New highly irritant euphorbia factors from latex of Euphorbia tirucalli L

Abstract

From the latex of Euphorbia tirucalli L. growing in Madagascar, 5 new euphorbia factors were isolated. They were characterized as 13-O-acetyl-12-O-acylphorbol- and 12-O-acetyl-13-O-acylphorbol derivatives carrying homologous conjugated unsaturated fatty acids as acyl groups. Furthermore, 2 mixtures of homologous 3-O-acylingenol derivatives are obtained carrying the same type of unsaturated fatty acids. Due to their highly unsaturated acyl groups all Euphorbia factors or factor groups isolated are highly sensitive to autoxidation.