39results about How to "High stereoselectivity" patented technology

The invention discloses cyclohexene formate esterase, a mutant of cyclohexene formate esterase and application of cyclohexene formate esterase in production of (S)-3-cyclohexene-1-formic acid. According to the cyclohexene formate esterase and the mutant disclosed by the invention, 100-400g / L of racemic 3-cyclohexene-1-methyl formate can be split by taking wet thalli subjected to induced expression or crude enzyme liquid obtained by ultrasonically crushing the wet thalli as a catalyst, so that (S)-3-cyclohexene-1-formic acid with chemical purity and optical purity reaching 99% or above is synthesized. The enzyme activity of the cyclohexene formate esterase mutant provided by the invention is further improved, the reaction time and the catalyst dosage are obviously reduced compared with those of a substrate with the same catalysis concentration before mutation, the reaction condition is mild, the operation is relatively simple and convenient, and the cyclohexene formate esterase mutant has a very good industrial application prospect.

The invention provides an R-type transaminase mutant and application thereof, and compared with an amino acid sequence of wild-type transaminase as shown in SEQ ID NO.1, the mutant has mutation of a 62nd site, a 152nd site and a 155th site. The mutant has high catalytic activity and excellent stereoselectivity on a heterocyclic ketone substrate, and can be used for efficiently preparing R-configuration heterocyclic chiral amine.

The application belongs to the field of biopharmacy and bioconversion, and particularly relates to a lipase mutant and application thereof. The lipase CALB mutant of the application is obtained by adopting single-point mutation or combined mutation on positions 40, 134, 154, 189, 278 and 281 of the amino acid sequence shown in SEQ ID NO. 1. The mutant greatly improves the stereoselectivity in catalyzing the production of (S)-3-cyclohexene-1-methyl formate from racemic 3-cyclohexene-1-methyl formate. Compared with the traditional chemical method for preparing (S)-3-cyclohexene-1-methyl formate, the lipase CALB mutant provided by the application has high stereoselectivity, mild reaction conditions, is friendly to the environment, has reduced requirements on equipment, greatly reduces the production cost, and shows a wide application prospect in industrial application.

The application relates to the technical field of biotechnology, in particular to a dopamine reuptake inhibitor intermediate synthesis enzyme mutant and application, and amino acid sequences are shown in SEQ ID NO: 7-SEQ ID NO: 12. The stereoselectivity of asymmetric reduction catalysis of the dopamine reuptake inhibitor intermediate precursor is improved, the R-type dopamine reuptake inhibitor intermediate with high chirality purity is obtained, and the synthesis efficiency of the dopamine reuptake inhibitor intermediate is improved.

The invention discloses a planar chiral [2.2] paracyclophane alkane monophosphine ligand pEPCP as well as a preparation method and application thereof, and relates to the technical field of chemical catalysis, the planar chiral [2.2] paracyclophane alkane monophosphine ligand pEPCP is characterized by comprising a racemate or an enantiomer, and the structural formula I of the monophosphine ligand pEPCP is as follows: # imgabs0 #. Different types of ether substituents are introduced into the structure of a unique large-steric-hindrance electron-rich rigid skeleton formed by connecting two benzene rings at para-positions through two ethylidene groups, so that the electron cloud density and steric hindrance of aromatic rings directly connected with phosphine ligands are changed. In addition, the ether substituent can also be used as a weak coordination group and participates in adjusting a dihedral angle of ligand chelation. The metal, the ligand and the substrate form the most appropriate coordination environment in the catalysis process, so that the corresponding catalytic reaction has the advantages of high reaction activity, good enantioselectivity, wide substrate universal application range and the like, is particularly suitable for asymmetric coupling reaction catalyzed by transition metal, and has economic practicability and industrial application prospects.

Provided are a lipase mutant and an application thereof. Specifically, one or more mutations selected from A262H, A338V, V364I, A158P / V, and I159N are generated on the basis of an amino acid sequence as shown in SEQ ID NO: 1; and compared with a parental lipase, a change in the structure and function of a protein occurs in the lipase mutant, and the stereoselectivity is improved, such that a usage amount of an enzyme is decreased to a certain extent, the post-treatment difficulty is reduced, and the lipase mutant is suitable for industrial production.

