1345results about How to "High stereoselectivity" patented technology

The invention discloses a method for preparing aliphatic polycarbonates by catalyzing by the metal cyanide coordination catalyst. In a high pressure reactor, the metal cyanide coordination catalyst is utilized to catalyze epoxide and carbon dioxide body or solution copolymerization, wherein, the copolymerization temperature is 20-150 DEG C; the carbon dioxide pressure is 0.5-10MPa; the reaction time is 1-48h; the catalyst concentration is 1-100kg epoxide/g catalyst; the polymerization activity is more than 1.0kg of polymer/g catalyst; the weight-average molecular weight of the copolymer is more than 80 thousand; the molecular weight distribution is 1.5-4; the alternation degree of the copolymer is more than 90%; the cyclic carbonate by-product is less than 5wt%; the CO2 fixed rate of CO2/epoxypropane copolymer is more than 40wt%; and the CO2 fixed rate of CO2/cyclohexene oxide copolymer is more than 30wt%.

The invention belongs to the field of medicine and chemical engineering and particularly relates to a preparation method of tofacitinib citrate. The method comprises steps as follows: 1-benzyl-4-methyl-2,6-dihydro-3-piperidone taken as a starting material is subjected to an asymmetric reduction reaction, 1-benzyl-4-methyl-3-piperidone is obtained, and (3R,4R)-cis-1-benzyl-4-methyl-3-methylamino-piperidine dihydrochloride is produced under the action of a chiral catalyst; (3R,4R)-cis-1-benzyl-4-methyl-3-methylamino-piperidine dihydrochlorid and a paratoluensulfonyl chloride protection product 4-chloro-7-(methyl-4-benzenesulfonyl) pyrrolo[2,3-d]pyrimidine of 4-chloropyrrolo[2,3-d]pyrimidine are subjected to a condensation reaction, [(3R,4R)]-1-benzyl-4-methyl-piperidine-3-yl]-methyl-(7H-pyrrolo[2,3-d]pyrimidine-4-yl)-amine is obtained through deprotection, and tofacitinib citrate is obtained through debenzylation protection, an acylation reaction and citric acid salifying. The process route is short, the process cycle is short, chiral synthesis is performed by means of a catalyst, the product purity is improved, the cost is reduced, the yield is high, and the operation is simple and convenient.

The invention discloses a quinolizinones compound which comprises an optical isomer, a raceme and a cis-trans-isomer and a random combination or pharmaceutical salt thereof. A structure of the quinolizinones compound is as shown in a formula I: (with reference to the specification), wherein one of V and Y is O, and the other one of V and Y is CR8R9; R8 and R9 respectively independently are hydrogen or C1-6 alkyl. The invention further discloses a preparation method and application of the compound in the formula I. The compound in the formula I can obviously reduce a HBsAg (Hepatitis B surface antigen) level in vivo and meanwhile, inhibit replication of a HBV (Hepatitis B Virus), wherein when V or Y is O, solubility of the compound is obviously improved, the compound has excellent medicinal attributes and meanwhile, is also low in toxicity, pharmacokinetics and pharmacodynamics functions are improved, efficiency of combining with the HBV can be greatly improved, and a clearance ratio of the HBV in vivo can also be further improved.

The invention discloses a gene of dicarbonyl reductase. The nucleotide sequence of the gene has over 80 percent of homology with SEQ ID NO.1. The dicarbonyl reductase consists of an amino acid sequence having over 80 percent of homology with SEQ ID NO.2. The obtained dicarbonyl reductase can be used for a reaction of catalyzing a dicarbonyl compound to be reduced into a dicarbonyl product, and has high stereo-selectivity.

The present invention relates to novel monooxygenase nucleic acids and polypeptides created using mutagenesis, DNA shuffling, or both, in a single iteration or multiple iterations, and methods for their creation and use. The monooxygenase enzymes of the present disclosure have particular utility as biocatalysts in industrial chemical redox reactions, such as the oxidation of aromatic hydrocarbons, for example, toluene, benzene, or nitrobenzene, into industrially desirable products. The systems and processes of the present invention are especially useful for the coupled synthesis and recovery of catechols, methylcatechols, resorcinols, methylresorcinols, hydroquinones, methylhydroquinones, hydroxybenzenes, cresols, nitrobenzenes, and nitrohydroxyquinones.

