Isolation and structure determination of new spiro‐bicyclic triterpenoids from <i>Iris pseudacorus</i>

Abstract

Abstract Four novel types of iridals (compounds 8, 9, 15 and 16 ) have been isolated from lipid extracts of roots and rhizomes of I. pseudacorus and their structures (except the stereochemistry of 15 at C‐13 and C‐26 and of 16 at C‐13) elucidated by oxidative degradation combined with spectroscopic methods. They are up to now unknown triterpenoids with unusual spiro‐bicyclic structures. The possible biogenesis of these compounds is descussed.