title: Isolation, structure elucidation, antioxidative and immunomodulatory properties of two novel dihydrocoumarins from Aloe vera.
abstract: Two new dihydrocoumarin derivatives, compounds 1 and 2, were isolated from Aloe vera. Their structures were determined by X-ray crystallographic diffraction analysis and extensive 1D, 2D NMR spectroscopic data. Both of them evidently showed antioxidant activity against superoxide and hydroxyl radicals. Only 1 obviously exhibited immunomodulatory activity in relation to increasing the phagocytic activity and stimulating the production of superoxide anions in the oxygen respiratory burst of rat peritoneal macrophages.
authors.affiliation: State Key laboratory for Structural Chemistry of Unstable and Stable Species, Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Xiu-feng
authors.initials: XF
authors.lastname: Zhang
authors.forename: Hong-mei
authors.initials: HM
authors.lastname: Wang
authors.forename: Yuan-li
authors.initials: YL
authors.lastname: Song
authors.forename: Li-hua
authors.initials: LH
authors.lastname: Nie
authors.forename: Lan-fen
authors.initials: LF
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Ping-ping
authors.initials: PP
authors.lastname: Shen
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000504:Aloe / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018360:Crystallography, X-Ray; D007155:Immunologic Factors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D008262:Macrophage Activation / Q000187:drug effects; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008958:Models, Molecular; D008968:Molecular Conformation; D012015:Reference Standards; D013237:Stereoisomerism; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D003374:Coumarins; D007155:Immunologic Factors; D013481:Superoxides