The invention relates to the technical field of biology, in particular to a biological preparation method of a remegapam intermediate, which comprises the following steps: by taking remegapam intermediate precursor ketone with a certain concentration as a substrate, adding recombinant engineering bacteria, reacting in a reaction system with the pH value of 8.0-9.0 at the temperature of 30-40 DEG C, and obtaining a product after the reaction is completed, wherein the recombinant engineering bacterium is an engineering bacterium containing a ketoreductase mutant coding gene, and the amino acid sequence of the ketoreductase mutant is as shown in SEQ ID NO: 4, SEQ ID NO: 19 or SEQ ID NO: 39. According to the biological preparation method of the remegapam intermediate disclosed by the embodiment of the invention, the stereoselectivity of asymmetric reduction catalysis of the used ketoreductase mutant on precursor ketone of the remegapam intermediate is improved, the R-type remegapam intermediate with high chiral purity is obtained, and the synthesis efficiency of the remegapam intermediate is favorably improved.

The application provides a ketoreductase mutant and application thereof in synthesis of a key chiral intermediate of tigogaral, and provides a ketoreductase mutant with an amino acid sequence as shown in SEQ ID NO: 4, 6, 8, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40 or 42. The ketoreductase mutant has higher carbonyl catalytic activity and chiral selectivity than a wild type, and is used for preparation of a key intermediate R-5,7-difluorobenzodihydropyran-4-ol of tigogaral.

The invention provides a method for preparing chiral amine by catalyzing asymmetric hydrogenation of aromatic imine through a manganese / chiral ferrocene P, N, N ligand. The manganese precursor and ligand adopted by the method are easy to obtain, the reaction condition is mild, the operation is simple, the target chiral amine compound can be obtained with high yield and high stereoselectivity, and continuous large-scale preparation can be realized. The catalyst system is high in activity, the molar ratio of imine to the catalyst can reach 100000: 1, and the catalyst has a very good industrial application prospect.

This invention provides an imine reductase mutant, its preparation method, and its application in the catalytic preparation of dextromethorphan intermediates. The imine reductase mutant is an imine reductase with an amino acid mutation, comprising the amino acid sequence shown in SEQ ID NO:1. The amino acid mutation type includes any one or a combination of at least two of I122T, D212A, or G228R. By introducing a mutation into the imine reductase, this invention significantly improves the enzyme's activity and stereoselectivity, enabling the high-yield synthesis of the dextromethorphan intermediate (S)-1-(4-methoxybenzyl)-1,2,3,4,5,6,7,8-octahydroisoquinoline under mild conditions, greatly reducing production costs and making it suitable for industrial production.

This invention discloses a chiral monophosphine ligand, its preparation method, and its application in asymmetric synthesis. The ligand preparation method involves mixing an N,N',1,2-tetrasubstituted ethane-1,2-diamine compound, phosphorus trichloride, triethylamine, and solvent under a nitrogen or argon atmosphere at -80 to -70°C, and reacting at 60 to 80°C for 6 to 8 hours. The resulting reaction mixture is then cooled to room temperature, and an alcohol, phenol, or Grignard reagent is added dropwise, reacting at 60 to 80°C for 8 to 12 hours. The resulting mixture is then post-treated to obtain the chiral monophosphine ligand. The application involves stirring a nickel catalyst, a chiral monophosphine ligand, a solvent, a diene, and an aldehyde under an argon or nitrogen atmosphere at a specified temperature for 12 to 15 hours. The mixture is then post-treated to obtain the target product. This method utilizes widely available and inexpensive raw materials, and the operation is simple, achieving high stereoselectivity and enantioselectivity in the synthesis of alcohol compounds containing chiral conjugated dienes through a one-step reaction.

