Preparative isolation and purification of two phenylbutenoids from the rhizomes of Zingiber Cassumunar by upright counter-current chromatography

Two phenylbutenoids, ( E )-4-(3′,4′-dimethoxyphenyl)but-3-enyl acetate and ( E )-4-(3′,4′-dimethoxyphenyl)but-1,3-diene, were separated from the rhizomes of Zingiber Cassumunar using a preparative upright counter-current chromatography (CCC). With a two-phase solvent system composed of light petroleum (b.p. 60–90 °C)–ethanol–diethyl ether–water (5:4:2:1, v/v), 150 mg of ( E )-4-(3′,4′-dimethoxyphenyl)but-3-enyl acetate and 175 mg of ( E )-4-(3′,′-dimethoxyphenyl)but-1,3-diene with the purity of 98.7 and 95.1%, respectively, were obtained from 600 mg of the crude sample of Z. Cassumunar in a single-step separation. Structures of these two compounds were identified by ESI-MS, 1 H NMR and 13 C NMR.