Macrocyclic Lathyrane Type Diterpene Esters (Jolkinols) from Callus Cultures and Roots ofEuphorbia lathyris

In an acetone extract of callus cultures of Euphorbia lathyris the occurrence of diterpene esters of the lathyrane and ingenane type was investigated. From the extract of the cultures which did not show irritant activity on the mouse ear the non-irritant macrocyclic diterpene esters jolkinol A and A′ were isolated. Comparative studies of irritant extracts of roots and of aerial parts resulted in the isolation of jolkinol B from roots. The irritant activities of these plant parts of E. lathyris most probably indicate the presence of ingenane type diterpene esters previously isolated from seeds and latex.