Antioxidant and hepatoprotective effects of ethanol extract of Vitex glabrata on carbon tetrachloride-induced liver damage in rats

This study was aimed at evaluating the antioxidant and hepatoprotective effects of the ethanol extract of Vitex glabrata (EEVG) in a CCl(4)-induced liver damage model in rats; and to isolate and characterise the bioactive constituent from EEVG. Hepatoprotective activity was evaluated by changes in the levels of the serum enzymes viz. AST, ALT, ALP and total bilirubin, and further by histopathological examinations of liver tissues. Antioxidant activity was measured in terms of superoxide dismutase, GSH, lipid peroxidation (LPO), catalase and peroxidase levels in liver homogenate. The pentamethoxy flavonoid artemetin was isolated and characterised from EEVG. Artemetin and EEVG pre-treatment significantly (p?相似文献   

Tuning of crystal phase structure in hydrated WO3 nanoparticles under wet chemical conditions and studies on their photochromic properties

Hydrated tungsten oxide nanoparticles have been synthesized using a simple wet chemical method while varying the concentration of HCl. XRD studies show that the variation in HCl concentration from 1 M to 6 M in the reaction results into gradual change in crystal structure of hydrated WO₃ from hexagonal (WO₃·0.33H₂O) to pure orthorhombic (WO₃·H₂O), through a series of samples with mixed phase of the two indifferent ratios. The similar variations in the degree of hydration and phase variations have also been observed from Raman, FTIR and TGA studies. The average crystallite size of the hydrated WO₃ particles was estimated to be ～26 nm from XRD line broadening and AFM studies showed the formation of spherical shaped particles for all the samples. The photochromic studies were carried out on the composite films of these materials in the polymeric matrix of polyvinyl alcohol (PVA) while exposing to UV light. The composite films show interesting variations in the photochromic behavior depending on the crystal structure of hydrated WO₃ filler. The photochromic behavior has been explained on the basis of EPR spectra of hydrated WO₃.     

Practical synthesis of diastereoisomers by a temperature-guided reversal of diastereoselectivity in the desymmetrization of meso-bridged anhydrides with a chiral oxazolidin-2-one

A perfect temperature-guided diastereoselectivity switch was observed in the desymmetrization of some meso-bridged tricyclic succinic anhydrides with a lithiated chiral 5,5-disubstituted oxazolidin-2-one called SuperQuat. Experimental conditions required for the optimum diastereoselectivity and to obtain the individual diastereoisomers of the SuperQuat linked meso-anhydride opening products with acceptable purity and yield have been established.     

Novel 3,3′-(alkanediyl)bis-(2,2,2-triaryl-1-oxa-2-stiba-3-azabenzo[d]cyclohex-5-enes)

The hitherto unreported compounds of general structure 3,3′-(alkanediyl)bis-(2,2,2-triaryl-1-oxa-2-stiba-3-azabenzo[d]cyclohex-5-ene) have been synthesized in 48-56% yields by the cyclization of the tetrasodium salt of N,N′-bis(2-hydroxybenzyl)-1,2-diaminoethane(II) or of N,N′-bis(2-hydroxybenzyl)-1,3-diaminopropane(II*) with R₃SbBr₂ (R = phenyl, p-tolyl, or mesityl). The tetrasodium salts were prepared by the reactions of the corresponding amines with sodium hydride. The amines (II and II*), in turn, were obtained by the sodium borohydride reduction of N,N′-bis(salicylidene)-1,2-diaminoethane and N,N′-bis-(salicylidene)-1,3,-diaminopropane, respectively. The heterocyclic compounds are air stable and moisture insensitive. These compounds have been characterized by elemental analyses, molecular weight determinations, and by IR, far IR, ¹H, and ¹³C NMR spectral studies. © 1996 John Wiley & Sons, Inc.