A cycloheptenone adduct of flavanols and stilbene compounds as shown in formula (I), its preparation method, and its use in treating cerebral ischemia. The compound of this invention has a simple preparation method and exhibits good neuroprotective activity.

Provided are a transketolase mutant, and an encoding gene and the use thereof, relating to the technical field of enzyme engineering. The transketolase mutant provided in the present invention has a sequence as set forth in SEQ ID NO:16 with an amino acid mutation. Provided are a high-stereoselectivity R transketolase mutant with an amino acid sequence of SEQ ID NO:1, a recombinant expression vector containing the encoding gene, a host cell containing the recombinant expression vector, a method for preparing the high-stereoselectivity R transketolase mutant, the use of the R transketolase mutant in catalyzing aromatic aldehyde to form high-stereoselectivity R-aromatic dihydroxyketone, and the use of the encoding gene in catalyzing aromatic aldehyde to form high-stereoselectivity R-aromatic dihydroxyketone. The stereoselectivity of p-methylsulfonephenyl dihydroxyketone produced under the catalysis of the mutant EcTK1_YYH is 95.2% ee (R), and a high activity and high steroselectivity are achieved.

The application discloses a neokotalanol derivative with a structural formula I and a preparation method and application thereof, designs a brand-new synthesis method, uses cheap and easily-obtained benzyl glucoside as raw material, successfully constructs a seven-ring glycoside intermediate with the same chiral center as the side chain of a natural product through five steps of reaction, uses the key seven-ring glycoside intermediate as raw material, and goes through a series of reactions to construct a coupling precursor with trifluoromethylsulfonyl as a leaving group, reacts with a benzyl-protected sulfur sugar, and goes through deprotection, reduction and other reactions to synthesize the neokotalanol and the derivative thereof, and the method completes the total synthesis of the neokotalanol and the synthesis of the derivative at a yield of 17%, which is 8.5 times of the highest yield reported.

This invention discloses a nitrile hydrolase mutant, an engineered bacterium, and its application in the synthesis of (R)-3-cyanohexanoic acid. The nitrile hydrolase mutant is obtained by single or multiple mutations at positions 135, 199, and 59 of the amino acid sequence shown in SEQ ID NO.2. This invention utilizes directed evolution technology to enhance the activity and stereoselectivity of the nitrile hydrolase by constructing a nitrile hydrolase mutant. Compared to the parental nitrile hydrolase PgNITmut, the enantiomeric selectivity (E value) of the mutant PgNITmut / F135L for the substrate 3-cyanohexanonilonitrile is increased from 332 to 419; the activity of the mutant PgNITmut / F135L / R199W is increased by 1.36 times, and the E value is increased to 461; the activity of the mutant PgNITmut / F135L / R199W / T59D is increased by 2.05 times, and the E value is increased to 569. The nitrile hydrolase mutant of this invention has high activity and stereoselectivity. It can be used to synthesize the chiral intermediate (R)-3-cyanohexanoic acid of buvasidan by a highly efficient nitrile hydrolase method, which greatly reduces the cost of industrial production and has good application prospects in the industrial production of buvasidan.

The application relates to a method for synthesizing a sugar nucleotide from UDP-D-Glc, wherein the synthesized sugar nucleotide is represented by the following formula I. The method comprises: using UDP-D-Glc as a starting sugar nucleotide, and preparing the sugar nucleotide of formula I through an enzyme catalytic reaction in the presence of an enzyme and a cofactor regeneration system by using a one-pot method at 30-40 DEG C. The method of the application reduces the production cost of the sugar nucleotide and the purification difficulty of the product by using a cofactor regeneration system to generate a cofactor in the synthesis of a common sugar nucleotide.

The application discloses a cytochrome P450 monooxygenase P450PL2 mutant and application thereof in the field of biotechnology. The P450PL2 enzyme derived from the doderlein bacillus DS-1 is subjected to multiple rounds of directional modification through the technical means of iterative saturation mutation, and a P450PL2 mutant with improved asymmetric hydroxylation activity is obtained, and the corresponding amino acid sequence is shown as SEQ ID No. 3. The P450PL2 mutant can be applied to catalyze the asymmetric hydroxylation of aryl ketone compounds to synthesize S configuration chiral alpha-hydroxy ketone compounds. The reaction has strict regioselectivity and stereoselectivity, and the operation process is simple and efficient.

