Biotransformation method for L-tert-leucine

Abstract

The invention discloses a biotransformation method for L-tert-leucine. The method includes the following steps: establishing a transformation system by utilizing sodium trimethylpyruvate as a substrate, utilizing coenzyme NAD+ and immobilized leucine dehydrogenase and formate dehydrogenase as a biocatalyst and by adding an ammonium salt; and performing a biotransformation reaction to obtain a transformation liquid containing the L-tert-leucine. The biotransformation method utilizes the immobilized leucine dehydrogenase and formate dehydrogenase as the biocatalyst which can still have enzyme activity after ten times of reuse, and an expensive coenzyme and enzyme can be recycled, so that the production cost is saved; a self-made sodium trimethylpyruvate solution is utilized as the substrate,so that the preparation process is simplified, the production cost is saved, and purification is convenient; and the purity of a prepared L-tert-leucine crystal reaches 98.5% or above, and the optical purity is 99% or above. Process flow is simple, no special requirements are for equipment, and industrialization production is suitable. HPLC-MS and HPLC are utilized to monitor until the substrateis completely utilized.

Description

technical field [0001] The invention relates to a preparation method of unnatural amino acid, in particular to a biotransformation method of L-tert-leucine. Background technique [0002] Unnatural amino acids and their derivatives are important chemical intermediates. Among them, L-tert-leucine is an important unnatural amino acid, which can be used to synthesize pharmaceutical intermediates, and as a chiral inducer for asymmetric synthesis and unnatural A resolution reagent for symmetrical resolution, widely used in the synthesis of biological inhibitors, bioactive peptides, anticancer and antiviral drugs. At present, the protease inhibitor anti-HIV new drugs listed by pharmaceutical companies such as Bristol-Myers Squibb, Pfizer, and Abbott all use L-tertiary leucine as an intermediate, such as the anti-HIV drug Atazanavir (Atazanavir), its global sales in 2006 In addition, six new anti-HIV and anti-tumor drugs in clinical trials also use L-tert-leucine as an intermediate...

AI Technical Summary

Problems solved by technology

Several patent applications have been disclosed for this route, and the main problems of its existence are: in the currently disclosed patents, the initial substrate concentration of the reaction is 10-15%, and L-tert-leucine dehydrogenase has a high substrate concentration. It will be significantly inhibited by the substrate, and the reaction rate will drop sharply. Under the condition of high ammonia concentration, the excess substrate and the product accumulation will form by-products, indicating that the method is difficult to repeat.

In addition, the dosage of the enzyme is too much, the dosage of the expensive coenzyme NAD reaches 1% (w / w) of the substrate, the economy is poor, and there is no clear post-extraction process, which still cannot meet the needs of industrial production

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