The fourth fraction (0.15 g) was precipitated in MeOH to give compound 12 (6.2 mg) and the filtrate was further purified by a preparative HPLC using a linear gradient system 10–50% aqueous CH3CN for 20 min to furnish compounds 12 (3.5 mg), 4 (16.2 mg), and 3 (28.8 mg), respectively.