[Isolation and structure elucidation of longshengensin A from Peucedanum longshengense].

Two compounds were isolated from Peucedanum longshengense Shan et Sheh for the first time. Their structures were identified as longshengensin A (I) and mannitol (II) by physico-chemical constants and spectral analyses (UV, IR, MS, NMR and 2D-NMR). I is a new compound with the structure of (-)-3' (s)-acetyloxy-4' (s)-angeloyloxy-3', 4'-dihydroseselin and named longshengensin A. Its absolute configurations were determined by chemical correlation with khellactone.