Diterpenoid alkaloids and flavonoids from Delphinium trichophorum

Five hetisane-type C-20-diterpenoid alkaloids, trichodelphinines A-E, one delnudine-type C-20-diterpenoid alkaloid, trichodelphinine F and three known flavonoids, quercetin, quercetin 3-O-beta-D-glucopyranoside, and quercetin 3-O-beta-D-glucopyranoside-7-O-alpha-L-arabinopyranoside, were isolated from whole plants of Delphinium trichophorum Franch. Their structures were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, H-1-H-1 COSY, NOESY and X-ray crystallographic analysis, and from chemical evidence. The cytotoxic activities of the diterpenoid alkaloids were evaluated using the MTT method, and the IC50 values of their cytotoxicity against A549 cancer cells ranged from 12.03 to 52.79 mu M. (C) 2013 Elsevier Ltd. All rights reserved.