Cumingianols G and H, new 14,18-cycloapoeuphane triterpenoids from the Taiwan <i>Dysoxylum cumingianum</i> C. DC.

Two new 14,18-cycloapoeuphane triterpenoids, cumingianols G (1) and H (2), along with 12 known compounds, cumingianol C (3), cumingianol A (4), cumingianol D (5), 3,3-ethylenedioxy-5α-cycloart-24-en-23-one (6), 24,25(<i>R</i>,<i>S</i>)-24,25-epoxy-20(<i>S</i>)-hydroxydammar-3-one (7), (3β,7α)-stigmast-5-ene-3,7-diol (8), 7α-hydroxystigmasterol (9), 7β-hydroxysitosterol (10), 7β-hydroxystigmasterol (11), ethylcholest-5-en-3-hydroxy-7-one (12), coniferaldehyde (13) and 4-hydroxy-3,5-dimethoxy-benzaldehyde (14), have been isolated from <i>Dysoxylum cumingianum</i> collected in Taiwan. The structures of these metabolites were determined through mass spectrometry and 1D and 2D NMR analyses, combined with comparisons to reference data. The cytotoxic effects of these isolates were evaluated against human oral squamous cell carcinoma (SCC2095), human breast adenocarcinoma (MCF-7), and human gastric adenocarcinoma (SCM-1). Among them, compound 4 exhibited significant cytotoxicity against the SCC2095 and MCF-7 cell lines, with IC₅₀ values of 6.3 μM and 6.1 μM, respectively.