Wang Yi, Li Xian, Li Lin-Hao, Meng Da-Li, Li Zhan-Lin, Li Ning
Research Department of Natural Medicine, Shenyang Pharmaceutical University, Shenyang, P.R. China.
Planta Med. 2007 Jun;73(7):696-8. doi: 10.1055/s-2007-981541. Epub 2007 Jun 13.
Two new thiophenes, 5-{4-[4-(5-pent-1,3-diynylthiophen-2-yl)-but-3-ynyloxy]-but-1-ynyl}-2,2'-bithiophene (1) and 5-(4-hydroxybut-1-one)-2,2'-bithiophene (2), together with two known thiophenes 5-(4-hydroxybut-1-ynyl)-2,2'-bithiophene (3) and 5-(3,4-dihydroxybut-1-ynyl)-2,2'-bithiophene (4), were isolated from the roots of Echinops latifolius Tausch. Their structures were elucidated based on the detailed NMR spectroscopic analysis and comparison with literature values. Compounds 1 and 2 showed significant inhibition activities against human cancer cell lines A375-S2 and HeLa with IC(50) values from 3.1 to 13.5 micromol/L, depending on their exposure to long wavelength ultraviolet light.
