A new diterpene from the stems of Trigonostemon heterophyllus

AIM:To investigate the chemical constituents in the stems of Trigonostemon heterophyllus.METHOD:The chemical constituents were isolated by column chromatography on silica gel,Rp-18,and Sephadex LH-20,and their structures were elucidated on the basis of spectroscopic analysis.RESULTS:Three compounds were isolated and identified as a new diterpene,trigonoheterene B(1),together with two known compounds,trigonostemone(2) and trigonochinene B(3).CONCLUSION:Compound 1 is new.Compounds 2 and 3 showed antibacterial activities.