Removal of the solvent under reduced pressure provided CH2Cl2 crude extract (118.5 g) that was further separated by column chromatography over silica gel (Merck Art 7730) (1.5 kg) and eluted with a gradient of hexane–EtOAc (100% hexane, 80%, 60%,40%, 20% and 100% EtOAc each 5 L, respectively) to give five fractions (A–E).