A kind of racemization method of chiral n-phenylacetyl amino acid and its derivatives

Abstract

The invention belongs to the field of amino acid racemization, and specifically discloses a racemization method of chiral N-phenylacetyl amino acid and its derivatives, comprising the following steps: heating phenylacetic acid to 160-180°C, and then adding chiral N-phenyl For acetyl amino acid or its derivatives, adjust the temperature to 150-160°C and keep it warm for 3-6 minutes, then lower the reaction temperature to 130-150°C and keep it warm for 10-30 minutes. After post-treatment, racemized N-phenylacetyl amino acid and its derivatives can be obtained . The invention has mild conditions, fast racemization speed and few side reactions, improves the yield of racemization products without increasing the cost, and can make the racemization more complete, and the used intermediates can be recycled, so it has low cost , high practical value, suitable for large-scale industrial production applications, and provides good technical support for the configuration inversion and resolution of chiral amino acids.

Description

technical field [0001] The invention relates to a racemization method for amino acids and derivatives thereof, in particular to a racemization method for chiral N-phenylacetyl amino acids and derivatives thereof. [0002] technical background [0003] Racemization is the process of converting one enantiomer of a single configuration into two enantiomers. Amino acid is an important chiral compound, which has two configurations of natural L-type and unnatural D-type. Under certain conditions, amino acids with a single configuration can be converted into DL-amino acids, which is the racemization of amino acids . L-amino acid is a natural amino acid, which plays an important role in the fields of medicine, food and chemical industry. As for D-amino acid, people thought it was useless in the early days. With the deepening of research, people gradually found that D-amino acid plays an important role in life activities and It plays an irreplaceable role in the preparation of drugs...

AI Technical Summary

Problems solved by technology

[0006] (1) U.S. Patent US3213106 discloses a method for racemization of amino acids. In a closed tube, 150-250 ° C and water are heated together to conduct racemization experiments on 12 kinds of amino acids. Most of the amino acids have different degrees of racemization, but Less degree of racemization and versatility

[0007] (2) Japanese patent JP 54003860 discloses a racemization method of N-acetyl amino acid. At 70°C, N-acetyl amino acid is heated with 2M NaOH for racemization. The yield of this method is not high but only 75%.

This method requires the simultaneous use of two enzymes, but it is difficult to be widely used due to the specificity and easy loss of activity of the enzymes.

[0009] (4) German patent DE1963991 discloses a racemization method of N-benzoyl amino acid derivatives. At 80°C, it is heated together with acetic anhydride for 45 minutes for racemization, but the racemization yield of this method is general and requires more consumption Acetic anhydride

[0010] At present, the racemization process of amino acids and their derivatives has high reaction energy consumption, harsh operating conditions, easy decomposition of amino acids and their derivatives, poor tolerance to functional groups of amino acids and their derivatives, prone to side reactions, and low racemization rate, etc. insufficient

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