Study On The Chemical Constituents Of The Aboveground Part Of Eupatorium Japonicum Thunb.

Eupatorium japonicum Thunb.is a perennial herb in the Eupatorium genus of the family Compositae.According to the record,it has been used in 12 ethnic minorities in China,it possesses various biological activities such as relieve pain,arnica extract and detumescence.In clinical application,tujia medicine maker also concluded that Eupatorium japonicum Thunb.has anti-fatigue,aphrodisiac,treatment of pain,upper respiratory infection and gingivitis,etc.There are few reports on chemical constituents of Eupatorium japonicum Thunb.,the results show that only a small amount of phenylpropanoids and sesquiterpenoids be isolated.Therefore study on its chemical constituents is of great significance for the further development and clinical application.Fourteen compounds were isolated from the 70% ethanolic extractives of the aboveground part of Eupatorium japonicum Thunb.by using a variety of column chromatographies of silica gel,Sephadex LH-20 gel and preparative HPLC.Their chemical structures were elucidated as taraxasteryl acetate(1),9-O-angeloyl-8,10-dehydrothymol(2),Di-n-butyl ortho-phthalate(3),8-hydroxyl-9-angeloyloxythymol(4),9-acetoxythymol 3-O-tiglate(5),coumarin(6),Eupatobenzofuran(7),stigmasterol(8),9-angeloyloxythymol(9),Euponin(10),hydrocoumaric acid(11),4-methylsalicylic acid(12),7-hydroxy-4-methyl isochroman-1-one(13),2,3-dihydro-3,5-dimethyl benzofuran(14)by extensive spectroscopic analysis including MS,NMR,etc.As a result,1?14 are firstly isolated from Eupatorium japonicum Thunb.,6,11 and 13 are firstly isolated from Eupatorium,12 is firstly isolated from Compositae,14 is firstly isolated from natural resource.The volatile oil was extracted by steam distillation,soxhlet extraction and ultrasonic assisted extraction respectively,and analyzed by GC-MS combined with retention index.The main components are ?-caryophyllene(18.35%),humulene(5.65%),macrogeranyl D(6.95%),sesquiphellandrene(10.30%),2-isopropyl-5-methyl phenyl-2-methyl butene-2-acry lies(13.38%),coumarin(4.51%).The composition and yield of volatile oil extracted by different extraction methods were different.By dual wavelength TLC scanning method for determination of taraxasteryl acetate in the leaves of Eupatorium japonicum Thunb.was 0.342%,RSD% is 1.62 %.And the content was considerable,which might be the main chemical component in the leaves.The study on Eupatorium japonicum Thunb.proved factual foundation and encriched the chemical study for the extensive use of Eupatorium japonicum Thunb.