Trigohowilols A–G, Degraded Diterpenoids from the Stems of Trigonostemon howii

• Published in: Journal of natural products (Washington, D.C.) D.C.), 2012-11, Vol.75 (11), p.1962-1966
• Main Authors: Tang, Gui-Hua, Zhang, Yu, Yuan, Chun-Mao, Li, Yan, Gu, Yu-Cheng, Di, Ying-Tong, Wang, Yue-Hu, Zuo, Guo-Ying, Li, Shi-Fei, Li, Shun-Lin, He, Hong-Ping, Hao, Xiao-Jiang
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - isolation & purification; Anti-Bacterial Agents - metabolism; Anti-Bacterial Agents - pharmacology; Antineoplastic Agents, Phytogenic - chemistry; Antineoplastic Agents, Phytogenic - isolation & purification; Antineoplastic Agents, Phytogenic - pharmacology; Diterpenes - isolation & purification; Diterpenes - metabolism; Diterpenes - pharmacology; Drug Screening Assays, Antitumor; Drugs, Chinese Herbal - chemistry; Drugs, Chinese Herbal - isolation & purification; Drugs, Chinese Herbal - pharmacology; Euphorbiaceae - chemistry; Humans; Methicillin-Resistant Staphylococcus aureus - drug effects; Microbial Sensitivity Tests; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Plant Stems - chemistry; Pseudomonas aeruginosa - drug effects; Staphylococcal Infections - drug therapy; Staphylococcus aureus - drug effects
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np3006315

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.