title: Trigohowilols A-G, degraded diterpenoids from the stems of Trigonostemon howii.
abstract: Two new degraded diterpenoids, trigohowilols A (1) and B (2), four new heterodimers, trigohowilols C-F (3-6), one new homodimer, trigohowilol G (7), and three known degraded diterpenoids (8-10) were isolated from the methanol extract of the stems of Trigonostemon howii. Compounds 1-7 were evaluated for their cytotoxic activity against five human tumor cell lines by an MTT assay, and trigohowilols E (5) and F (6) exhibited inhibitory activity with IC50 values ranging from 2.33 to 12.57 μM. Moreover, compounds 1-6 showed weak antimicrobial activities (MIC values: 6.25-25 μg/mL) against Staphylococcus aureus, Pseudomonas aeruginosa, MRSA 92(#), and MRSA 98(#) using a 2-fold dilution method.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, Yunnan, People's Republic of China.
authors.forename: Gui-Hua
authors.initials: GH
authors.lastname: Tang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chun-Mao
authors.initials: CM
authors.lastname: Yuan
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Gu
authors.forename: Ying-Tong
authors.initials: YT
authors.lastname: Di
authors.forename: Yue-Hu
authors.initials: YH
authors.lastname: Wang
authors.forename: Guo-Ying
authors.initials: GY
authors.lastname: Zuo
authors.forename: Shi-Fei
authors.initials: SF
authors.lastname: Li
authors.forename: Shun-Lin
authors.initials: SL
authors.lastname: Li
authors.forename: Hong-Ping
authors.initials: HP
authors.lastname: He
authors.forename: Xiao-Jiang
authors.initials: XJ
authors.lastname: Hao
mesh_terms: D000900:Anti-Bacterial Agents / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004224:Diterpenes / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D019665:Euphorbiaceae / Q000737:chemistry*; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018547:Plant Stems / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013203:Staphylococcal Infections / Q000188:drug therapy; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000972:Antineoplastic Agents, Phytogenic; D004224:Diterpenes; D004365:Drugs, Chinese Herbal; C587521:trigohowilol E; C587520:trigohowilol F