal, clofazimine-ferulic acid co-crystal, clofazimine-glutaric acid co-crystal, clofazimine-glycolic acid co-crystal (CFZ-GA 1:1), clofazimine-glycolic acid co-crystal (CFZ-GA 1:1.5), clofazimine-salicylic acid co-crystal, clofazimine-L-aspartic acid co-crystal, clofazimine-L-pyroglutamic acid co-crystal, clofazimine-gallic acid co-crystal, clofazimine-succinic acid co-crystal, clofazimine-tartaric acid co-crystal and clofazimine-DL-mandelic acid co-crystal. The clofazimine-organic acid co-crystal provided by the application significantly improves the solubility and fluidity of clofazimine, thereby improving the bioavailability of clofazimine, and has a broad medicinal prospect.

The invention belongs to the technical field of medicinal chemistry, and particularly relates to a melogabalin-S-mandelic acid crystal form and a preparation method thereof. According to the crystal form, a basic structural unit is composed of one molecule of melogabalin and one molecule of S-mandelic acid, the solubility and storage stability of melogabalin are improved, the impurity content is reduced, the product quality is improved, meanwhile, the preparation method is simple, convenient and easy to operate, and the crystal form has a good application prospect in industrial production.

The invention provides a cosmetic composition and a preparation method thereof. In particular, the cosmetic composition comprises: a linear saturated dicarboxylic acid having 4 to 10 carbon atoms; mandelic acid or a derivative thereof; and polyaspartic acid or a derivative thereof. The cosmetic composition according to the technical scheme of the invention contains higher content of straight-chain saturated dicarboxylic acid with 4-10 carbon atoms, and has excellent cutin removal and acne inhibition effects when azelaic acid is used as the straight-chain saturated dicarboxylic acid with 4-10 carbon atoms.

The present invention relates to the technical field of compounds for medicine and cosmetics, and particularly relates to an mandelic acid ionic liquid, a preparation method and an application thereof. The present invention combines matrine and mandelic acid through an ionic bond to obtain the mandelic acid ionic liquid, which increases the water solubility and percutaneous permeability of the two monomers. The mandelic acid ionic liquid simultaneously improves the low solubility of matrine and the permeability of mandelic acid. While increasing the available range of the two substances, the mandelic acid ionic liquid simultaneously has the advantages of both matrine and mandelic acid; moreover, the mandelic acid ionic liquid has good permeability, cell and biocompatibility, good solubility and no irritation, and has the characteristics of oil control, soothing, high bioavailability and stable properties when applied to cosmetics.

The present invention discloses the construction and application of a recombinant Gluconobacter oxydans, belonging to the fields of genetic engineering and whole-cell catalysis. The present invention heterologously expresses an epoxide hydrolase from Sphingomonas in Gluconobacter oxydans, and simultaneously utilizes the alcohol and aldehyde dehydrogenases bound to the membrane of Gluconobacter oxydans itself to synthesize R-mandelic acid in a one-step process using styrene oxide as a substrate. The present invention combines the transcriptome data of Gluconobacter oxydans, screens 7 strong promoters using green fluorescent protein as a reporter gene, and determines the strongest promoter P for expressing the epoxide hydrolase gene. 12780 , ultimately significantly increasing the yield of R-mandelic acid.

The preparation of high-value-added aromatic carboxylic acids via CO2 carboxylation coupling through activation of the benzyl C-H bond in alcohols / amines is a green and sustainable pathway to achieve CO2 resource utilization and contribute to carbon neutrality. However, this field currently faces challenges such as poor catalyst selectivity, low CO2 activation efficiency, and a narrow substrate applicability range, making it difficult to meet practical application needs. To address this issue, this patent discovers that in a heterogeneous electrocatalytic system, cuprous selenide (V2), rich in selenium vacancies, can be used... Se -Cu 2‑x Using Se as the core catalyst, it can not only efficiently promote the synergistic activation of benzyl C-H bonds and CO2 carboxylation, significantly improving the overall catalytic activity of the reaction, but also achieve precise chemoselective carboxylation control for different types of substrates. Specifically, this V Se -Cu 2‑x Se electrocatalysts can efficiently and selectively activate the benzyl C-H bond in alcohols and subsequently induce CO2 carboxylation, exhibiting excellent chemoselectivity in the conversion of benzyl alcohol to mandelic acid and its derivatives. Simultaneously, they also demonstrate excellent catalytic performance for amines, selectively catalyzing the carboxylation of amine substrates such as benzylamine with CO2 to directionally generate phenylglycine and aromatic amine-derived carboxylates. Crucially, in addition to typical benzyl alcohol and benzylamine, the substrate applicability of this catalytic system can be extended to various alcohols and amine derivatives, realizing the carboxylation transformation from simple model substrates to diverse functional molecules, providing a new approach for the large-scale preparation of high-value-added aromatic carboxylates.

