86169-24-6Relevant articles and documents
Method for continuously and quickly preparing DL-phenylglycine and analogue thereof
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Paragraph 0031-0033, (2019/07/04)
The invention provides a method for continuously and quickly preparing DL-phenylglycine and an analogue thereof. The method comprises the steps of adding 2-hydroxyl-phenylacetonitrile and an analoguethereof (cyanohydrin for short) and an aqueous ammonium bicarbonate solution into a microchannel reactor for a reaction, controlling the reaction temperature to be 80-130 DEG C, and controlling the reaction pressure to be 0.5-2.0 MPa, wherein the standing time of the reactants in a microchannel is 1-8 min, and an aqueous solution of 5-phenyl-hydantoin and an analogue thereof (hydantoin for short)is obtained; adding the hydantoin and alkali into the microchannel reactor for a reaction, controlling the reaction temperature to be 120-200 DEG C, and controlling the reaction pressure to be 1.0-3.5MPa, wherein the standing time of the reactants in the microchannel is 1-8 min, and then a saline solution of phenylglycine and an analogue thereof is obtained; conducting acidification neutralization and crystallization to obtain the phenylglycine and the analogue thereof. According to the method, the microchannel reactor is adopted, the reaction time is greatly shorted, the reaction speed is increased, pyrolysis and polymerization of the cyanohydrin are reduced, no by-products are generated, the products are high in yield, clean and environmentally friendly, and the production cost is lowered.
One-Pot Enantioselective Synthesis of d-Phenylglycines from Racemic Mandelic Acids, Styrenes, or Biobased l-Phenylalanine via Cascade Biocatalysis
Zhou, Yi,Wu, Shuke,Li, Zhi
supporting information, p. 4305 - 4316 (2017/11/21)
Enantiopure d-phenylglycine and its derivatives are an important group of chiral amino acids with broad applications in thepharmaceutical industry. However, the existing synthetic methods for d-phenylglycine mainly rely on toxic cyanide chemistry and multistep processes. To provide green and safe alternatives, we envisaged cascade biocatalysis for the one-pot synthesis of d-phenylglycine from racemic mandelic acid, styrene, and biobased l-phenylalanine, respectively. Recombinant Escherichia coli (LZ110) was engineered to coexpress four enzymes to catalyze a 3-step reaction in one pot, transforming mandelic acid (210 mM) to give enantiopure d-phenylglycine in 29.5 g L?1 (195 mM) with 93% conversion. Using the same whole-cell catalyst, twelve other d-phenylglycine derivatives were also produced from the corresponding mandelic acid derivatives in high conversion (58–94%) and very high ee (93–99%). E. coli (LZ116) expressing seven enzymes was constructed for the transformation of styrene to enantiopure d-phenylglycine in 80% conversion via a one-pot 6-step cascade biotransformation. Twelve substituted d-phenylglycines were also produced from the corresponding styrene derivatives in high conversion (45–90%) and very high ee (92–99%) via the same cascade reactions. A nine-enzymeexpressing E. coli (LZ143) was engineered to transform biobased l-phenylalanine to enantiopure d-phenylglycine in 83% conversion via a one-pot 8-step transformation. Preparative biotransformations were also demonstrated. The high-yielding synthetic methods use cheap and green reagents (ammonia, glucose, and/or oxygen), and E. coli whole-cell catalysts, thus providing green and useful alternative methods for manufacturing d-phenylglycine. (Figure presented.).
Chemo-enzymatic approach to the synthesis of the antithrombotic clopidogrel
Ferraboschi, Patrizia,Mieri, Maria De,Galimberti, Fiorella
scheme or table, p. 2136 - 2141 (2010/10/03)
The (S)-2-chlorophenylglycine moiety is well recognized in the structure of (S)-clopidogrel, a known antithrombotic drug. We prepared an enantiomerically pure chiral building block via an enzyme-catalyzed resolution of (RS)-N-Boc-2-chlorophenylglycine methylester. The best results were obtained by means of an immobilized subtilisin, the cross-linked enzyme aggregate (Alcalase-CLEA). The high enantiomeric excess of the synthon obtained remained the same over the course of clopidogrel synthesis; the simplicity of the process makes this pathway suitable for large-scale preparation.