This invention belongs to the field of enzymatic synthesis technology, specifically relating to a method for enzymatically synthesizing fucosylated novo-LNO series human milk oligosaccharide chains, comprising the following steps: using sialic acid-protected asymmetric branched oligosaccharide I as a substrate, firstly, fucosylation modification of the C3 branch site of the glycan chain is achieved through a fucosylation enzyme module; subsequently, galactose is introduced at the C6 branch end using a galactosylation enzyme module; finally, the sialic acid protecting group is removed by sialyl glycosidase to obtain the monofucosylated target product. By introducing sialic acid as a temporary protecting group into the asymmetric branched oligosaccharide I, the recognition of the reducing lactose and the internal LacNAc unit by fucosyltransferase is blocked, thereby selectively introducing fucose onto the non-reducing LacNAc / LNB unit, accurately constructing the branched structure.

The invention discloses a preparation method of a chiral hydrogenated carbazole skeleton compound, an asymmetric Diels-Alder reaction is catalyzed by a catalyst, an asymmetric catalytic system is a secondary amine-acid catalytic system, a dienophile is nitrogen-substituted-2 or 3-alkenyl indole, and a dienophile is beta-substituted-alpha, beta-unsaturated aldehyde, alpha-alkyl-alpha, beta-unsaturated aldehyde or alpha-alkyl-alpha, beta-unsaturated aldehyde. The invention also relates to a method for preparing the compound. The asymmetric Diels-Alder reaction of low-activity 3-alkenyl indole and 2-alkenyl indole with wide alpha, beta-unsaturated aldehyde is realized for the first time, so that a chiral hydrogenated carbazole skeleton containing a continuous chiral center and a full-carbon quaternary carbon chiral center and a polycyclic hydrogenated carbazole skeleton can be rapidly constructed; the method has the advantages of high yield, high stereoselectivity, mild conditions and the like, and is helpful for promoting research of synthetic methodology and pharmaceutical chemistry in related fields.

This invention discloses an alcohol dehydrogenase, recombinant genetically engineered bacteria, and their application in the asymmetric reduction of prochiral carbonyl compounds. The alcohol dehydrogenase exhibits excellent biological properties, achieving heterologous expression in engineered *E. coli* bacteria. When using whole cells as a catalyst, it can directly utilize intracellular coenzymes, achieving zero coenzyme addition. This enzyme possesses advantages such as high activity, high stereoselectivity, and a broad substrate spectrum, enabling green and efficient catalysis of the conversion of prochiral ketone compounds into corresponding chiral alcohols. This solves the problems of low conversion rate, low yield, low ee value, complex reaction process, and numerous byproducts in traditional chemical methods. The alcohol dehydrogenase of this invention exhibits excellent tolerance to isopropanol, allowing isopropanol to be used as a hydrogen source for coenzyme cycling. Furthermore, the byproducts of the enzyme-catalyzed reaction—acetone and the remaining isopropanol—can be separated and recovered through technical means, significantly reducing production costs.

This invention discloses a method for preparing alkenyl triazole compounds. Under the action of a base, alkynyl sulfonium salts and triazole compounds are reacted in an organic solvent at room temperature and pressure for 2–5 h to obtain alkenyl triazole compounds. This invention utilizes a diamine reaction at room temperature, requiring no additional catalyst or oxidant, exhibiting excellent functional group tolerance and broad substrate applicability, while also demonstrating good chemoselectivity, regioselectivity, and stereoselectivity. The reaction system is free of toxic metal catalysts, simple to operate, and demonstrates excellent functional group tolerance and broad substrate applicability. The raw materials used are inexpensive and readily available, exhibiting good atom economy and step economy, providing a new strategy for the synthesis of triazole series compounds. The entire reaction process is mild, with high product selectivity, simple operation, and environmental friendliness, conforming to the principles of green chemistry.

