Abstract
A highly unsaturated new amide, (2E,4Z,8Z,10Z)-N-isobutyl-2,4,8,10-dodecatetraenamide (1), was isolated in very small quantities from the whole plant of Asarum forbesii Maxim. together with four known compounds, (2E,4E,8Z,10E)-N-isobutyl-2,4,8,10-dodecatetraenamide (2), (−)-sesamin (3), (−)-asarinin (4) andE)-asarone5). The Z/E isomers, 1 and 2, were separated successfully by developed silver-ion medium-pressure liquid chromatography (SIMPLC). Compound 2 and the two diastereoisomers, 3 and 4, were isolated from this plant for the first time. The characterization of these compounds was achieved by various spectroscopic methods.
Acknowledgements
We acknowledge the support of CMST (Chinese Ministry of Science and Technology) which made the work possible (the investigation presented here is a part of the program numbered G19990554 of CMST). We are also grateful to Professor C. Chen, Liaoning Normal University, for his help in identifying the plant material.