• Archives of Pharmacal Research
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• v.9 no.1
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• pp.45-47
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• 1986

Phenylglycine was obtained as the sole metabolite when .alpha.-aminophenylacetonitrile was ted to the culture broth of Aspergillus furmigatus furmigatus. The isolated phenylglycine showed L-configuration with 80% optical purity. Examination of the hydrolysis of the substrate to phenylglycine with cell free extracts, and the supernatant fraction and the particulate fraction both of which were obtained after ultracentrifugation of the cell free extract at 100,000g, indicated that the nitrile group hydrolyzing enzymes, nitrilase existed not only in cytoplasm, but in microsome fractions.

• YAKHAK HOEJI
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• v.47 no.3
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• pp.130-134
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• 2003

For the development of new synthetic method for unnatural amino acid esters, N-aryl phenylglycine Ο-alkyl esters 4a∼i were synthesized through base-catalyzed hydrolysis of 1,5-diphenylhydantoins 1a∼b and Ο-alkylation in 16∼87％ yield. An efficient and practical route for final 4a∼i was that the starting materials 1a∼b were heated in dil-methanol for 30 minute using sodium hydroxide or potassium hydroxide and evaporated. In addition, reaction mixture were refluxed for 1 h in DMF. All synthetic process from hydantoin to N-aryl phenylglycine Ο-alkyl esters 4a∼i could be carried out in one-pot without isolation of intermediates.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.551-552
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• 2001

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.329-332
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• 2001

It has been known that, in enzymatic synthesis of cephalexin, the conversion yield was reduced by high loading of ampicillin acylase. In order to elucidate this phenomena, pH-controlled synthesis of cephalexin was examined using a purified Acetobacter turbidans acylase. When the pH of the reaction mixture was maintained at $6.20{\pm}0.04$, the reduction of the maximal conversion rate was not observed even with high enzyme loading. The kinetic parameters also suggest that pH drop during the enzymatic synthesis of cephalexin was mainly attributed to the rapid hydrolysis of D-${\alpha}$-phenylglycine methyl ester to D-${\alpha}$-phenylglycine, rather than the disappearance of 7-amino-3-deacetoxycephalosporanic acid for cephalexin synthesis. At higher molar ratio of two substrates, [D-${\alpha}$-phenylglycine methyl ester]/[7-amino-3-deacetoxycephalosporanic acid], the conversion rate was also elevated under pH-controlled enzymatic synthesis, which implies that the main reason for the pH drop is due to the production of D-${\alpha}$-phenylglycine methyl easter, the effect of a water-methanol cosolvent system on the ester, the effect of a water-methanol cosolvent system on the conversion profile was also examined. Even the though the conversion rate was increased in 10% methanol solution, a higher than 16% methanol in the reaction mixture caused an inactivation of enzyme.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.506-511
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• 1997

For the production of benzoylformic acid from DL-phenylglycine, 8 strains of bacteria capable of producing benzoylformic acid were isolated from soil. Among them, the strain YH-001 showed the highest activity for production of benzoylformic acid, and was partially identified as a Bacillus sp. For the production of benzoylformic acid, a reaction mixture and reaction conditions were optimized as follows: the reaction mixture contained 2 g of DL-phenylglycine and 50 g of wet cells in 1 l of 50 mM potassium phosphate buffer (pH 8.0) and the reaction was carried out at 40$circ$C with shaking. After 6 hr incubation, 1.01 g/l of benzoylformic acid was produced which coffesponded to a conversion yield of 50.5%.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.276-282
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• 2003

For the development of new synthetic method for unnatural amino acid esters, N-aryl phenylglycine Ο-alkyl esters 4a∼i were synthesized through esterification, bromination, C-N bond formation from commercially available phenylacetic acids. An efficient and practical reaction condition for esters 2a∼c was that the starting materials 1a∼c were refluxed in absolute methanol for 3 hours with catalytic concentrated hydrosulfuric acid. In addition, bromines 3a∼c were formated for 3h in dichloromethane at rt with N-bromosuccinimide. Bromines 3a∼c were also converted to 4a∼i through substitution of arylamines during refluxing for 24 hours in ethanol with triethylamine. Interestingly, ethyl esters 5a∼c were formed via transesterification reaction when the p-sulfamylanilino group was used as a nucleophile in ethanol solvent.

