From the irritant acetone extract of latex of Euphorbia characias six macrocyclic diterpene esters of the following lathyrane type were obtained. The compounds isolated were shown by physico-chemical methods to be five new diesters of the parent alcohol jolkinol-5β,6β-oxide, and one triester of the new parent alcohol 2α-hydroxyjolkinol-5β,6β-oxide. All compounds were practically inactive as irritants.