Isolation of Triterpenoid Glycosides (Saikosaponins) fromBupleurum kunmingenseand Their Chemical Stmctures

Five new triterpenoid glycosides named S3, S4, S8, S9 and S10 were isolated from the root of Bupleurum kunmingense, and their structures were elucidated by NMRspectral analysis as 16e/?/-chikusaikoside I, 3^-O-acetylsaikosaponin-a, 4^-0-acetylsaikosaponin-a, 2//-0-acetylsaikosaponin-d, and 2//-0-acetylsaikosaponin-a, respectively."Chaihu," an ordinarily used Chinese traditional medicine, is often utilized to treat commoncold with fever, alternating chill and fever, and the feeling of fullness and oppression in the chest and hypochondria.It has been applied for medical use in China for more than two thousand years."Chaihu" belongs to the Bupleurum genus (Umbeliferae), of which 37 species and 17 variants can be found in China, and 120 species in the world.The pharmacopoeia of the People's Republic of China defines that more than ten species of Bupleurum can be used for medical purposes, apart from Bupleurumchinense DCand B. scorzoneraefolium Willd which are regarded as the standard medical plants.In a previous paper,1} we reported the structural elucidation of a new triterpenoid glycoside named SI isolated from the ground part of B. chinense.Recently, two new species of Bupleurum genus have been found in Yunanprovince, South-west China, and named as B. kunmingense Y. Li et S. L. Pan and B. polyolonum Y. Li et S. L. Pan.It is worth noting that the content of saikosaponins, especially saikosaponin-a and saikosaponin-d in these two species, are remarkably higher than those in B. chinense DC, showing that they can be used more widely as fine materials among