The invention provides a Pichia guilliermondii X25 which is enriched and screened from soil, has high diastereoselectivity and is a carbonyl reductase active microbial new strain, and application of the Pichia guilliermondii X25 in preparation of 6-cyano-(3R, 5R)-dyhydroxyl hexanoic acid tert-butyl ester by biological asymmetric reduction (R)-6-cyano-5-hydroxyl-3-carbonyl hexanoic acid tert-butylester. The strain is preserved in China Center for Type Culture Collection (CCTCC), the address is Wuhan university, Wuhan, China, the post code is 430072, the CCTCC No. is M 2011386, and the preservation date is November11th,2011. The optical pure 6-cyano-(3R, 5R)-dyhydroxyl hexanoic acid tert-butyl ester prepared by using carbonyl reductase generated by the Pichia guilliermondii X25 to convert (R)-6-cyano-5-hydroxyl-3-carbonyl hexanoic acid tert-butyl ester is high in stereoselectivity, mild in reaction condition and environment-friendly.

The invention provides a soluble temperature sensitive polymer chiral catalyst, namely a polymer material copolymerized by L-proline derivatives and N-isopropylacrylamide. The catalyst is prepared by following steps: taking azodiisobutyronitrile (AIBN) as the initiator, and N,N-dimethylformamide (DMF) as the solvent, and then carrying out copolymerization reactions between N-isopropylacrylamide and free radicals of (s)-O-acryloyl-4-hydroxy-L-proline. The catalyst is capable of being used to catalyze asymmetric aldol condensation reactions, and has the advantages of high catalytic activity and good stereo-selectivity. The catalyst is capable of being used in an ordinary organic solvent system; furthermore, because the catalyst has a temperature sensitive effect, the catalyst is easy to be separated from the water system and recycled, the catalyst is an important way to achieve green organic synthesis, and has a vast application prospect.

The invention relates to a chiral diphosphine ligand and a chiral catalyst, and a preparation and application method thereof. The preparation method of a BINAP (2,2'-bis(diphenylphosphino)-1,1'-binaphthyl) chiral diphosphine ligand based on novel imidazole and imidazole cation modification. Imidazole and imidazole cation are introduced to the 5,5'- position of the BINAP molecule framework to synthesize the chiral diphosphine ligand. The assembly of the imidazole and imidazole cation into the chiral diphosphine ligand molecule can effectively enhance the stability of the chiral catalyst in an ionic liquid and the affinity with the imidazole ionic liquid, and avoids loss of the catalyst in the cyclic process. The imidazole-modified chiral diphosphine ligand has the following chemical structural formula, wherein the spatial configuration of the imidazole-modified chiral diphosphine ligand is S type or R type.

The invention discloses a rhizopus microsporus root-shaped variant ZJPH1308 and application thereof in preparation of a sitagliptin intermediate. A strain of the rhizopus microsporus root-shaped variant ZJPH1308 can be used for biologically and asymmetrically reducing 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazol[4,3-a]pyrazine-7-(8H)-yl]-1-(2,4,5-trifluorophenyl)butanone so as to obtain (S)-3-hydroxyl-1-[3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazol[4,3-a]pyrazine-7-(8H)-yl]-4-(2,4,5-trifluorophenyl)butanone. The strain has the advantages of good three-dimensional selectivity, high product optical purity and the like. The rhizopus microsporus root-shaped variant ZJPH1308 is fermented and cultured to obtain a wet thallus which serves as chiral biological catalyst; when the substrate concentration is 10mmol/L, the reduction product yield is as high as 95%, and the e.e. value of the product is greater than 99.9%.