The invention belongs to the technical field of gene engineering and enzyme engineering, and particularly discloses a styrene monooxygenase mutant with high R-enantioselectivity. The mutant enzyme A59W can catalyze epoxidation of meta-substituted 3-fluorostyrene, 3-chlorostyrene and 3-bromostyrene to synthesize corresponding (R)-epoxide, the enantiomeric excess is more than 99%, and the mutant enzyme A59W is an excellent catalyst for synthesizing various drug intermediates.

The invention discloses a novel preparation method of baloxavir acid, comprising: taking a substrate (12aR)-12-[(11S)-7,8-difluoro-6,11-dihydrodibenzo[b,e]thiazine-11-yl]-7-(hexyloxy)-3,4,12,12a-tetrahydro-1H-[1,4]oxazino[3,4-c]pyrido[2,1-f][1,2,4]triazine-6,8-dione methanesulfonate, an organic reaction solvent and a dealkylation agent for reaction, and adding one or more of sodium thiosulfate and a hydrate thereof during the reaction. The sulfur atoms in the molecules of sodium thiosulfate and its hydrate have a certain affinity with the sulfur atoms in the substrate molecules, and a temporary interaction or coordination is formed between them during the reaction, thereby regulating the reaction product to transform toward a dominant stereo configuration and generate a desired product, thereby improving the stereoselectivity of the reaction, and reducing side reactions such as configuration flipping or isomerization of the substrate, so that the generation of baloxavir acid in the reaction process is dominant, the generation of isomers is inhibited, and the purity and yield of baloxavir acid are improved through post-treatment solid-liquid separation and purification.

The invention discloses a method for asymmetric hydrogenation of a pyrazolopyrimidine multi-nitrogen aromatic compound under the catalysis of manganese, and belongs to the technical field of asymmetric catalytic synthesis. Manganese and a chiral hydroxypyridine oxazoline ligand are used as catalysts, under the alkaline condition, a pyrazolopyrimidine multi-nitrogen aromatic compound and hydrogen are subjected to asymmetric hydrogenation in a solvent, and the chiral pyrazolotetrahydropyrimidine compound is obtained. According to the method, asymmetric hydrogenation of the pyrazolopyrimidine multi-nitrogen aromatic compound can be realized, the pyrazoloectoine compound with optical purity is obtained at high yield, and the enantiomeric excess can reach 97%. The method has the advantages of high enantioselectivity, simple and easy operation, easy preparation of the catalyst, mild reaction conditions, low energy consumption, environmental friendliness and good yield.

The present application relates to a kind of drug synthesis process of Tovorafenib.The synthesis process described in the present application, the preparation method of chiral alpha-heteroamine involved, using biological catalyst amine dehydrogenase, directly under mild conditions, one-step reduction amination of latent chiral ketone is into optical pure chiral alpha-heteroamine, it can overcome the deficiency of existing catalytic technology, process route is simple, reaction condition is mild, yield is high, has the advantages, such as step economy, atom economy and other green synthesis, and the advantages, such as good stereoselectivity (ee value is as high as 99%).The condensation method of amino and carboxyl in the synthesis route described in the present application is mostly under HATU and alkaline environment, simple operation, high reaction yield, suitable for batch production.

This application provides a method for the electrocatalytic synthesis of multisubstituted ribose derivatives, comprising using an organotin compound as a catalyst to catalyze the reaction of the compound shown in formula (I) under electrochemical conditions to obtain the compound shown in formula (II); wherein, R 1 C is an optional replacement 1‑10 hydrocarbon group; R 2 and R 3 One of them is -C(=O)OR, and the other is -H; R is the C that can be substituted. 1‑4 Alkyl; R 4 C is a hydrogen atom or an optional substituted C 1‑10 The method involves the use of a hydrocarbon group as the reaction solvent, a reaction temperature of 40-80℃, and a quaternary ammonium bromide as the electrolyte. This method enables the efficient and highly stereoselective synthesis of tetrasubstituted riboses modified with 2'- and 3'-ester groups, and is easily scaled up, showing promising prospects for industrial application. The products obtained by this method possess excellent potential for later derivatization and can be used to synthesize various novel nucleoside analogs, demonstrating significant application value in the development of antiviral and antitumor drugs.

