Guided Isolated And Anti-Inflammatorybioactivity Studied Of The Eremophilane-Type Sesquiterpenes From Ligularia Sagitta

Ligularia is a genus of perennial herbaceous plants in Asteraceae family,including approximate 150 species in the world,The vast majority are produced in Asia,only two species are distributed in Europe.There are about 110 species in China,among which 27 species have long been used as folk medicines for the treatment of rheumatic colds,pharyngitis,bruises,tuberculosis,hemoptysis and other diseases.This genus mainly contains secondary metabolites such as eremophilanetype sesquiterpenes,benzofuran sesquiterpenes and pyrrolizidine alkaloids.The eremophilane-type sesquiterpenesare is the most representative secondary metabolite.In order to obtain more eremophilane-type sesquiterpenes with novel structure and well known biological activity,our subject was the Ligularia sagitta from Zhang County,Gansu Province.Using a combination of ¹H NMR and LC-MS,the fractions containing the sesquiterpenes of the eremophilane-type were selected from the methanolic extract of L.sagitta based on the spectral characteristics of the eremophilane-type sesquiterpenes reported in the literature,from which 37 compounds were subsequently separated using various modern separation techniques（silica columns,RP-C18 silica columns,LH-20,HPLC,etc.）,and were determined by various spectroscopic methods(¹H NMR,¹³C NMR,HR-ESI-MS,¹H-¹H COSY,HSQC,HMBC,NOESY,UV,IR,X-ray,etc.)and literature data comparison were used to determine the structures of the fractionated compounds.which included 1 C20 skeleton eremophilane-type sesquiterpenoid,9 C19 skeleton eremophilane-type sesquiterpenoids,18 other skeleton eremophilane-type sesquiterpenoids,2 triterpenes,5 monoterpenes,1 lignan;and 1 coumaroyl tyramine.We studied the antiinflammatory activity of the compounds fractionated and the results indicated that compounds ls-1,ls-4,ls-7,ls-14,ls-17,ls-23,ls-24,ls-25,ls-29,ls-32 and ls-35 showed some anti-inflammatory activity,with compounds ls-17 and ls-23 having smaller IC50 values than those of the positive control.Their IC50 was 11.23 ± 1.67 and 20.88 ± 1.33 μM,respectively.In addition,the structure and origin of 552 eremophilane-type sesquiterpenes reported in the literature,the possible routes of origin of some novel arymorphane sesquiterpenes in the backbone,and the biological activities of some compounds are reviewed in this thesis.