A process is provided for the preparation of pure cyclosporin which is purified chromatographically from a mixture of different cyclosporin forms and other substances prepared by fermentation. The process comprises feeding a mixture containing a desired form of cyclosporin with an eluent
A method is provided for supplying the desired optical isomer of a derivative of epoxypropionic acid from a racemix mixture. A representative derivative of epoxypropionic acid is an ester of (p-methoxyphenyl)epoxypropionic acid. The racemic mixture initially is dissolved in carbon di