title: Chemical Constituents of the Roots of Euphorbia micractina.
abstract: Nine minor new tirucallane (1-7) and euphane (8 and 9) triterpenoids including five hydroperoxides, together with 18 known compounds, have been isolated from an ethanolic extract of the roots of Euphorbia micractina. Their structures including absolute configurations were elucidated by spectroscopic and chemical analysis. In the in vitro assays, betulin (10) showed a selective cytotoxic activity against A2780 ovarian cells with an IC(50) value of 6.1 microM and inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) with an IC(50) value of 15.3 microM. Jolkinol B (11) showed a potent activity against HIV-1 replication with an IC(50) value of 12.6 muM. However, compounds 1-9 and the other known compounds were inactive in the three assays used.
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College (Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education), Beijing, People's Republic of China.
authors.forename: Wendong
authors.initials: W
authors.lastname: Xu
authors.forename: Chenggen
authors.initials: C
authors.lastname: Zhu
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.forename: Xiaona
authors.initials: X
authors.lastname: Fan
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Chen
authors.forename: Sen
authors.initials: S
authors.lastname: Yang
authors.forename: Ying
authors.initials: Y
authors.lastname: Guo
authors.forename: Fei
authors.initials: F
authors.lastname: Ye
authors.forename: Jiangong
authors.initials: J
authors.lastname: Shi
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D028481:Euphorbia / Q000737:chemistry*; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D015394:Molecular Structure; D018517:Plant Roots / Q000737:chemistry; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000037:antagonists & inhibitors; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D014315:Triterpenes; C514393:tirucallane; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1