Studies On Chemical Constituents Of Conyza Canadensis And Conyza Blinii

The genus Conyza (Asteraceae) is composed of more than 80 species,about 25 species of which have been studied chemically. The characteristicconstituents in this genus are clerodane and labdane diterpenoids.JinLongDanCao is the aerial part of C. blinii Lévl. and is distributed insouthwest districts of China. It was recorded in Chinese Pharmacopoeia (1977edition). JinLongDanCao is used in folk medcine for the treatment of chronicbronchitis and other inflammatory diseases. Preliminary pharmacololgical andclinical test have shown that it possesses antibacterial, antiinflammatory,antitussive and expectorant effects. XiaoFeiPeng, the whole herb of C.canadensis, is an annual plant and distributed in many districts of China. Itpossesses haemostatic and diuretic effects and is used for the treatment ofdiarrhoea, dysentery, dropsy and haemoptysis according to foreign literatures.The chemical/active priciples of these two species are not clear so far. Therefore,we have conducted studies on the chemical constituents and activities of the titleplants employing solvent extraction, recrystallization, silica gel columnchromatography, macroporus resin column chromatography, and SephadexLH-20.Eight compounds were isolated from EtOH extract of the whole herbs of C.canadensis. The structures of four compounds are determined using chemicaland spectral methods as epifriedelanol (CCP3), quercetin (CCE1),spinasterol-3-O-β -D-glucopyranoside (CCE2), and quercetin-3-O-α -L-rhamnose (CCE3).Six compounds were isolated from EtOH extract of the aerial part of C.blinii Lévl.. On the basis of NMR spectra, the structures of four compoundswere elucidated as 5,7-dihydroxy-3,8,4'-trimethoxy flavone (CBC3),5,8-dihydroxy-7,3',4'-trimethoxy flavone (CBC4), 5,7-dihydroxy-3,3',4'-trimethoxy flavone (CBC5), 5,7,3'-trihydroxy-8,4'-dimethoxy flavone (CBC6).In this thesis, we also summarized the studies on chemical constitutes andbioactivities of Erigeron and Conyza.In addition, two new glycosidic quinoline alkaloids, 1-methyl-4-methoxy-8-(glucopyranosyloxy) –2 (1H)-quinolinone (1) and 4-methoxy-8-(glucopyranosyloxy)-2(1H)-quinolinone (2), were isolated from the butanol extract ofthe aerial parts of Echinops gmelinii. The chemical components were isolatedby solvent extraction and chromatographic methods, and their structuralelucidation was based on various modern spectral analysis(IR,HR-MS,FAB-MS,P1PHNMR,P13PCNMR,DEPT,P1PH-P1PHCOSY,HSQC,HMQC,HMBC)and acid hydrolysis.