Analysis Of Alkaloid Structure In The Fruits Of Macleaya Cordata (willd) R.Br. Based On Nuclear Magnetic Resonance And Mass Spectrometry

Chemical components were isolated from the fruits of Macleaya cordata (willd)R.Br. which belonging to macleaya family, and the structure of those compounds were identified. On this basis, the tandem mass spectrometry (MS/MS) fragmentation pathways of8types of alkaloids which exist in biosynthetic pathway of isoquinoline alkaloids were investigated in order to systematically speculation the structure of alkaloids in Macleaya cordata and Macleaya microcarpa.22compounds were isolated from fruits of Macleaya cordata by the modern chromatographical methods. The structure of14compoounds, including6-Cyanodihydrosanguinarine(1),6-Methylo1-7,8-demethyldihydro chelerythrine(2),2,3-Methylenedioxy-10,12-dimethyl-7,8,9,10-tetrahydrobenzoquinoline(3),(2,3-Methylenedioxy-7,10-dimethyl-8-carboxyl-benzo-quinoline(4),13,14-Dehydrogen-N-methylcoptisine(5), N-methylcanadine (6),14-Hydroxyl-N-methylcoptisine(7),14-Hydroxyl-N-methyl-canadine(8), Berberine (9), Chelerythrine(10), Dihydro-chelerythrine)(11),6-Acetonyldihydrosanguinarine (12),6-Acetonyldihydro-chelerythrine(13),p-Sitosterol (14), were determined by nuclear magnetic resonance (NMR) and mass spectrometry(MS). Among those alkaloids,3and4are new compounds,1and5are new nature products, and6,7,8are repoeted for the first time in Macleaya cordata.A new method was established for speculation and identification the alkaloids in Macleaya cordata on the basis of MS/MS fragmentation patteren of8types of alkaloids which exist in biosynthetic pathway of isoquinoline alkaloids and isolated compounds. In this method, the alkaloid structure is divided into three parts, namely, the skeleton, the substitute groups and the linkage sites between the skeleton and substitute groups. The skeleton is determined mian from MS/MS fragmentation patterns. The substitute groups are determined through a screening procedure which developed by our laboratory and from the MS/MS fragmentation pathways. The linkage sites are deduced from the MS/MS fragmentation behavior and from the biosynthetic pathway of isoquinoline alkaloids.21alkaloids are identified,10of them are reported for the first time in fruits of Macleaya cordata, and41alkaloids are identified,33of them are reported for the first time in fruits of Macleaya microcarpa.