Dimeric sesquiterpene and thiophenes from the roots of Echinops latifolius.

Phytochemical investigation of the roots of Echinops latifolius led to the isolation of a new carbon skeleton dimeric sesquiterpene (1) and a new thiophene (2), along with six known compounds (3-8). Their structures and relative stereochemistry were elucidated by spectroscopic and spectrometric methods (1H and 13C NMR, COSY, HSQC, HMBC, ROESY, and MS). All isolates were evaluated for their inhibition of LPS-induced NO production in RAW 264.7 cells. Compounds 4 and 5 exhibited the most potent inhibitory effects on NO production. Copyright Â