Identification of new diterpenoids from Euphorbia calyptrata cell cultures

Four new diterpenoids, helioscopinolides F (2), H (4), I(5), and L (6), were isolated from three different cultured cell lines of Euphorbia calyptrata var. involucrata. Helioscopinolide B (1) and jolkinolide E (3), previously found in Euphorbia helioscopia and Euphorbia jolkini, respectively, were also isolated from the same cultures. Structures were identified by spectroscopic methods.