46results about How to "High chiral selectivity" patented technology

The invention relates to a platinum/carbon nanotube catalyst suitable for multiphase asymmetric hydrogenation reaction. Platinum is loaded on a carbon nanotube carrier. A preparation method comprises the following steps of: heating a purified carbon nanotube in nitric acid, washing, filtering, washing by using water until the pH value of filtrate is neutral, drying to obtain the carbon nanotube carrier, soaking in aqueous solution of chloroplatinic acid, and performing ultrasonic treatment at room temperature; and stirring and impregnating a mixture of the carbon nanotube and the aqueous solution of chloroplatinic acid, raising the temperature to 110 DEG C from room temperature, drying at the temperature of 110 DEG C, grinding into fine powder, reducing by using aqueous solution of sodiumformate with heating, filtering, washing by using deionized water and drying. The invention also provides the preparation method of the catalyst and application of the catalyst to the multiphase asymmetric hydrogenation reaction.

The invention discloses threonine aldolase, a mutant, encoding genes of the threonine aldolase and the mutant, a recombinant vector constructed by the encoding genes, recombinant genetic engineering strains obtained by transforming the recombinant vector and application of the threonine aldolase and the mutant in preparation of 2-/3-/4-substituted phenylserine derivatives. The threonine aldolase and the mutant serve as biocatalysts, and 2-/3-/4-substituted benzaldehyde serves as a substrate, 5-pyridoxal phosphate serves as coenzyme, glycine/glycine ester serves as an auxiliary substrate, and enzymic catalytic reaction is performed in a medium under appropriate conditions to separate and prepare a series of phenylserine derivatives with different substituents. According to the method, the total yield ranges from 76% to 99%, and the ee value of the product is greater than 99%, and the de value ranges from 70% to 99%.

The invention discloses an intelligent graphene nano-material with high chiral selectivity as well as preparation and application thereof. The material is prepared from graphene, a temperature-sensitive component, a magnetic component and the like. The material disclosed by the invention has high chiral selectivity, temperature-sensitive performance and magnetic responsiveness; the material has the advantages of simplicity in operation, high resolution efficiency, convenience for recycling materials, and environment-friendly operation process in chiral resolution of an amino acid enantiomer, and has a good industrial application prospect.

The invention relates to a method for preparing a nebivolol midbody, which belongs to the technical field of medicament synthesis, for solving the problems that the conventional raw material is high in cost, long in route and low in yield. The method comprises the following steps: enabling 6-fluorine chroman-2-formic acid as a raw material to react with chloro-carbonic ester with the presence of a deacid reagent, then adding diazomethane after the reaction is accomplished, so as to enable the midbody to react with the diazomethane to generate a reaction liquid of an intermediate product, and then adding a hydrogen halide gas or a hydrogen halide solution into the reaction liquid to perform halogenating reaction so as to obtain a compound of formula IV, namely, (6-(fluorine-3,4-dihydro-2H-benzopyran-2-methanol-2-yl) ethanone halogenate. The method provided by the invention has the advantages that the reaction route is short, the yield is high, and the used material is low in price and easy to purchase.

The invention relates to a new pattern agent for separating amino acid enantiomer, which belongs to the mass transfer isolation technique field about chemical industry, chemical and medicine. The invention discloses the new pattern agent to solve the problem which both the low selective and small flux of chiral selectors hinder the chirality enantiomer drugs industrial mass production seriously, which comprises: mixing the chirality molecule D-dimethylbenzoyl tartaric acid or L-dimethylbenzoyl tartaric acid with the mole ratio as 1:1-40 and D2EHPA, adding octanol as deflocculating agents, and stirring to get the D-dimethylbenzoyl tartaric acid, L-dimethylbenzoyl tartaric acid or D2EHPA with unreactive chiral molecules and the mixture liquid system of intermediate complex compound from the reaction formation. The mixture liquid system is the said new pattern agent for separating amino acid enantiomer.

