Flavanones Of Artemisia Ordosica Kraschen And Elsholtzia Bodinieri Vaniot & Their Scavenging Activities To Free Radicals

In this paper, six flavanones were isolated from Artemisia OrdosicaKraschen(Compositae) and Elsholtzia Bodinieri Vaniot(Labiatae). The free radicalscavenging activities of them were studied and compared with flavonoids byspectrophotometric method. The structure-activity relationships (SAR) weresummarized. Isolation and structural elucidation of these compounds were brieflyintroduced. Two crystals of 5,4′-dihydroxy-7-methoxyflavanone isolated fromArtemisia Ordosica Kraschen were studied by X-ray diffraction crystallography. Themain contents are as follows:1. Review on development of natural flavanones The research of flavanones was summarized in recent ten years, includingisolation,extraction,structural elucidation,determination,activity and synthesis.2. Isolation and structural elucidation of flavanones in A. Ordosica Kraschen & E. Bodinieri Vaniot The chemical constituents of A. Ordosica Kraschen and E. Bodinieri Vaniot wereInvestigated systemically. Six flavanones were isolated and their structures wereelucidated by UV,IR,MS,NMR and chemical methods. These compounds were5-hydroxy-7,4′-bimethoxyflavanone (â… ),5,4′-dihydroxy-7-methoxyflavanone(â…¡),5,3′,4′-trihydroxy-7-methoxyflavanone(â…¢),3,5,7-trihydroxy-4′-methoxyflavanone(â…£),5,7-dihydroxy-4′-methoxyflavanone(â…¤) and 5,3′,4′-trihydroxyflavanone-7-O-glycoside (â…¥).Two crystals of 5,4′-dihydroxy-7-methoxyflavanone were acquiredand analyzed by X-ray diffraction crystallography.3. Anti-free-radical activities of flavanones in A. Ordosica Kraschen & E. Bodinieri Vaniot The free radical scavenging activities of flavanones isolated from A. OrdosicaKraschen and E. Bodinieri Vaniot were investigated and compared with flavonoids byspectrophotometric method. Their scavenging activities of DPPH radicals,superoxideanion radicals and hydroxyl radicals were investigated. The results show thatscavenging activities of these compounds were determined by the amount and locationof phenol hydroxyl substitute. Ortho-substituting hydroxyl in the B-ring is important toDPPH· and ·OH. As to O₂^- , The 2,3-double bond in the C-ring is much important. Thesubstitute of 7-Glc effects scavenging activities of flavonoids and flavanones.