Studies on Coumarins of a Chinese Drug “Qian-Hu”, IV.1

Two new and six known coumarins were obtained from the Chinese drug sold in the market under the name of Si-Oian-Hu (Seizenko). The new compounds were proved to be 3'( S)-acetoxy-4'( R)-isovaleryloxy- and 3'( S)-acetoxy-4'( R)-angeloyloxy-3',4'-dihydroxanthyletin, respectively. Mass spectrometry was applied to determine the different locations of ester moieties at the 3' and 4' positions without using alkaline hydrolysis. The present material, Si-Qian-Hu, should be identified with Zi-Hua Qian-Hu (the root of PEUCEDANUM DECURSIVUM), since it contains xanthyletin-type coumarins.