| 摘要 |
<p>PURPOSE:To obtain the titled compound useful as an intermediate for pharmaceuticals such as carnitine or GABOB, in high efficiency, by reducing a gamma-haloacetoacetic acid ester with an enzyme extracted from bakers' yeast and having a specific molecular weight. CONSTITUTION:The enzyme used in the present process has the following properties: mol.wt., 55,000-68,000; optimum pH, 5.5; stable pH range, 6.5-8.0; optimum temperature, 30 deg.C; isoelectric point, pH 5.1; inhibition, inhibited by Cu, Hg, etc.; etc. A proper amount of the enzyme is added to water or a buffer solution of pH 4-8 containing 0.1-10% of a gamma-haloacetoacetic acid ester and is made to react at 15-40 deg.C for 1min-50hr under agitation. The objective gamma-halo-beta(R)- hydroxybutyric acid ester is produced from the obtained reaction product e.g. by solvent extraction.</p> |
