Separation of acid diterpenes of Copaifera cearensis Huber ex Ducke by flash chromatography using potassium hydroxide impregnated silica gel

Various acid diterpenes of Copaifera cearensis Huber ex Ducke were isolated from the crude extract by flash Silica Gel/Potassium Hydroxide Chromatogra phy. The main components were identified by GC-MS analyses. Further fractio nation by reversed phase (RP) semi-preparative HPLC allowed isolation and i dentification of minor components and provided additional spectral data of those compounds. It was possible to detect the presence of eleven acid dite rpenes in addition to a sesquiterpene acid. In addition to potassium hydrox ide deposition on the silica surface, the presence of Si-OK residues, resul ting from a cation exchange process, was established.