Five rare C32 sesquiterpene lactone dimers with anti-inflammation activity from Vladimiria souliei

Five rare sesquiterpene lactone dimers, vlasouliolides E-I, were isolated from Vladimiria souliei. Their chemical structures were elucidated by spectroscopic analysis. Furthermore, 2 and 4 were unambiguously confirmed by Cu-Kα X-ray crystallographic analysis.248