title: A new thiophene and two new monoterpenoids from Xanthium sibiricum.
abstract: Three new compounds (1-3), together with six known compounds (4-9), were isolated from the fruits of Xanthium sibiricum. The structures and the absolute configurations of sibiricumthionol (1), (+)-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [(+)-2], ( - )-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [( - )-2], (2E,4E,1'S, 2'R, 4'S, 6'R)-dihydrophaseic acid (3), (+)-xanthienopyran [(+)-4] and ( - )-xanthienopyran [( - )-4] were established by extensive spectroscopic analyses, X-ray crystallographic analysis, ECCD analysis and ECD calculations. Caffeic acid (7) and caffeic acid ethyl ester (8) weekly inhibited α-glucosidase enzymatic activity by 44.5% and 40.2%, respectively, at 40 μM. Protocatechuic acid (9) selectively exhibited cytotoxicity against HepG2 cell lines, with an IC50 value of 2.92 μM.
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Yu-Sheng
authors.initials: YS
authors.lastname: Shi
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Yun-Bao
authors.initials: YB
authors.lastname: Liu
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Shuang-Gang
authors.initials: SG
authors.lastname: Ma
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Jing
authors.initials: J
authors.lastname: Qu
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Liu
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Zhu-Fang
authors.initials: ZF
authors.lastname: Shen
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Xiao-Guang
authors.initials: XG
authors.lastname: Chen
authors.affiliation: a State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050 , China.
authors.forename: Shi-Shan
authors.initials: SS
authors.lastname: Yu
mesh_terms: D002109:Caffeic Acids / Q000737:chemistry / Q000494:pharmacology; D018360:Crystallography, X-Ray; D005638:Fruit / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D020128:Inhibitory Concentration 50; D008968:Molecular Conformation; D015394:Molecular Structure; D039821:Monoterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism; D013876:Thiophenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D031210:Xanthium / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000187:drug effects
chemical_list: D002109:Caffeic Acids; D039821:Monoterpenes; D013876:Thiophenes; C032773:ethyl caffeate; D000520:alpha-Glucosidases; C040048:caffeic acid
keywords: Xanthium sibiricum; monoterpenoid; sesquiterpene; thiophene