5results about How to "High ee value" patented technology

The application discloses a kind of photocontrol chiral ligand based on diarylethene, structural general formula is as shown in following formula:After the photocontrol chiral ligand based on diarylethene synthesized in the application and rhodium catalyst coordination, when catalyzing asymmetric carbon hydrogen amidation at room temperature, higher reaction yield and higher ee value can be obtained by using ligand in open loop state to catalyze, and lower reaction yield and lower ee value can be obtained by using ligand in light stable state to catalyze.The application makes up the deficiency that there is currently lack of photo-thermal bistable photocontrol catalyst in the field of photocontrol asymmetric catalysis, and widens the application of diarylethene in photocontrol asymmetric catalysis.

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.

This invention discloses a reductase mutant and its application in the preparation of S-Bosein. The reductase mutant differs from the amino acid sequence shown in SEQ ID NO:3 in containing one or more amino acid residues at sites Q95, L96, and G190. The reductase mutant of this invention exhibits high substrate conversion and high ee value of S-Bosein when using β-pyruvate as a substrate, making it suitable for industrial production.

The invention relates to a method for preparing (R)-salbutamol. Specifically, L-threonine and a compound 1 are taken as raw materials, a compound 2 is formed under the catalysis of L-threonine transaldolase, the compound 2 is formed into a compound 3 under the catalysis of decarboxylase, on the basis, the compound 3 is taken as a substrate, and the (R)-salbutamol is further synthesized. And the method has the characteristics of low cost of raw materials and auxiliary materials, short process steps, simplicity and convenience in operation, mild reaction conditions and environmental friendliness.

The invention belongs to the technical field of chemical synthesis, and relates to a method for synthesizing a chiral alpha-non-natural aromatic amino acid derivative under visible light driving. The preparation method comprises the following steps: carrying out in-situ matching on a compound 1 and a ligand under the action of a catalyst, and then continuously carrying out photocatalytic coupling reaction on the compound 1 and a compound 2 under the action of an additive to obtain a compound 3, namely the chiral alpha-non-natural aromatic amino acid derivative. Rich types of natural carboxylic acids exist in the nature, redox active ester derived from aromatic acetic acid is adopted as an aryl donor, a guarantee is provided for structural diversity synthesis of chiral alpha-non-natural aromatic amino acid, a non-natural amino acid compound library can be enriched to a great extent, and assistance is provided for development of polypeptide innovative drugs.