Polysubstituted Cyclopentene Benzamides and Dianthramide Alkaloids from Delphinium anthriscifolium Hance.

Thirteen new benzamide alkaloids, delphiniumines A-M ( 1 - 13 ), together with one known analogue ( 14 ), were isolated from Delphinium anthriscifolium Hance. All of the structures were determined by spectroscopic and spectrometric analyses. Absolute configuration for 1 was established using experimental and calculated ECD data, as well as by X-ray crystallography analysis. Compound 1 possesses a previously undescribed polysubstituted cyclopentene carbon framework. Compound 2 was isolated as an artifact from 1 during the extraction process. Compound 7 is glycosylated with a β-D-glucose unit. Compound 13 bears a chlorine substituent. At a concentration of 10 μM, compounds 6 , 8 , and 10 - 12 suppressed LPS-induced NO production in RAW264.7 cells with inhibition rates ranging from 40.3% to 78.8%.