Four new lycoctonine-type C₁₉-diterpenoid alkaloids from the whole plants of Delphinium kamaonense

Four new lycoctonine-type C₁₉-diterpenoid alkaloids kamaonensines H-K (1-4) have been isolated from the whole plants of Delphinium kamaonense, together with 12 known compounds (5-16). Interestingly, kamaonensines 1-3 contained a rare nitrone (immine N-oxide) moiety, respectively. Their structures were established by spectroscopic analyses. The active evaluation of compounds (1-16) by LPS induced RAW 264.7 macrophages showed that compounds 4 and 8 displayed strong anti-inflammatory activities. While compounds 11 and 12 also showed strong cytotoxicities by the RAW 264.7 cell viability assay.