The invention relates to a method for synthesizing chiral beta-acetenyl ketone by catalytic intermolecular decarboxylation from beta-ketonic acid and a propargyl compound. A chiral copper catalyst adopted in the invention is synthesized in stiu from a copper salt and a chiral P,N,N-tridentate ligand in various polar solvents and nonpolar solvents. According to the invention, various chiral beta-acetenyl ketone compounds with substituent groups can be synthesized conveniently, and can obtain a percent enantiomeric excess as high as 95%. The method in the invention is advantaged by operational simplicity, available raw materials, wide substrate application range, high enantioselectivity, and the like.

The invention discloses a novel strain, namely candida parapsilosis ZJPH1305 and application thereof in preparation of high optical purity (5S)-(4-fluobenzene)-5-hydroxyvalerate by virtue of microbial catalytic asymmetric reduction of a 5-(4-fluobenzene)-5-keto pentanoic acid. The e.e value of a target product (5S)-(4-fluobenzene)-5-hydroxyvalerate achieves 99.9% and the yield achieves 95.37% when the concentration of a substrate is 47.62mmol/L and the final concentration of cosubstrate glucose is 100g/L by virtue of chiral biocatalysis of adopting the candida parapsilosis ZJPH1305 cell as a catalyst.

The invention relates to a preparation method for obeticholic acid and an intermediate thereof. The intermediate 3alpha-hydroxy-6alpha-ethyl-7-keto-5beta-cholanic acid is obtained by subjecting 3alpha-hydroxy-6-ethylidene-7-keto-5beta-cholanic acid benzyl ester compounds to a reaction under the action of a catalyst and a hydrogen donor. The catalyst is selected from Pd/C or PtO2 or Raney Ni. The hydrogen donor is selected from cyclohexene or cyclohexadiene or tetrahydronaphthalene. According to the method, the yield is high, the stereoselectivity is high, safety is good, the reaction condition is mild, and the method is applicable to industrial production.

The invention relates to chirality phosphine ligand metal complex catalyse system, which is composed by complex formed by ligand and metal Rh, Ru, Ir, Pt or Pd or ligand and metal precursor in of 1-2 mol ratio. The phosphine ligand is a kind of effective chirality phosphate ligand composed by D-mannitol or L-mannitol after reaction. The catalyst composed by the chirality ligand and rhodium metallic compound in asymmetry hydrogenation reaction can work in room temperature. With a wide applied range, catalyst's activation and stereoselectivity is not influenced from normal pressure to high pressure. Reaction time is 1-24 hours. Mol ratio of ligand and metal rhodium compound is 1:1-2:1. Ratio of reactant and catalyst is 100-10,000.

The invention specifically relates to an optical pure 1,3-alkamine compound as well as a preparation method and application thereof in preparing corresponding optical pure 1,3-alkamine and further preparing Dapoxetine and analogues thereof, belonging to the technical field of organic chemistry. The 1,3-alkamine compound is as shown in a formula I.

The invention provides a new strain-Trichoderma asperellum ZJPH0810, and an application thereof in microbial catalysis asymmetric synthesis of (R)-[3,5-dual (trifluoromethyl) phenyl] ethanol. The Trichoderma asperellum ZJPH0810 is preserved in the CCTCC, the address is Wuhan University, Wuhan Province, China, 430072 with the preservation date of 16th, December, 2009 and the preservation number of CCTCC No: M209307. The strain of the invention is used for the microbial asymmetric reduction of 1-[3,5-dual (trifluoromethyl) phenyl] ethanol to prepare the (R)-[3,5-dual (trifluoromethyl) phenyl] ethanol which has the advantages of high stereoselectivity, high optical purity and the like. When substrate concentration reaches 80 mmol/ L, yield can reach 53.4%. The invention screens and obtains new microbe strains different from the existing similar research reports, and can obtain the yield of (R)-[3,5-dual (trifluoromethyl) phenyl] ethanol product, which is higher than the yield reported by the document under the same substrate concentration, so that the invention provides a beneficial reference on the aspect of preparing the key chiral intermediates of Emend drugs with a microbiological method.