Studies On The Chemical Constituents And Biological Activities Of The Roots Of Echinops Latifolius Tausch

Echinops latifolius Tausch (Compositae) is widespread in north China. The roots of this plant has been recorded in Chinese Pharmacopoeia (1995 Edition) as Radix Echinopsis. Radix Echinopsis is a traditional Chinese medicine used as dear heat, expel miasma and stimulate milk secretion.From the 95% ethanol extract of the roots of Echinops latifolius Tausch, 39 compounds were isolated by means of solvent partition, repeated column chromatography on silica gel and Sephadex LH-20, P-TLC. On the basis of spectroscopic analysis (NMR, MS) and physical-chemical characters, their structures were identified as Thiophenes:α-terthienyl (1), 5-(but-3-en-1-ynyl)-2,2'-bithiophene (2), cardopatine (3), isocardopatine (4), 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5), 5-(3-acetoxy-4-isovaleroyloxybut-1-ynyl)- 2,2'- bithiophene (6), 5-(3-hydroxy-4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (7), 5-(3- isovaleroyloxy-4-hydroxybut-1-ynyl)-2,2'-bithiophene (8), echinoetherthiophene (9), 5-(4-hydroxybut-1-ynyl)-2,2'-bithiophene (10), 5-(3,4-dihydroxybut-1- ynyl)-2,2'-bithiophene (11), 5-(4-hydroxybut-1-one)-2,2'-bithiophene (12), 5-acetyl-2,2'-bithiophene (13), 5-carbamoyl-2,2'-bithiophene (14), 2-(pent-1,3-diynyl)-5-(4-hydroxybut-1-ynyl)-thiophene (15), 2-(pent-1, 3-diynyl)-5-(3,4-dihydroxybut-1-ynyl)-thiophene (16); Triterpenes: taraxerol acetate (17), friedelin (18), ursolic acid (19);Sterols: ergosterol peroxide (20), 9(11)dehydro-ergosterol peroxide (21), stigmast-5,22-dien-3β-ol-7-one (22), stigmast-4-ene-3β, 6β-diol (23),α-spinasterol(24),β-sitosterol (25), daucosterol (26); Aromatic series: tyrosol (27),4-hydroxy-benzoic acid (28), 4-hydroxyphenylacetic acid (29), ] 4-hydroxyphenylacetic acid ethyl ester (30), protocatechuic acid (31), protocatechuic acid ethyl ester (32), vanillin (33), vanillie acid (34); Organic acids and ether: succinic acid (35), n-tetracosanoic acid (36), palmitic acid (37), glyceryl monostearate (38); saeeharide: sucrose (39).Among them, compounds 8, 9, 12 are new compounds; compound 14 is a new natural product; compounds 4, 5, 6, 7, 10, 13, 15, 18, 20, 21, 22, 23, 24, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38 were firstly isolated from this plant.The extracts were examined for their cell cycle inhibitory and apoptosis inducing activities using K562 cells. The anti-tumor parts were found in the petroleum ester extract and the chloroform extract.By MTT and SRB methods, the in vitro cytotoxic activities of the thiophenes isolated were assayed. All the compounds showed significant phototoxic activities against tumor cell lines, dependent on the long wavelength ultraviolet (UVA).On the basis of references, a review was given on the structural categories, distribution, biosynthetic pathway, bioactivities and the studies on the structural elucidation of thiophenes, which is a characteristic composition in Compositae.