Helenalinmethacrylate, a new Pseudoguaianolide from the Flowers of Arnica montana L. and the sensitizing Capacity of their Sesquiterpene Lactones

Abstract

Helenalinmethacrylate, a new ester from helenalin, and helenalinacetate were isolated from the flowers of Arnica montana. L. (Asteraceae). The structure of helenalinmethacrylate was established. Based on sensitizing experiments in guinea pigs helenalin, isolated from the flowers of A. longifolia, and helenalinacetate must be considered as contact allergens. Helenalinacetate and helenalinmethacrylate could be considered as sensitizers for the often observed allergic contact dermatitis caused by the flowers of A. montana and the „Tinctura Arnicae”.

Key Word Index

Arnica montana L - Asteraceae - New Pseudoguaianolide: Helenalinmethacrylate - Contact Allergens - Helenalinacetate - Helenalin