The invention discloses a biological preparation method of (S)-1-(2-iodine-5-fluorophenyl) ethanol. The biological preparation method comprises the following steps: taking a certain concentration of prochiral ketone 2'-iodine-5'-fluoroacetophenone as a substrate, adding a certain amount of genetically engineered bacteria, at the temperature of 20 to 50 DEG C, reacting in a reaction system converted by a buffer solution with the pH of 5.5 to 10.5, and after the reaction is completed, separating and purifying a reaction solution to obtain a corresponding product, wherein the genetically engineered bacteria are genetically engineered bacteria containing a carbonyl reductase EbSDR8 mutant encoding gene; and the nucleotide sequence of the carbonyl reductase EbSDR8 mutant encoding gene is SEQ IDNO.3. The method is mild in reaction condition, high in substrate adaptation and environmentally-friendly, and reconstitution cells of the enzyme can be used for efficiently catalyzing asymmetric reduction of high-concentration prochiral ketone in an isopropanol-containing reaction system without adding any coenzyme, so that generated chiral alcohol (ee being greater than or equal to 99%) with high optical purity has an excellent industrialized application prospect.

The invention provides an L-cyclic alkylamino acid synthesis method and a medicinal composition containing L-cyclic alkylamino acid. The synthesis method comprises the following steps: 1, preparing cyclic alkyl ketonic acid or cyclic alkyl ketonate having a structure represented by formula (I) or formula (II); and 2, mixing the cyclic alkyl ketonic acid or cyclic alkyl ketonate with ammonium formate, a leucine dehydrogenase, a formate dehydrogenase and a coenzyme NAD<+>, and carrying out a reduction amination reaction to generate the L-cyclic alkylamino acid, wherein n1 in the formula (I) is not lower than 1, m1 in the formula is not lower than 0, and M1 is H or a univalent cation; n2 in the formula (II) is not lower than 0, m2 in the formula (II) is not lower than 0, and M2 is H or a univalent cation; and the amino acid sequence of the leucine dehydrogenase is represented by SEQ ID No.1. The method utilizes specific leucine dehydrogenase, the formate dehydrogenase and the coenzyme NAD<+> to carry out the reduction amination reaction of the cyclic alkyl ketonic acid or cyclic alkyl ketonate, and has a high raw material conversion rate and a high chiral selectivity.

The invention relates to the technical field of medical intermediates, specifically to a transaminase catalyst and a method for enzymatic synthesis of (R)-1-naphthylethylamine. The method comprises the following steps: adding recombinant escherichia coli wet thalli expressing the transaminase catalyst and 1-acetophenone into a reaction container, carrying out heating in a water bath, and carryingout mechanical stirring; adding an organic solvent or an aqueous solution of water, an amino donor and pyridoxal phosphate under stirring; and after a reaction is finished, carrying out post-treatmentso as to obtain the (R)-1-naphthylethylamine. The transaminase catalyst disclosed by the invention is easy to obtain and high in chiral selectivity; meanwhile, the method for enzymatic synthesis of the (R)-1-naphthylethylamine is simple in operation, mild in reaction conditions and stable in reaction completion, and can directly generate the (R)-1-naphthylethylamine with an optical purity of 99%or above, so tedious chemical resolution steps and a tedious chemical reaction route are avoided.

The invention provides a synthetic method of L-heterocyclic amino acid and a pharmaceutical composition with L-heterocyclic amino acid. The synthetic method comprises the steps that A, heterocyclic ketonic acid is prepared, wherein heterocycle in heterocyclic ketonic acid is selected from any one of pentabasic single heterocycle, hexabasic single heterocycle, heptabasic single heterocycle, pentabasic alkylation single heterocycle, hexabasic alkylation single heterocycle and heptabasic alkylation single heterocycle, and a structural formula of ketonic acid base in heterocyclic ketonic acid is as shown in the specification, and is positioned in any carbon position of heterocycle; and B, heterocyclic ketonic acid is mixed with ammonium formate, phenylalanine dehydrogenase, formate dehydrogenase and coenzyme NAD<+> to perform a reduced amination reaction to generate L-heterocyclic amino acid, wherein an amino acid sequence of phenylalanine dehydrogenase is SEQ ID No. 1 (sequence identifier number 1). Since special phenylalanine dehydrogenase, formate dehydrogenase and coenzyme NAD<+> are used for allowing heterocyclic ketonic acid to perform the reduced amination reaction to generate L-heterocyclic amino acid, the raw material conversion rate is high and the chiral selectivity is high.

