Untersuchung der allergenen Prinzipien aus Kolophonium: Autoxidation, Synthese und Sensibilisierung
Investigation of the Allergenic Principles from Colophony: Autoxidation, Synthesis, and Sensitization 
 
 
 
The autoxidation of abietic acid (1a), levopimaric acid (2a), and dehydroabietic acid (3a) was studied and the compounds 3a as well as (after esterification) 8b, 9b, 10b, 11b (from 1a); 6b (from 2a); and 4b, 5b (from 3a) were isolated for the first time. Some derivatives (6a, 6b, 13b/14b, and 7b) were semisynthezised. The isolated autoxidation products, the synthetic compounds and some polar fractions of natural colophony were tested for their sensitizing capacity. Compounds 4a, 10b, 16, and 18 as well as the combined polar fraction A–D of colophony show enhanced sensitizing capacity. Methylation of the acids to the ester significantly reduces their activity.