Search for: [Abstract = "ges including\: the easy separation of the latter from the reaction products, the elevation of enzyme concentrations per unit volume, and even the enhancement of enzyme stability and activity. In the present work, we report the use of two D\-hydantoinases\: D\-Hydantoinase, recombinant, immobilized from E. coli \(rD\-Hyd\) and D\-hydantoinase from Vigna angularis \(V.a.D\-Hyd\) for the synthesis of N\-carbamoyl derivatives of several ring\-monosubstituted and ring\-disubstituted D\-phenylalanine analogs, which are next easily converted to the corresponding D\-amino acids. The required 21 racemic \(R,S\) phenyl ring\-substituted 5\-benzylhydantoins were synthesized using at first Knoevenagel’s condensation and then either the catalytic hydrogenation of non\-saturated bond in 5 position of the hydantoin ring in the presence of Pd\/C catalyst or by reduction of appropriate 5\-arylidenehydantoin with 57 % hydroiodic acid in the presence of red phosphorus. To study the activity of D\-hydantoinase towards phenyl ring\-substituted 5 benzylhydantoins the calibration curves for each substrate were estimated by capillary electrophoresis. Obtained regression equations were used to calculate the concentrations of substrates remaining at the time in the reaction mixtures. The efficiencies of the enzymes were expressed in terms of k \(reaction rate constant\) and t0,5 \(substrate half\-life\). Enzymatic activities of b"]

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