A New Bithiophene from the Root of Echinops grijsii

Abstract

A new bithiophene, 5-(4-hydroxy-3-methoxy-1-butyny)-2,2′-bithiophene (1), and sixteen known thiophenes: 2-(3,4-dihydroxybut-1-ynyl)-5-(penta-1,3-diynyl)thiophene (2), α-terthienyl (3), 5-(3,4-dihydroxybut-1-ynyl)-2,2′-bithiophene (4), 5-acetyl-2,2′-bithiophene (5), 5-formyl-2,2′-bithiophene (6), methyl 2,2′-bithiophene-5-carboxylate (7), 5-(but-3-en-1-ynyl)-2,2′-bithiophene (8), 5-(4-isovaleroyloxybut-1-ynyl)-2,2′-bithiophene (9), cardopatine (10), isocardopatine (11), 5-(3-hydroxy-4-isovaleroyloxybut-1-ynyl)-2,2′-bithiophene (12), 5-(3-hydroxymethyl-3-isovaleroyloxyprop-1-ynyl)-2,2′-bithiophene (13), 5-(4-hydroxy-1-butynyl)-2,2′-bithiophene (14), 5-(4-acetoxy-1-butynl)-2,2′-bithiophene (15), 2,2′-bithiophene-5-carboxylic acid (16) and 2-(4-hydroxybut-1-ynyl)-5-(penta-1,3-diynyl)thiophene (17) were isolated from the roots of Echinops grijisii Hance. Among them, compounds 6, 7 and 16 were isolated from a natural source for the first time. Compounds 2, 4 and 14 exhibited significant anti-inflammatory activity against nitrite of LPS-stimulated production in the RAW 264.7 cell line.