The present invention belongs to the field of medicinal chemistry and relates to a triazine-thiazolidinone compound and its preparation method and application. Its structural formula is wherein R1 is any one of alkyl, pyranyl, indolyl, phenyl or thienyl. Its pharmaceutically acceptable salt is the acid salt of the compound, and the acid is any one of hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, boric acid, methanesulfonic acid, p-toluenesulfonic acid, naphthalenesulfonic acid, benzenesulfonic acid, citric acid, lactic acid, pyruvic acid, tartaric acid, acetic acid, trifluoroacetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, salicylic acid or phenylacetic acid. The triazine-thiazolidinone compound skeleton provided by the present invention is novel, has a good inhibitory effect on glucose transporter 1 (GLUT1), and its inhibitory effect in HT29 cells is much better than that of positive control compound BAY-876, with good potential for further development as an anti-tumor drug.

Disclosed herein are topical compositions comprising Centella asiatica extract and mandelic acid, wherein the compositions have a pH of less than 5, and methods of using the compositions to decrease cellular senescence in skin and treat dermatoporosis. Topical compositions comprising Centella asiatica extract and mandelic acid are effective to reduce the number of senescent cells in mammalian dermis, reduce the senescence-associated secretory phenotype (SASP), downregulate at least one SASP-associated gene, increase the expression of at least one cell cycle-related gene in dermal fibroblasts, downregulate at least one gene associated with skin inflammation, and increase fibroblast cell turnover.

The invention discloses a bio-based nonionic dispersant and a preparation method thereof, and belongs to the field of chemical engineering. According to the preparation method, mandelic acid and fatty alcohol which are biologically sourced are adopted as raw materials, bio-based mandelic acid ester containing a mandelic acid structure is obtained through a simple esterification reaction, then the bio-based mandelic acid ester and ethylene oxide are subjected to a ring-opening polymerization reaction, and the bio-based dispersing agent with a novel structure is obtained. And pigment color paste prepared by using the polycarboxylate superplasticizer as a dispersing agent has the characteristics of small pigment particle size, narrow distribution and good stability, and the polycarboxylate superplasticizer is low in price, easy to obtain, low in potential toxicity and biodegradable.

The invention provides atomoxetine hydrochloride and a preparation method thereof, and relates to the technical field of medicinal chemistry and organic synthesis. The method provided by the invention comprises the following steps: adopting acetophenone, methylamine hydrochloride and a formaldehyde aqueous solution as raw materials, carrying out Mannich reaction to construct a beta-amino carbonyl skeleton, reducing carbonyl into hydroxyl by adopting sodium borohydride, then reacting with di-tert-butyl dicarbonate to form an amino protecting group, adopting o-methylphenol as a raw material, and preparing the beta-amino carbonyl skeleton. The method comprises the following steps: adding p-toluenesulfonic acid monohydrate and a (2-hydroxybenzyl) phosphine oxide catalyst to construct an ether bond through a Mitsunobu reaction, then removing a t-butyloxycarboryl protecting group, and carrying out chiral resolution and salinization reaction by using S-mandelic acid to obtain atomoxetine hydrochloride. The method of dropwise adding the formaldehyde aqueous solution in batches and controlling the reaction temperature is adopted, so that the generation of impurities can be reduced, and the yield is effectively improved; the p-toluenesulfonic acid monohydrate and the (2-hydroxybenzyl) phosphine oxide catalyst capable of participating in catalytic circulation are used for catalyzing the Mitsunobu reaction, the economic principle is met, and the purity and the yield of the product are greatly improved.

