Chemical and toxicological studies on bracken fern, Pteridium aquilinum var. latiusculum. II. Structures of pterosins, sesquiterpenes having 1-indanone skeleton.

Abstract
The structures of 24 sesquiterpenes isolated from the young fronds of P. aquilinum var. latiusculum were disclosed by chemical and physical methods. The stereostructures were established by degradation and correlation reactions and physical data.