• Bulletin of the Korean Chemical Society
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• v.4 no.2
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• pp.72-76
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• 1983

Cephaloglycin was synthesized directly from D-${\alpha}$ -phenylglycine methyl ester and 7-aminocephalosporanic acid using whole cell enzyme of Xanthomonas citri (IFO 3835). Some optimal conditions for cephaloglycin synthesis were investigated, and yield improvements for its production by several methods were attempted. Using the whole cell enzyme system, the reaction kinetic model for cephaloglycin synthesis is proposed, and the kinetic constants for D-${\alpha}$ -phenylglycine methyl ester hydrolysis, cephaloglycin synthesis, and cephaloglycin hydrolysis were determined. The $K_m$ values of D-${\alpha}$-phenylglycine methyl ester, 7-aminocephalosporanic acid, and cephaloglycin were 11 mM, 24 mM, and 167 mM, and $K_i$ value of D-${\alpha}$-phenylglycine was 15 mM, respectively. The pattern of product inhibition was found to be competitive one.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1291-1294
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• 2002

Various racemic N-protected ${\alpha}-amino$ acids such as N-t-BOC-(tert-butoxycarbonyl), N-CBZ-(benzyloxycarbonyl) and N-FMOC-(9-fluorenylmethyloxycarbonyl) ${\alpha}-amino$ acids were resolved as their anilide and 3,5-dimethylanilde derivatives on an HPLC chira l stationary phase (CSP) developed by modifying a commercial (S)-leucine CSP. The chromatographic resolution results were compared to those on the commercial (S)-leucine CSP. The resolutions were greater on the modified CSP than those on the commercial CSP with only one exception, the resolution of N-t-BOC-phenylglycine anilide. In addition, the chromatographic resolution behaviors were quite consistent except for the resolution of N-protected phenylglycine derivatives, the (S)-enantiomers being retained longer. Based on the chromatographic resolution behaviors and with the aid of CPK molecular model studies, we proposed a chiral recognition mechanism for the resolution of N-protected ${\alpha}-amino$ acid derivatives. However, for the resolution of N-protected phenylglycine derivatives, a second chiral recognition mechanism, which competes in the opposite sense with the first chiral recognition mechanism, was proposed. The two competing chiral recognition mechanisms were successfully used in the rationalization of the chromatographic behaviors for the resolution of N-protected phenylglycine derivatives.

• Journal of the Korean Chemical Society
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• v.20 no.3
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• pp.229-235
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• 1976

Phenylacetic acid is chlorinated photochemically in carbon disulfide and carbon tetrachloride solvents to obtain ${\alpha}$-chlorophenylacetic acid in $43{\%}$ yield (after separation and purification). The amination of ${\alpha}$-chlorophenylacetic acid yielded the desired dl-phenylglycine in $16\sim27{\%}$ yield depending on the solvent used. Sensitized photophenylation of glycine is also attempted utilizing benzoylperoxide as a phenyl radical source in benzene or acetone solvent.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.525.2-525
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• 1986

Cephalexin synthesizing enzyme (${\alpha}$ amino acid ester hydrolase) was partially purified from the culture broth of Acetobacter turbidans ATCC9325 through ammonium sulfate fractionation, DEAE, CM, and Sephacryl S-200 gel filtration. The enzyme has optimum pH 6.0 and temperature, 40$^{\circ}C$ respectively. From the analysis of reaction mixtures by thin layer chromatographic and high performance liquid chromatographic techniques, it was confirmed this enzyme catalyzed simultaneously the following reactions : 1) Synthesis of cephalexin from D-${\alpha}$-phenylglycine methylester (PGM) and 7-amino 3-deacetoxy-cetoxycephalosporanic acid (7-ADCA) 2) Hydrolysis of cephalexin to form 7-ADCA and phenylglycine (PG) 3) Hydrolysis of PGM to form PG and methanol. Base on the above experimental observations, the reaction model of this enzyme was identical with that of the enzyme from Xanthomonas citri.