1977 年 97 巻 3 号 p. 237-243
From the ether extract of Cnidium officinale MAKINO (Umbelliferae ; Japanese name "Senkyu"), six phthalides were isolated by column and preparative thin-layer chromatography. One of them was a new phthalide and named senkyunolide. The structure of senkyunolide was determined by correlation with the known butylphthalide as (3S)-3-butyl-4, 5-dihydrophthalide (VI). The mass spectroscopy was found to be the most satisfactory method for structural analysis of phthalides and showed a definate systematic fragmentations starting from the cleavages at the allylic position.