A New Diterpene Lactone, Rosmadial, from Rosemary (Rosrnarinus officinalis L.)

Abstract

A new type of phenolic diterpene lactone, named rosmadial (1), was isolated from the leaves of rosemary (Rosmarinus officinalis L.), one of the herb spices belonging to the Family Labiatae. The structure has been determined to be 12-hydroxy-6, 7-seco-11, 10-epoxymethano-20-oxo-abieta- 8, 11, 13-triene-6, 7-dial by chemical and spectroscopic methods. The structure and stereochemistry were confirmed by synthesis from carnosol (5).