The present invention relates to a method for preparing pregabalin by a biological enzyme method. In particular, the method comprises producing pregabalin B and an R-configuration compound C by using a compound A as a raw material under the action of a biological enzyme; performing configuration inversion of the separated and recovered R-configuration compound C under the action of an isomerase to produce an S-configuration compound D; and producing pregabalin B from the compound D under the action of a biological enzyme

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The present invention relates to a bifunctional chiral organocatalytic compound having excellent enantioselectivity, a preparation method therefor, and a method for producing a non-natural gamma amino acid from a nitro compound by using the chiral organocatalytic compound. According to the present invention, the bifunctional chiral organocatalytic compound having excellent enantioselectivity can be easily synthesized, gamma-amino acids with high optical selectivity can be obtained at a high yield by an economical and convenient method using the chiral organocatalytic compound, and various (R)-configuration gamma-amino acids, which are not present in nature, can be produced with high optical purity in large quantities by using a small amount of a catalyst, and therefore, the present invention can be widely utilized in various industrial fields including the pharmaceutical industry.

The present invention relates to a bifunctional chiral organocatalytic compound having excellent enantioselectivity, a preparation method therefor, and a method for producing a non-natural gamma amino acid from a nitro compound by using the chiral organocatalytic compound. According to the present invention, the bifunctional chiral organocatalytic compound having excellent enantioselectivity can be easily synthesized, gamma-amino acids with high optical selectivity can be obtained at a high yield by an economical and convenient method using the chiral organocatalytic compound, and various (R)-configuration gamma-amino acids, which are not present in nature, can be produced with high optical purity in large quantities by using a small amount of a catalyst, and therefore, the present invention can be widely utilized in various industrial fields including the pharmaceutical industry.

Provided herein are processes, compounds and compositions for making (S)-3-amino-4-(difluoromethylenyl)cyclopent-1-ene-1-carboxylic acid. Also provided herein a pharmaceutical compositions containing (S)-3-amino-4-(difluoromethylenyl)cyclopent-1-ene-1-carboxylic acid.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-5 dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-5 dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.

The present invention relates to a process for synthesis of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol abbreviated THIP, having the INN name gaboxadol, starting from pyrrolidin-2-one. The process comprises a new direct process to obtain the intermediate dimethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-5 dicarboxylate or the intermediate diethyl 5-hydroxy-3,6-dihydropyridine-1,4(2H)-dicarboxylate.