A new γ‐lactone found in butter

Abstract
A characteristic component of butter flavour is 2,3‐dimethyl‐2,4‐nonadien‐4‐olide, the enol lactone of 2,3‐dimethyl‐4‐oxo‐2‐nonenoic acid. Homologues have not been found. The substance which has a strong odour reminiscent of celery and occurs in an amount of about 0.5 mg/kg butter, was called “bovolide”.The elucidation of its structure and its synthesis are described. Also several related compounds have been synthesized.