Anti-inflammatory Meroterpenoids from Baeckea frutescens
- J Nat Prod. 2017 Aug 25;80(8):2204-2214. doi: 10.1021/acs.jnatprod.7b00042.
- 1. State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, and ‡Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University , Nanjing 210009, People's Republic of China.
Frutescones H-R (1-11), new sesqui- or monoterpene-based meroterpenoids, were isolated from the aerial parts of Baeckea frutescens. Their structures and absolute configurations were established by means of spectroscopic analyses (HRESIMS, 1D and 2D NMR, and ECD), as well as single-crystal X-ray crystallography of 1, (-)-7, and 9. The anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on NO production in LPS-stimulated RAW 264.7 macrophages, and the structure-activity relationships of 1-11 are also discussed. Compound 8 exhibited anti-inflammatory activity with an IC50 value of 0.36 μM, which might be related to the regulation of the NF-κB signaling pathway via the suppression of p65 nuclear translocation and the consequent decrease of IL-6 and TNF-α.