Methods and compositions suitable for treating acne, disrupting biofilms, and / or killing bacteria contained in biofilms are provided. [Solution] A particular method involves contacting skin requiring such treatment with a composition comprising two α-hydroxy acids and a polyhydroxy acid. Another particular method involves applying a composition comprising a first α-hydroxy acid, a second α-hydroxy acid, and a polyhydroxy acid to a surface having a biofilm. A particular composition is a. Glycolic acid in an amount of approximately 0.1% to 7.5% by weight, b. Approximately 0.1% to 5% by weight of gluconolactone, c. Approximately 0.1% to 5% by weight of mandelic acid, d. Glycol and, e. Salt-resistant thickening polymer, It contains, and the total amount of glycolic acid, gluconolactone, and mandelic acid is less than about 15% by weight of the total composition.

The invention relates to the technical field of oilfield chemistry, in particular to an environment-friendly biological blocking remover for oil extraction and a processing technology of the environment-friendly biological blocking remover. The environment-friendly biological blocking remover is prepared from the following components in percentage by weight: 4 to 6 percent of alkyl glycoside, 4 to 6 percent of sophorolipid, 3 to 5 percent of methylglycine diacetic acid, 5 to 8 percent of rhamnolipid, 6 to 8 percent of compound microorganism fermentation liquor, 5 to 8 percent of lipase, 5 to 8 percent of protease, 6 to 8 percent of polymer degrading enzyme, 2 to 4 percent of citric acid, 2 to 4 percent of mandelic acid, 1 to 2 percent of glycerol, 1 to 2 percent of trehalose and 31 to 57 percent of deionized water. The biological enzyme, the biological surfactant, the organic acid and the chelating agent cooperate to fundamentally disintegrate blockages, meanwhile, the microcapsule technology and the nano-bubble technology are used, the action period is greatly prolonged, blockages of deeper parts can be treated, and the treatment effect is good. And corrosion and damage of strong acid and strong alkali to underground pipe columns, tools and stratum rocks are avoided, and secondary damage caused by plug removal operation is prevented.

The invention discloses a nitrilase mutant with high activity and stereoselectivity and application of the nitrilase mutant in synthesis of chiral carboxylic acid. The mutant is obtained by performing single mutation or multiple mutation on 79th, 166th, 167th and 246th amino acids of an amino acid sequence shown as SEQ ID NO.1. The invention further discloses a preparation method of the nitrilase mutant. According to the invention, the nitrilase OsNIT-mut is subjected to molecular modification through (semi) rational design, and a mutant with synergistically improved hydrolysis reaction specificity and stereoselectivity is obtained. The content of mandelic acid in a product of the mutant OsNIT-mut / V246N / T166G / R79Y / A167N for catalyzing mandelonitrile is 90.5%, the e.e. Value of R-mandelic acid is increased to 95.2%, and the relative hydrolytic activity is 399.1%. The nitrilase mutant can be applied to green industrial catalytic synthesis of chiral mandelic acid through regulation and control of hydrolysis reaction specificity and stereoselectivity, and has important significance.

The invention relates to the technical field of cosmetics, in particular to a preparation method of a supramolecular oleic acid control enzyme composition and application of the supramolecular oleic acid control enzyme composition in cosmetics. The invention relates to a preparation method of a supramolecular controlled oleic enzyme composition. The preparation method comprises the following steps: preparation of a supramolecular NaDES solvent: carrying out a reaction on mandelic acid, betaine and capryloyl glycine to obtain the supramolecular NaDES solvent; preparation of a supramolecular acid enzyme composition: reacting the papain and bromelain compound with a supramolecular NaDES solvent to obtain the supramolecular acid enzyme composition; mandelic acid, betaine and capryloyl glycine are prepared into a supramolecular deep eutectic solvent and a protease compound, and the protease compound is immobilized in the supramolecular deep eutectic solvent, so that the method has the characteristics of simplicity in operation, good solubility, good stability and the like; the finally obtained supramolecular oleate-controlling enzyme composition can realize the combination of acid, amino acid derivatives and enzyme, and achieves the effects of synergistically removing waste cutin and blocked pores of skin, controlling oil, quickly improving the texture and appearance of skin and promoting metabolism of skin.

