Diterpenoid alkaloids from Delphinium trichophorum

Three new hetisine type C20-diterpenoid alkaloids, named as trichophorines A-C (1-3), were isolated from Delphinium trichophorum, together with nine known alkaloids (4-12). Their structures were elucidated on the basis of spectroscopic data (1D, 2D NMR, single-crystal X-ray, and HR-ESI-MS). All compounds were evaluated for the inhibitory activities against LPS induced NO production in RAW 264.7 macrophage cells, and none of them showed considerable inhibitory activity.