3465-72-3Relevant academic research and scientific papers
Inhibition of histidine ammonia lyase by 8-methoxypsoralen and psoralen-oxidized photoproducts
Reilly, John T.,Troester, Kyle A.,Tyner, Trista T.,Vitale, Dominick A.,Risher, Tiffiany R.
, p. 1272 - 1277 (2010)
The effect of 8-methoxypsoralen-UVA therapy on the catalysis of histidine to trans-urocanic acid by histidine ammonia lyase (HAL, EC 4.3.1.3) was examined using an enzymatic assay from Sigma-Aldrich where the growth of the trans-urocanic acid peak at 277 nm was monitored. A Rayonet Photochemical Mini Reactor (Model RMR-600) equipped with eight, 3500 ? light sources and a custom UVA filter (Model S-BAL3 2.9 mm), from the Solar Light Company, were used to expose various reaction mixtures to broadband UVA light and UVA/UVB light. A UV-Vis spectrophotometer (Model Shimadzu UV 2540) with a temperature-controlled cell holder (Model TCC240) was used to monitor the growth of the trans-urocanic peak. Results of dark-binding experiments of 8-methoxypsoralen in denatured ethanol indicate no inhibition of enzyme activity due to ethanol but noncompetitive inhibition due to 8-methoxypsoralen. The effects of preirradiated 8-methoxypsoralen, with both broadband UVA and UVA/UVB, indicate that inhibition was due to psoralen-oxidized photoproducts. Inhibition of HAL was found when exposed to broadband UVA/UVB and to a lesser extent when exposed to broadband UVA.
Evidence for azidyl radical initiated olefin isomerization. One-way isomerization of (Z)-Urocanic acid
Kpissay, Armah,Kuhl, C. Nicole,Mohammad, Taj,Haber, Ken,Morrison, Harry
, p. 8435 - 8438 (1997)
(Z)-Urocanic acid (cis-UA), unlike its (E) isomer (trans-UA), undergoes photoisomerization in the presence of nitro blue tetrazolium (NBT2+) and sodium azide. Evidence is presented that the photoisomerization involves the reversible addition of the azidyl radical to the double bond.
Iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabled aldehyde C-H methylation
Gong, Pei-Xue,Xu, Fangning,Cheng, Lu,Gong, Xu,Zhang, Jie,Gu, Wei-Jin,Han, Wei
supporting information, p. 5905 - 5908 (2021/06/18)
A practical and general iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabling aldehyde C-H methylation for the synthesis of methyl ketones has been developed. This mild, operationally simple method uses ambient air as the sole oxidant and tolerates sensitive functional groups for the late-stage functionalization of complex natural-product-derived and polyfunctionalized molecules.
A solid oxide fuel cell fuel electrode material
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, (2007/10/04)
PROBLEM TO BE SOLVED: To provide a material capable of showing excellent conductivity as a fuel cell material of a solid oxide fuel cell. SOLUTION: In the electrode material used for a fuel electrode of the solid oxide fuel cell and related to its manufacturing method, the material has a composition including a nickel oxide as a first component, a zirconium oxide as a second component, and at least one kind among a scandium oxide, an yttrium oxide, and a calcium oxide as a third component, and the material is powder wherein a pore volume is 0.1 cm3/g or larger and a pore rate is 20% or higher. COPYRIGHT: (C)2009,JPOandINPIT
Synthesis of N-methyl urocanates of hydroxyderivatives of isocembrol
Valeev,Salikhov,Krasnoslobodtseva,Sharipov,Spirikhin,Tolstikov
, p. 143 - 148 (2008/03/11)
Alcohols were prepared by stereospecific hydroxylation of isocembrol and were esterified into N-methylurocanates, proposed biomimetics of taxol.
Die Rolle von Dehydroalanin in der Katalyse durch Histidin-Ammoniak-Lyase
Langer, Martin,Pauling, Andrea,Retey, Janos
, p. 1585 - 1587 (2007/10/02)
Stichworte: Dehydroalanin.Enzymkatalyse.Histidin.Reaktionsmechanismen
Thermochemistry of the reactions between adenosine, adenosine 5'-monophosphate, inosine, and inosine 5'-monophosphate; the conversion of L-histidine to (urocanic acid + ammonia)
Larson, J. W.,Tewari, Y. B.,Goldberg, R. N.
, p. 73 - 90 (2007/10/02)
Results of equilibrium and calorimetric measurements are reported for a series of enzyme-catalyzed reactions involving the deamination of adenosine 5'-monophosphate (AMP), adenosine, and L-histidine, and the dephosphorylation of AMP and inosine 5'-monophosphate (IMP).These measurements have been analyzed with a model which describes the complex equilibria in solution.The results obtained are: ΔrHmo = -(49.6 +/- 0.5) kJ*mol-1 for AMP2-(aq) + H2O(l) + H+(aq) = HIMP2-(aq) + NH4+(aq); ΔrHmo = -(49.4 /- 0.7) kJ*mol-1 for adenosine(aq) + H2O(l) + H+(aq) = inosine(aq) + NH4+(aq); ΔrGmo = -(13.0 +/- 0.4) kJ*mol-1, ΔrHmo = (0.9 +/- 0.4) kJ*mol-1, and ΔrSmo = (47 +/- 2) J*K-1*mol-1 for AMP2-(aq) + H2O(l) = adenosine(aq) + HPO42-(aq); ΔrGmo = -(12.6 +/- 0.1) kJ*mol-1, ΔrHmo = (1.2 +/- 0.2) kJ*mol-1, and ΔrSmo = (48 +/- 1) J*K-1*mol-1 for HIMP2-(aq) + H2O(l) = inosine(aq) + HPO42-(aq); and ΔrGmo = -(2.5 +/- 0.7) kJ*mol-1, ΔrHmo = (7.6 +/- 0.8) kJ*mol-1, and ΔrSmo = (34 +/- 4) J*K-1*mol-1 for L-histidine(aq) = urocanate-(aq) + NH4+(aq).These results are discussed in relation to both thermodynamic-cycle calculations involving these substances and other reactions of a chemically similar nature.
Polyphosphazene polymers and their preparation
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, (2008/06/13)
This invention relates to new polyphosphazene polymers and a process for their preparation. The new polyphosphazenes have different side chains coupled to the phosphorus atoms of the -N=p- main chain via nitrogen atoms, said side chains including imidazolyl groups, aromatically substituted groups and, if required, non-aromatically substituted groups. The polymers may be used in several forms as implant for gradual drug release.
