| 摘要 |
<p>The object of the present invention is a process for producing optically pure S-timolol or its derivatives wherein racemic R,S-timolol, or its racemic derivative, at elevated pressure and dissolved in carbon dioxide is periodically fed to a chromatographic column, through which is led a continuous flow of eluent which mainly contains carbon dioxide. The chromatographic column is filled with a chiral packing material, which may be silica gel particles covered with cellulose esters or cellulose carbamates. The eluent flow, which leaves the chromatographic column, is periodically divided into fractions so that the S-timolol, or its derivative, is collected at the desired purity in one fraction. The pressure of the product flow is reduced in such a way that the S-timolol, or its derivative, is precipitated from the eluent flow and is recovered.</p> |
