Ergostane steroids from the ethanol extract of Dysoxylum mollissimum.

Three new ergostane steroids, 7α-acetoxyl-ergosta-5,24(28)-diene-3β,4β,20S-triol (1), 7α-acetoxyl-ergosta-5,24(28)-diene-3β,4β-diol (2), and 7α-acetoxyl-ergosta-5,24(28)-3β-ol (3) were isolated from the ethanol extract of stem bark of Dysoxylum mollissimum BI. Structural elucidation of all the compounds was performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. All the isolated steroids were in vitro evaluated for their anti-inflammatory activity against COX-1 and COX-2. As a result, steroids 1-3 exhibited modest selective inhibition for COX-1 (>60%).