title: Two new thiophenes from Echinops latifolius and their phototoxic activities.
abstract: 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.
authors.affiliation: Research Department of Natural Medicine, Shenyang Pharmaceutical University, Shenyang, P.R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Xian
authors.initials: X
authors.lastname: Li
authors.forename: Lin-Hao
authors.initials: LH
authors.lastname: Li
authors.forename: Da-Li
authors.initials: DL
authors.lastname: Meng
authors.forename: Zhan-Lin
authors.initials: ZL
authors.lastname: Li
authors.forename: Ning
authors.initials: N
authors.lastname: Li
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D019659:Asteraceae; D045744:Cell Line, Tumor / Q000187:drug effects; D006801:Humans; D020128:Inhibitory Concentration 50; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D013876:Thiophenes / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D013876:Thiophenes