Two new sesquiterpenes, 8α-(4-hydroxymethacryloyl)-14-acetoxy-salonitenolide (1) and 8α-(2-hydroxymethyl 2-butenoyl)-14-acetoxy-salonitenolide (2), together with five known sesquiterpenes were isolated from the leaves of Vernonia nigritiana Oliv. & Hiern. Their structural characterization was obtained on the basis of extensive NMR spectroscopic and mass spectrometric studies.
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