Abstract: Provided is a method for preparing rebaudioside M by using an enzyme method. In the method, rebaudioside A or rebaudioside D is used as a substrate; and in the existence of a glucosyl donor, rebaudioside M is generated by means of reaction of the substrate under the catalysis of UDP-glucosyl transferase and/or recombinant cells containing the UDP-glucosyl transferase.

Abstract: Provided is a method for preparing rebaudioside M by using an enzyme method. In the method, rebaudioside A or rebaudioside D is used as a substrate; and in the existence of a glucosyl donor, rebaudioside M is generated by means of reaction of the substrate under the catalysis of UDP-glucosyl transferase and/or recombinant cells containing the UDP-glucosyl transferase.

Abstract: Provided is a method for preparing rebaudioside M by using an enzyme method. In the method, rebaudioside A or rebaudioside D is used as a substrate; and in the existence of a glucosyl donor, rebaudioside M is generated by means of reaction of the substrate under the catalysis of UDP-glucosyl transferase and/or recombinant cells containing the UDP-glucosyl transferase.

Abstract: Provided in the present invention is a method for preparing rebaudioside M by using an enzymatic process, which catalyzes the formation of rebaudioside M using a recombinant Saccharomyces cerevisiae containing a UDP-glucosyltransferase or a UDP-glucosyltransferase prepared therefrom. The recombinant Saccharomyces cerevisiae is obtained by transforming an expression vector containing the UDP-glucosyltransferase gene under the control of a strong promoter.

Abstract: Provided is a method for preparing Rebaudioside M by using an enzyme method. In the method, Rebaudioside A or Rebaudioside D is used as a substrate, and in the presence of sucrose and UDP, Rebaudioside M is generated by means of reaction of the substrate under the catalysis of a mixture of UDP-glucosyl transferase and sucrose synthetase, or recombinant cells containing the UDP-glucosyl transferase and sucrose synthetase. The reaction is carried out in an aqueous-phase system at a temperature of 20 to 60° C. and pH 5.0 to 9.0. The reaction system further contains dimethyl sulfoxide at a concentration of 3% to 5% according to the ratio by volume for facilitating solubilization of the substrate.

Abstract: Provided is a method for preparing rebaudioside M by using an enzyme method. In the method, rebaudioside A or rebaudioside D is used as a substrate; and in the existence of a glucosyl donor, rebaudioside M is generated by means of reaction of the substrate under the catalysis of UDP-glucosyl transferase and/or recombinant cells containing the UDP-glucosyl transferase.

Abstract: The invention discloses a new amino-quinazoline derivative and its use in preparing drugs for preventing and/or treating malignancies. The amino-quinazoline derivative of the invention is an ideal, high effective, dual and irreversible EGFR and HER2 kinase inhibitor, and can treat or prevent various malignancy diseases, such as breast cancer, ovarian cancer, gastrointestinal cancer, oesophageal cancer, lung cancer, head and neck squamous cancer, pancreatic cancer, epidermis squamous cell cancer, prostatic cancer, neuroglioma and nasopharynx cancer.

Abstract: Materials and methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: Materials and methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: Materials and methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: Materials and methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: Materials and Methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: Materials and Methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: The invention relates to biocatalytic methods for preparing enantiomerically pure stereoisomers of 1-(2,6-dichloro-3-fluorophenyl)ethanol. Disclosed are methods of preparation of the desired (S)-enantiomer, which methods are based on a combination of enzymatic resolution, chemical esterification and chemical hydrolysis with inversion of 1-(2,6-dichloro-3-fluorophenyl)ethyl esters or stereoselective bio-reduction of 2,6-dichloro-3-fluoro-acetophenone with a biocatalyst such as an enzyme or a microorganism. The chiral (S)-enantiomer can be used in the synthesis of certain enantiomerically enriched, ether linked 2-aminopyridine compounds that potently inhibit auto-phosphorylation of human heptocyte growth factor receptor.

Abstract: The invention relates to biocatalytic methods for preparing enantiomerically pure stereoisomers of 1-(2,6-dichloro-3-fluorophenyl)ethanol. Disclosed are methods of preparation of the desired (S)-enantiomer, which methods are based on a combination of enzymatic resolution, chemical esterification and chemical hydrolysis with inversion of 1-(2,6-dichloro-3-fluorophenyl)ethyl esters or stereoselective bio-reduction of 2,6-dichloro-3-fluoro-acetophenone with a biocatalyst such as an enzyme or a microorganism. The chiral (S)-enantiomer can be used in the synthesis of certain enantiomerically enriched, ether linked 2-aminopyridine compounds that potently inhibit auto-phosphorylation of human heptocyte growth factor receptor.

Abstract: Materials and methods for preparing (S)-(+)-3-aminomethyl-5-methyl-hexanoic acid and structurally related compounds via enzymatic kinetic resolution are disclosed.

Abstract: The present invention relates to methods of preparing a stereoisomerically enriched compound of formula (I), wherein R6 is hydrogen, comprising treating a compound of formula (I), wherein R6 is chosen from C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, —(CR7R8)t(C6-C14 aryl), and —(CR7R8)t(4-10 membered heterocyclic), and wherein said C6-C14 aryl and 4-10 membered heterocyclic are optionally substituted with at least one substituent chosen from halo, C1-C10 alkyl, —OR7, and —N(R7R8), with a biocatalyst in an aqueous solution, an organic solvent, or a mixture of organic and aqueous solvents wherein at least one stereoisomer is selectively hydrolyzed.

Abstract: The present invention provides a method for producing metabolites of capravirine (2-carbamoyloxymethyl-5-(3,5-dichlorophenyl)thio-4-isopropyl-1-(4-pyridyl)methyl-1H-imidazole) via whole cell biotransformation using fungi and bacterial cells as oxygenation catalysts.

Abstract: Efficient synthetic routes for the preparation of rhinovirus protease inhibitors of formula I, as well as key intermediates useful in those synthetic routes. These compounds of formula I, as well as pharmaceutical compositions that contain these compounds, are suitable for treating patients or hosts infected with one or more picornaviruses.

Abstract: Efficient synthetic routes for the preparation of rhinovirus protease inhibitors of formula I, key intermediates useful in those synthetic routes, as well as a continuous membrane reactor useful for those synthetic routes. These compounds of formula I, as well as pharmaceutical compositions that contain these compounds, are suitable for treating patients or hosts infected with one or more picornaviruses.