Abstract:A new macrocyclic lactam which was named clausenlactam (1), together with known components zapoterin (2), myricetin-3-O-rhamnoside (3), ferulic acid (4), 7-hydroxycoumarin (5) and tnethylamine hydroiodide was isolated from Clausena exca.ata Burm. f. Its chemical structure was elucidated as 1, r-docosanedilactam by means of spectroscopic methods.