The invention discloses a preparation method of a high-purity capecitabine key intermediate. The preparation method comprises the following steps: taking D-ribose as an initial raw material, performing hydroxyl protection, 5-site tosylation, reduction, deprotection and acetylation to obtain high-purity 1,2,3-O-triacetyl-5-deoxo-D-ribose, wherein the 5-site tosylation reaction is carried out in anorganic solvent 1 by adopting inorganic base 1. Meanwhile, the acetylation reaction is carried in the presence of alkali 2 by taking water as a reaction solvent and taking 4-dimethylamiopryidine as acatalyst. The preparation method disclosed by the invention is mild in reaction conditions, high in yield, economic and effective, the purity of the prepared 1,2,3-O-triacetyl-5-deoxo-D-ribose can reach 99.0%, the alpha-isomer is small in content even is not detected, and the preparation method is applicable to large-scale industrial production.

The invention discloses a preparation method of a compound with a general formula I or pharmaceutically acceptable salts, stereoisomers, esters, prodrugs and solvates thereof, which comprises the following steps: (1) by using a compound A and (1S, 4R) 1methyl 4 (1methyl vinyl) 2cyclohexene 1alcohol as raw materials, carrying out coupling under the action of a chiral imidazolone salt catalyst to obtain a compound B; carrying out sodium sulfite dehalogenation and alkali washing to obtain an intermediate 1; (2) heating the intermediate 1 to 80100 DEG C under the action of DMSO, lithium chloride and an antioxidant, reacting, and recrystallizing to obtain a compound with a general formula I;.

The invention relates to a preparation method of 2-deoxy-2, 2-difluoro-D-red-3, 5-dibenzoate and belongs to the technical field of medicine intermediate synthesis. In order to solve the problems of poor selectivity and safety in the prior art, the invention provides the preparation method of the 2-deoxy-2, 2-difluoro-D-red-3, 5-dibenzoate, which comprises carrying out redox reaction on 2-deoxy-2,2-difluoro-D-red-1-ketofuranose-3, 5- dibenzoate under the combined action of immobilized catalysts of sodium borohydride and PPO-CBS to convert to the product of 2-deoxy-2, 2-difluoro-D-red-3, 5-dibenzoate. The method has the advantage of high chiral selectivity, improves the integral conversion rate, plays a better asymmetric reduction role, and achieves the purpose that the purity of the isomer is more than 95%.

The invention relates to the field of medicine preparation, in particular to a synthetic method of dehydroprogesterone, The synthetic method comprises the following steps: by using an A-ring degradation product as a raw material, carrying out addition reaction, dehydroxylation reaction, bromination reaction, elimination reaction, Grignard reaction, Mitsunobu reaction, twice Robinson ring-increasing reaction and water addition rearrangement reaction to generate a dehydroprogesterone product. The method has the advantages of cheap and easily available initial raw materials, few isomer impuritiesin the reaction process, easy purification, high product yield and the like, and has the advantages of short steps, simple operation, low equipment requirements, simple and easily available reagentsand easy realization of industrial production.

