67336-19-0Relevant articles and documents
Enzymatic synthesis of chiral phenylalanine derivatives by a dynamic kinetic resolution of corresponding amide and nitrile substrates with a multi-enzyme system
Yasukawa, Kazuyuki,Asano, Yasuhisa
, p. 3327 - 3332 (2013/01/15)
Mutant α-amino-ε-caprolactam (ACL) racemase (L19V/L78T) from Achromobacter obae with improved substrate specificity toward phenylalaninamide was obtained by directed evolution. The mutant ACL racemase and thermostable mutant D-amino acid amidase (DaaA) from Ochrobactrum anthropi SV3 co-expressed in Escherichia coli (pACLmut/pDBFB40) were utilized for synthesis of (R)-phenylalanine and non-natural (R)-phenylalanine derivatives (4-OH, 4-F, 3-F, and 2-F-Phe) by dynamic kinetic resolution (DKR). Recombinant E. coli with DaaA and mutant ACL racemase genes catalyzed the synthesis of (R)-phenylalanine with 84% yield and 99% ee from (RS)-phenylalaninamide (400 mM) in 22 h. (R)-Tyrosine and 4-fluoro-(R)-phenylalanine were also efficiently synthesized from the corresponding amide compounds. We also co-expresed two genes encoding mutant ACL racemase and L-amino acid amidase from Brevundimonas diminuta in E. coli and performed the efficient production of various (S)-phenylalanine derivatives. Moreover, 2-aminophenylpropionitrile was converted to (R)-phenylalanine by DKR using a combination of the non-stereoselective nitrile hydratase from recombinamt E. coli and mutant ACL racemase and DaaA from E. coli encoding mutant ACL racemase and DaaA genes. Copyright
Practical and convenient enzymatic synthesis of enantiopure α-amino acids and amides
Wang, Mei-Xiang,Lin, Shuang-Jun
, p. 6542 - 6545 (2007/10/03)
Catalyzed by the nitrile hydratase and the amidease in Rhodococcus sp. AJ270 cells under very mild conditions, a number of α-aryl- and α-alkyl-substituted DL-glycine nitriles 1 rapidly underwent a highly enantioselective hydrolysis to afford D-(-)-α-amino acid amides 2 and L-(+)-α-amino acids 3 in high yields with excellent enantiomeric excesses in most cases. The overall enantioselectivity of the biotransformations of nitriles originated from the combined effects of a high L-enantioselective amidase and a low enantioselective nitrile hydratase. The influence of the substrates on both reaction efficiency and enantioselectivity was also discussed in terms of steric and electronic effects. Coupled with chemical hydrolysis of D-(-)-α-phenylglycine amide, biotransformation of DL-phenylglycine nitrile was applied in practical scale to produce both D- and L-phenylglycines in high optical purity.
Highly efficient and enantioselective synthesis of L-arylglycines and D-arylglycine amides from biotransformations of nitriles
Wang, Mei-Xiang,Lin, Shuang-Jun
, p. 6925 - 6927 (2007/10/03)
Under very mild conditions, the Rhodococcus sp. AJ270-catalysed biotransformation of arylglycine nitriles 1, prepared easily from the reaction of substituted benzaldehydes, ammonium chloride and potassium cyanide, proceeded efficiently to produce optically active D-arylglycine amides 2 and L-arylglycines 3 in excellent yields with enantiomeric excesses higher than 99%.
Efficient chemoenzymatic synthesis of enantiomerically pure α-amino acids
Beller, Matthias,Eckert, Markus,Geissler, Holger,Napierski, Bernd,Rebenstock, Heinz-Peter,Holla, E. Wolfgang
, p. 935 - 941 (2007/10/03)
A general two-step chemoenzymatic synthesis for enantiomerically pure natural and nonnatural α-amino acids is presented. In the first step of the sequence, the ubiquitous educts aldehyde, amide and carbon monoxide react by palladium-catalyzed amidocarbonylation to afford the racemic N-acyl amino acids in excellent yields. In the second step, enzymatic enantioselective hydrolysis yields the free optically pure a-amino acid and the other enantiomer as the N-acyl derivative, both in optical purities of 85-99.5% ee. The advantage of the chemoenzymatic process compared to other amino acid synthesis are demonstrated by the preparation of various functionalized (-OR, -Cl, -F, -SR) α-amino acids on a 10-g scale.
Synthesis of Optically Active Arylglycines by Photolysis of Optically Active (β-Hydroxyamino) Carbene-Chromium(0) Complexes
Vernier, Jean-Michel,Hegedus, Louis S.,Miller, David B.
, p. 6914 - 6920 (2007/10/02)
Photolysis of chromium complexes having the optically active amino alcohol (1R,2S)-(-)- or (1S,2R)-(+)-2-amino-1,2-diphenylethanol as the amino group produced aryl-substituted oxazinones in good yield with reasonable diastereoselectivity.Facile separation of diastereoisomers followed by mild reductive cleavage produced several arylglycines, having either electron-donating or withdrawing groups on the aromatic ring, in good overall yield and with excellent enantiomeric excess.
Stereoselective synthesis of L-amino acids via Strecker and Ugi reactions on carbohydrate templates
Kunz,Pfrengle,Ruck,Sager
, p. 1039 - 1042 (2007/10/02)
L-Amino acid derivatives are stereoselectively synthesized in high yield using 2,3,4-tri-O-pivaloyl-α-D-arabinopyranosylamine or 2,3,4-tri-O-pivaloyl-β-L-fucopyranosylamine as the chiral auxiliary in Strecker and Ugi reactions.
CARBOHYDRATES AS CHIRAL TEMPLATES: DIASTEREOSELECTIVE UGI SYNTHESIS OF (S)-AMINO ACIDS USING O-ACYLATED D-ARABINOPYRANOSYLAMINE AS THE AUXILIARY
Kunz, Horst,Pfrengle, Waldemar,Sager, Wilfried
, p. 4109 - 4110 (2007/10/02)
Enantiomerically pure (S)-amino acids are synthesized via a highly diastereoselective Ugi reaction using 2,3,4-tri-O-pivaloyl-α-D-arabinopyranosylamine as the chiral template.
ASYMMETRIC INDUCTIVE SYNTHESIS OF α-AMINOARYLACETIC ACIDS IN CHIRAL MICELLAR SYSTEM
Zhang, Yongmin,Li, Weixing
, p. 1685 - 1690 (2007/10/02)
In the micellar solution of chiral surfactant N-hexadecyl-N-methylephedrine bromide, seven α-aminoarylacetic acids were synthesized from corresponding aldehydes, the e.e.percent being about 28percent.