This invention discloses a method for the deracemization of benzyl sulfoxide catalyzed by a dual-enzyme catalyst. The method includes the following steps: a) culturing and expressing genetically engineered bacteria producing cyclohexanone monooxygenase and sulfoxide reductase separately in LB medium, collecting the bacterial cells by centrifugation, and resuspending the cells in PBS buffer to obtain bacterial suspensions; b) mixing the two bacterial suspensions obtained in step a), racemic benzyl sulfoxide, DTT, and D-glucose, and reacting with shaking at 30°C; c) after the reaction is complete, extracting multiple times with an organic solvent, combining the organic phases, drying with anhydrous sodium sulfate, filtering, and recovering the solvent to obtain the target product. This invention achieves the deracemization of benzyl sulfoxide through dual-enzyme catalysis, resulting in a product with high optical purity and low raw material cost. The dynamic kinetic resolution method in aqueous solution is simple to operate, with mild reaction conditions, environmentally friendly operation, high substrate conversion rate, and good stereoselectivity.

This invention discloses a method for preparing silicon / germanium-glycoside compounds, belonging to the field of organic synthesis technology, comprising the following steps: adding a base, an olefin, a palladium catalyst, a ligand, a 5-haloenose, hexamethylsilyl (or hexamethylgerman), and an organic solvent sequentially to a dried reaction vessel, and reacting at 40-140°C for 6-36 hours; diluting the obtained material with ethyl acetate, then washing with water to separate the organic phase; drying, filtering, concentrating, and performing thin-layer chromatography or column chromatography to obtain the Si / Ge-glycoside compound. This invention can stereoselectively assemble various Si / Ge-glycoside compounds, with simple and safe procedures, and exhibits excellent chemoselectivity and broad functional group compatibility. This invention provides an efficient pathway for the development of Si / Ge-glycoside mimics with potential pharmaceutical activity and has important reference value for glycoside chemical modification and innovative drug development.

The application discloses a kind of generation (4R) 4-hydroxyisophorone monooxygenase mutant and its preparation method, the monooxygenase is derived from cytochrome P450 of bacillus megaterium BM3 Monooxygenase. The cytochrome P450 BM3 Monooxygenase mutant has high stereoselectivity and high reactivity to catalyze isophorone hydroxylation, mutant A74G / V78A / F87V / L188Q / T327A / A328F catalyzes isophorone to obtain (4R) The diastereomeric excess of 4-hydroxyisophorone can reach 99%, and the yield can reach 98%; the cytochrome P450 BM3 Monooxygenase mutant catalyzes isophorone synthesis (4R) 4-hydroxyisophorone production process is simple, reaction condition is mild, production process is environmental protection, is conducive to industrial production, and has wide application prospect.

This invention discloses a high-yield imine reductase mutant of R-type amino acid esters, its preparation method, and its applications. The wild-type imine reductase is derived from actinomycetes. Actinomadura welshii By using directed evolution to modify its active site, an imine reductase mutant with high activity, stereoselectivity, and high yield of (R)-2-((4-methoxyphenyl)amino)-2-phenylacetic acid methyl ester was obtained. The mutant is D98G / M122L / W216V / L15Y / A120V / T238M. This invention achieves efficient synthesis of (R)-2-((4-methoxyphenyl)amino)-2-phenylacetic acid methyl ester from inexpensive (trans)-2-((4-methoxyphenyl)amino)-2-phenylacetic acid methyl ester, which is beneficial for the industrial synthesis and application of (R)-2-((4-methoxyphenyl)amino)-2-phenylacetic acid methyl ester.