The invention relates to application of aC=C bond connection-based COF material in preparation of a chiral chromatographic stationary phase. The preparation method comprises the following steps: synthesizing chiral COF connected with a C=C bond by using a crown ether functionalized dinaphthalene tetraaldehyde monomer on the basis of a Knoevenagel condensation reaction; compounding COF and silica gel by using a net package method to prepare a high performance liquid chromatography chiral stationary phase; uniformly coating COF on a gas chromatographic column by using a dynamic coating method so as to be used as a gas chromatographic chiral stationary phase; and applying the high performance liquid chromatographic column or gas chromatographic column to separate various racemic compounds. Compared with the prior art, due to the high stability of the synthesized C=C bond connection COF, the liquid chromatographic column and the gas chromatographic column prepared in the invention both show good separation capability and durability in the chiral separation process, so that the problem that the existing chiral stationary phase is only suitable for a specific chromatography is solved, a novel high-performance chiral separation material which can be used for liquid chromatography and gas chromatography at the same time is developed, and potential application prospects are achieved.

The invention provides omega transaminase as well as a mutant, a recombinant plasmid, a genetically engineered bacterium and application thereof. The amino acid sequence of the omega transaminase is shown as SEQ ID No: 2, wherein the omega transaminase mutant is obtained by mutation of the amino acid sequence of the omega transaminase and has at least 90% of homology with the SEQ ID No: 2. According to the invention, the omega transaminase gene is extracted from Burkholderia phymatum, the heterologous expression of the omega transaminase gene is realized, and the generated omega transaminase strain shows excellent catalytic activity on a series of aryl alkyl substrates. The omega transaminase is mutated to obtain a series of omega transaminase mutants, and the omega transaminase mutants are coupled with different enzymes to be applied to the production of asymmetric synthesis of (S)-1-amphetamine and other chiral amine products by a biological enzyme method, so that the method has thecharacteristics of economy, environmental protection and high chiral selectivity; thus, the invention provides a potential choice for industrial application of transaminase.

The invention discloses a synthesis process of an S-(-)-nadifloxacin chiral intermediate, and belongs to the technical field of chemical pharmacy. The synthesis process comprises the following steps: 1, synthesizing an intermediate 1; and 2, synthesizing the S-(-)-chiral intermediate. R binaphthylenediamine is used as a matrix of a chiral ligand, epoxy polysilsesquioxane is grafted on a molecule of N-Boc-L-histidine to form the chiral ligand, on one hand, the ee value is increased by utilizing the chiral characteristic of N-Boc-L-histidine, and on the other hand, the ee value is increased by utilizing the characteristics of nanoscale size and solubility of the epoxy polysilsesquioxane, so that the solubility of the catalyst is increased, and the catalyst can be mixed with the reactant in the nanometer size so as to improve the catalytic performance of the chiral catalyst and improve the reaction yield, such that the chiral ligand and the metal ruthenium are subjected to coordination to form the chiral catalyst so as to provide the good chiral amplification effect;.

The invention discloses a (2m, m) carbon nano tube horizontal array and a preparation method thereof. The preparation method includes the following steps that ammonium salts are transferred to a base,then annealing treatment is carried out, and the ammonium salts are ammonium molybdate or tungstic acid ammonium; reduction of the ammonium salts is performed by using hydrogen; and carbon source gasis injected into a reaction vessel for growth after the reduction step is completed, and the (2m, m) carbon nano tube horizontal array is obtained. According to the (2m, m) carbon nano tube horizontal array, the diameter of a carbon nano tube is 0.7-1.3 nm and the length of the carbon nano tube is 100-300 [mu]m; a catalyst used in the (2m, m) carbon nano tube horizontal array is carbide which hashigher catalytic activity and the activity of the carbide is higher than an existing metal catalyst, and that is the key to obtain the carbon nano tube with higher density; the melting point of catalyst molybdenum carbide used in the (2m, m) carbon nano tube horizontal array is high and a solid form can be maintained, so that the carbon nano tube with extremely high chiral selectivity can be obtained; the single-crystal base is used as the growth base, since the single-crystal base has double symmetry, the carbon nano tube obtained by the growth has high arrayability.