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81.
Marcia I. Dawson Rebecca L.-S. Chan Ian S. Cloudsdale Wesley R. Harris 《Tetrahedron letters》1981,22(29):2739-2742
Tris(catecholcarboxamide) ligands were covalently linked to poly(vinyl amine—vinyl sulfonate sodium salt), and the iron binding capacity of the resultant polymers was found to exceed that of transferrin. 相似文献
82.
Gray DE Messer D Porter A Ferguson S Harris RK Clark AP Algaier JW Overstreet JD Smith CS 《Journal of AOAC International》2005,88(6):1613-1620
We report here a liquid chromatography (LC) method with inline ultraviolet/evaporative light scattering (UV/ELS) detection for the simultaneous quantification of the terpenelactones and flavonol aglycones in a single sample of hydrolyzed Ginkgo biloba extract (GBE). The sample is hydrolyzed by a rapid and convenient oven heating method for 1 h at 90 degrees C with 10% hydrochloric acid. The 1 h hydrolysis was found to be equivalent to the 2.25 h reflux treatment for dry powder extract, where total flavonol glycosides were 28.4 and 28.1%, respectively. Acceptable precision was achieved for total terpenelactones [relative standard deviation (RSD) = 4.8%] by ELS detection, and total flavonol aglycones (RSD = 2.3%) by UV detection. The analytical range was 1.5 to 7.3% (w/w) for the individual terpenelactones (ELS) and 2.5 to 15.0% (w/w) for the individual glycosides (UV) calculated from the aglycones quercetin, kaempferol, and isorhamnetin. This improved method allows for the first time high throughput sample preparation coupled with the quantification of the predominant compounds generally used for quality control of GBE in a single assay. 相似文献
83.
84.
J. B. Hudson E. A. Graham L. Harris M. J. Ashwood-Smith 《Photochemistry and photobiology》1993,57(3):491-496
The novel furoisocoumarin, coriandrin, which was found recently to possess an interesting combination of photobiological properties, was investigated for antiviral activity in the presence and absence of UVA (long-wavelength ultraviolet radiation). In contrast to results obtained with other antiviral furocoumarins, such as 8-MOP (8-methoxypsoralen), coriandrin was much more phototoxic to the RNA-virus Sindbis virus than to the DNA-virus murine cytomegalovirus, although both viruses were substantially more sensitive to this compound than they were to 8-MOP. Human immunodeficiency virus, HIV-1, was also susceptible to coriandrin + UVA. Another unexpected finding was that viruses without membranes were completely resistant to coriandrin. This suggests that a membrane component was a target for the compound. The antiviral activity of coriandrin was profoundly inhibited by serum components in the reaction mixtures, which suggests that the compound may have a strong affinity for certain protein or lipid materials, although maximal interference was only obtained when all components of the reaction mixture, virus, coriandrin and serum, were irradiated simultaneously. Thus it appears that coriandrin has unusual antiviral properties that would not be predicted from its chemical similarity to furocoumarins. 相似文献
85.
C. Glidewell G.S. Harris H.D. Holden D.C. Liles J.S. McKechnie 《Journal of fluorine chemistry》1981,18(2):143-154
Fluorination of triphenylarsine oxide by aqueous hydrogen fluoride (1–40%) in the absence of glass readily gives triphenylarsine difluoride. When the reaction with dilute (1%) aqueous hydrogen fluoride is carried out in borosilicate glass apparatus, the glass participates in the reaction resulting in the formation of the crystalline 2:1 adduct 2Ph3AsO·HBF4. Crystals of this compound are monoclinic, 21/, = 12.926(4), = 17.819(6), = 14.994(4) Å, β = 98.97(3)°, Z = 4. The structure contains cations [(Ph3AsO)2H]+ in which O is 2.44(2)Å, and anions BF4?. 相似文献
86.
The vibrational population distribution of X 1Σ(υ′' = 0 through ν′' = 7) BaO formed in the reaction Ba + O2 at 0.3 torr has been measured by laser induced photoluminescence intensities. On the basis of the assumed similarity between the Ba + O2 and Ba + N2O reactions, these data suggest that a population inversion may exist between A 1Σ(ν′ = 1) and X 1Σ(υn = 7) BaO formed in the latter reaction at ≈ 16 torr. 相似文献
87.
88.
A series of phenylated dihydrophthalimides has been synthesized by the Diels-Alder reaction of tetraphenylcyclopentadienone with maleimide, N-phenylmaleimide, and N,N'-o-, -m-, and -p-phenylenedimaleimide. Subsequent dehydrogenation of these compounds yielded the corresponding phenylated phthalimides. These phthalimides were also obtained in one step when the initial reactions were carried out in refluxing nitrobenzene. 相似文献
89.
The bidentate dithiomethyl ester complex, RuI(CO)(PPh3)2 (CS2Me) reacts with primary amines affording a series of novel dimeric isonitrile complexes, [RuI(CO)(CNR)(PPh3)2SH]2. 相似文献
90.
William A. Feld B. Ramalingam Frank W. Harris 《Journal of polymer science. Part A, Polymer chemistry》1983,21(2):319-328
Four aromatic dinitro compounds containing oxyethylene units 1,2-bis(4-nitrophenoxy)ethane, bis(2)-(4-nitrophenoxy)ethyl ether, 1,2-bis(2)-(4-nitrophenoxy)ethoxy)ethane, and bis(2-(2-(4-nitrophenoxy)ethoxy)ethyl) ether were prepared by an aromatic nucleophilic substitution reaction that involved 1-fluoro-4-nitrobenzene and the appropriate oxyethylene glycol. Each of the dinitro compounds could be reduced chemically or catalytically to produce the diamines 1,2-bis(4-aminophenoxy)ethane, bis(2-(4-amino-phenoxy)ethyl ether, 1,2-bis(2-(4-aminophenoxy)ethoxy)ethane, and bis(2-(2-(4-aminophenoxy)ethoxy)ethyl) ether. Polymerization of the diamines was carried out in m-cresol with toluene as an azeotroping agent. Polymides derived from 5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis-1,3-isobenzofuradione exhibited good solubility in chlorinated solvents, glass transition temperatures as low as 140°C, as evidenced by viscous flow, and good thermal stability; a 5% weight loss generally occured at greater than 450°C. Isothermal aging studies conducted at 600°F(315°C) for 200 h indicated that weight loss is directly related to oxyalkylene chain length–10% for the shortest and 50% for the longest chain. 相似文献