Study On The Constituents Of The Leaves Of Crataegus Pinnatifida Bge.var. Major N.E.Br.

Hawthorn leaves are dried leaves of Crataegus pinnatifida Bge.var.major N.E.Br.or Crataegus pinnatifida Bge..Many studies focused on hawthorn leaves'pharmacological effects on cardiovascular system.There are some preparations made fromleaves,such as Yixin ketone,Xinan capsules,etc.,used for treatment of cardiovascular diseases such as hyperlipidemia,coronary heart disease,angina pectoris,and arrhythmia in clinic.Total flavonoids are regarded as main constituents of these hawthorn leaves preparations,but their composition and structure-activity relationship are still not clear so far.Meanwhile,it is found that hawthorn leaves also contains other types of compounds,especially some terpenoids,due to our previous analysis work.Literature surveys show that terpenoids are mostly found in hawthorn fruits,and there are few reports on terpenoids from hawthorn leaves.Therefore,it is necessary to perform a systematic study on chemical composition of hawthorn leaves.Through this work,we can obtain a series of compounds from hawthorn leaves,and explore the structure-activity relationship between these compounds and cardiovascular activities.Thirty-five compounds were finally isolated and purified from the 70%Et OH extract of hawthorn leaves?Crataegus pinnatifida Bge.var.major N.E.Br.?by using various chromatographic columns on AB-8 resin,silica gel,Sephadex LH-20 and ODS C₁₈,as well as the semi-preparative HPLC,and their structures were elucidated by MS,¹D and ²D NMR spectra.Among the above isolates,crataegunin A_11,crataegunin B_12,crataegunin C_13,crataegunin Dwere identified as new compounds,and 10,15,16,18,21,23-26,29,31 and 34 were obtained from hawthorn leaves for the first time.The structure types of the compounds include flavonoids?flavonoid glycosides?,flavanols and their dimer derivatives,triterpenoids,monoterpenoids,organic acids,etc.,which have established a good material foundation for pharmacological activity research.