A novel process for the preparation of L-threo-dihydroxyphenylserine (Droxidopa) is described. It comprises of enantioselective hydrolysis of racemic (DL)-threo-N-acetyl-3-(3,4-methylenedioxyphenyl)-serine using commercially available L-amino acylase from Aspergillus sp. (EC 3.5.1.14) in the presence of cobalt ions, to obtain (L)-threo-3-(3,4-methylenedioxyphenyl)-serine followed by dealkylation to obtain Droxidopa. Protecting the amino group of (L)-threo-3-(3,4-methylenedioxyphenyl)-serine using either benzyloxycarbonyl or phthaloyl group before dealkylation followed by deprotection of the amino group results in obtaining Droxidopa in high yields and purity.

Disclosed are methods for producing optically active amino acids and amines. According to the methods, α-keto acids are generated as reaction intermediates, and as a result, ω-transaminase-catalyzed kinetic resolution of racemic amino acids or amines as racemic amine compounds enables the production of optically active amine compounds without the need to use expensive α-keto acids as starting materials. Therefore, the optically active amine compounds are produced at greatly reduced costs. In addition, the optically active amine compounds have high enantiomeric excess.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present invention is directed to a process for the enantioselective biocatalytic preparation of 4-substituted 1-aminoindanes of general formula (S)-I: (1) and a process for the preparation of Ozanimod, preferably involving the enantioselective biocatalytic process of preparing (S)-4-substituted 1-aminoindanes of the above general formula, wherein R=—CN and Y=H.

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The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

A novel process for the preparation of L-threo-dihydroxyphenylserine (Droxidopa) is described. It comprises of enantioselective hydrolysis of racemic (DL)-threo-N-acetyl-3-(3,4-methylenedioxyphenyl)-serine using commercially available L-amino acylase from Aspergillus sp. (EC 3.5.1.14) in the presence of cobalt ions, to obtain (L)-threo-3-(3,4-methylenedioxyphenyl)-serine followed by dealkylation to obtain Droxidopa. Protecting the amino group of (L)-threo-3-(3,4-methylenedioxyphenyl)-serine using either benzyloxycarbonyl or phthaloyl group before dealkylation followed by deprotection of the amino group results in obtaining Droxidopa in high yields and purity.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present invention provides a process for the preparation of lacosamide in substantially optically pure form, which in one aspect comprises the following steps: (i) resolution of O-methyl-D,L-serine to provide O-methyl-D-serine in substantially optically pure form; (ii) acetylation of O-methyl-D-serine thereby obtained to provide the N-acetyl 10 derivative thereof in substantially optically pure form; (iii) activating the carboxy group of the compound thereby obtained; and (iv) reacting the compound thereby obtained with benzylamine.