Anti-inflammatory lanostane triterpenoids with rearranged spirobi[indene] scaffold and their biogenetically related analogues from Euphorbia maculata

Phytochemical investigations on the ethanol extract of the whole plant of Euphorbia maculata Linn. Resulted in the identification of 16 lanostane-related triterpenoids, including 11 undescribed ones, namely spiromaculatols A-C (1-3) and euphomaculatoids A-H (4-11). The structural determinations of the previously undescribed ones (1-11) were elucidated based on the interpretation of comprehensive spectroscopic data, quantum chemical calculation, as well as X-ray crystallographic experiments. Spiromaculatols A-C (1-3) possess a rare spirobi [indane] skeleton, which was biosynthetically derived from the 7 (8 -> 9)-abeo bond migration of lanostane precursors. The biological activity of compounds 1-3, 5, 7, and 12-13 displayed inhibitory effect on the release of NO in an LPS-activated RAW264.7 cells model. Molecular mechanism study indicated that the most potent spiromaculatol C (3) can reduce the nuclear translocation of NF-kappa B p65 and decrease the transcriptional ex-pressions of its downstream pro-inflammatory mediators.

Automated summary

Phytochemical investigation of Euphorbia maculata Linn. yielded 16 lanostane-related triterpenoids, including 11 previously undescribed compounds. The structures of these compounds were determined through spectroscopic data interpretation, quantum chemical calculation, and X-ray crystallography. The isolated compounds showed inhibitory effects on NO release in LPS-activated RAW264.7 cells, with spiromaculatol C (3) exhibiting the most potent activity by reducing NF-kappa B p65 nuclear translocation.