Anti-inflammatory triterpenes from the apical bud of Gardenia sootepensis

Bioassay-guided fractionation of the dichloromethane extract from the apical bud of Gardenia sootepenesis Hutch. (Rubiaceae) led to the isolation of four new cycloartane triterpenes, sootepins F-I (1-4), along with four known derivatives (5-8). The structures of the new compounds were determined by 1D and 2D NMR experiments and by comparison of the physicochemical data with published values. The isolates were evaluated for cancer chemopreventive potential based on their ability to inhibit nitric oxide (NO) production and tumor necrosis factor-alpha (TNF-α)-induced nuclear factor kappa (NF-κB) activity. Compounds 6-8 inhibited TNF-α-induced NF-κB activity with half maximal inhibitory concentration (IC₅₀) values of 8.3, 5.6, and 6.0μM, respectively; compounds 7 and 8 showed significant NO-inhibitory activity with IC₅₀ values of 3.2 and 2.0μM, respectively.