The present invention discloses a Gluconobacter oxydans strain tolerant to high concentrations of mandelic acid and its application, belonging to the fields of microbial engineering technology and genetic engineering. In the present invention, Gluconobacter oxydoacetici 621H is used as the starting strain, and Gluconobacter oxydoacetici is subjected to adaptive evolution by gradually adding mandelic acid to the culture medium. The evolved strain has significantly improved tolerance to mandelic acid. Applying the strain Gluconobacter oxydans STA to catalyze the synthesis of R-mandelic acid from styrene oxide, both the yield and the conversion rate are significantly improved. Using the genetically engineered Gluconobacter oxydans strain constructed by the present invention to catalyze the synthesis of R-mandelic acid from styrene oxide, the final yield reaches 14.06 g / L, while that of the wild strain WT is only 10.26 g / L; the catalytic efficiency is also greatly improved, increasing from 0.366 g / L / h to 0.703 g / L / h.

Chiral purification method of key intermediate of GLP-1 receptor agonist. The present invention belongs to the field of organic chemical synthesis. To solve the problem that it is difficult to obtain a high-purity product of (S)-oxetan-2-ylmethanamine prepared by the current process route, the technical solution provided by the present invention is as follows: 1) The compound of formula V is salted with an acid to form the compound of formula VI; 2) The compound of formula VI is freed under alkaline conditions to obtain the compound of formula VIII. The beneficial effects of the present invention are: By using the purification method of synthesizing (S)-oxetan-2-ylmethanamine of the present invention, the product has good stability after being salted with D-tartaric acid / D-mandelic acid and is not easily decomposed and ring-opened. Then, free with a base to achieve the effect of chiral resolution, so that the ee value of the final product VIII reaches more than 98%. The operation is convenient, avoiding the use of high-risk solvents such as 36% concentrated hydrochloric acid, and improving the operability of the process.

The application discloses a preparation method of (2R, 5S)-4-Boc-2, 5-dimethyl piperazine. Trans-2, 5-dimethyl piperazine is used as raw material, reacts with di-tert-butyl dicarbonate to generate N-Boc-2, 5-dimethyl piperazine, then is subjected to splitting by L-(+)-mandelic acid to obtain (2R, 5S)-4-Boc-2, 5-dimethyl piperazine mandelic acid salt, and then is separated to obtain 2R, 5S)-4-Boc-2, 5-dimethyl piperazine. The raw material used in the application is cheap and easy to obtain, the reaction condition is mild, the operation is simple, the total reaction yield is high, and the application is suitable for industrial production.

The present invention provides a method for preparing enantiopure α-methoxyphenylacetic acid. The method comprises: using (R / S)-mandelic acid as the main raw material, performing an O-alkylation reaction with a methylating agent in the presence of an alkaline reagent, followed by purification and dissociation using an organic base to obtain enantiopure α-methoxyphenylacetic acid with a purity of up to 99.0%. The method achieves a maximum yield of 88.6% in an aprotic mixed solvent. This process reduces the amount of methylating agent used and increases the conversion rate to 99.5%. The organic base salt formation purification is efficient, produces a good crystal form, and is easily filtered. The process is simple, highly safe, and suitable for industrial-scale production.

The invention relates to a preparation method of a mandelic acid derivative, which adopts a commercially available conventional p-chlorphenyl magnesium bromide reagent as a raw material, the cost is low, the p-chlorphenyl magnesium bromide reagent is easy to obtain, the cost of the raw material is reduced by more than 40%, and the synthesis steps are simple, the cost is lower, the toxicity is lower, the operation is convenient, and the safety is high.

The invention discloses a chitosan / sodium carboxymethyl cellulose / calcium ion antibacterial composite hydrogel self-supporting membrane as well as a preparation method and application thereof. The composite hydrogel membrane takes nano-hydroxyapatite as a multifunctional calcium source and an adsorption enhancing component, and chitosan and sodium carboxymethyl cellulose are crosslinked through mandelic acid steam to form a dual-network matrix. The hydrogel film prepared by the method has the advantages of large metal ion adsorption capacity, excellent antibacterial property, good mechanical property and the like, and can realize the targets of high-efficiency removal of heavy metal ions in industrial wastewater and low-consumption pollution degradation.

This invention provides a method for producing safinamide and its salts that have high optical purity with reduced enantiomerity. [Solution] A method for producing a salt of safinamide having high optical purity is provided, by contacting a mixture containing safinamide and its enantiomers with an acid selected from the group consisting of L-tartaric acid, L-glutamic acid, and D-mandelic acid in a reaction solvent.