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101.
Ko C Levine B Toniolo A Manohar L Olsen S Werner HJ Martínez TJ 《Journal of the American Chemical Society》2003,125(42):12710-12711
The photoisomerization mechanism of the neutral form of the photoactive yellow protein (PYP) chromophore is investigated using ab initio quantum chemistry and first-principles nonadiabatic molecular dynamics (ab initio multiple spawning or AIMS). We identify the nature of the two lowest-lying excited states, characterize the short-time behavior of molecules excited directly to S2, and explain the origin of the experimentally observed wavelength-dependent photoisomerization quantum yield. 相似文献
102.
Werner Korsatko Christian Knopp Alfred Fuchsgruber Gustav Zigeuner 《Monatshefte für Chemie / Chemical Monthly》1976,35(2):745-755
The structures of tetrahydro-4-phenylspiro([1]benzopyran-2,4(1H)-pyrimidin)-2(3H)-ones and-thiones4 a, b resp., are proved by synthesis. 3-(2-methoxy-3,5-dimethylphenyl)-3-phenylpropionic acid11 b is prepared from 3,4-dihydro-6,8-dimethyl-4-phenylcoumarin10. The lithium salt of11 b reacts with isobutenyl-lithium to 1-(2-methoxy-3,5-dimethylphenyl)-5-methyl-1-phenyl-4-hexen-3-on12 a. 12 a is transferred with urea in acid medium and NH4CNS resp. in a mixture of dihydro-6-[2-(2-methoxy-3,5-dimethylphenyl)-2-phenyläthyl]-4,4-dimethyl-2(1H)-pyrimidinone and-thione13 a, b and tetrahydro-6-[2-(2-methoxy-3,5-dimethylphenyl)-2-phenyläthyliden]-4,4-dimethyl-2(1H)-pyrimidinone and-thione14 a, b resp.14 b leads to13 a, b with H2O2. Heating of13 a, 14 a and14 b resp. with pyridin-HCl leads to the spiro compounds4 a, b. 相似文献
103.
104.
105.
A hybrid heterogeneous catalyst system, which has been synthesized by covalently anchoring oxodiperoxo molybdenum chelate complexes onto the surface of mesoporous MCM-41, is highly active and truly heterogeneous for the liquid-phase epoxidation of cyclooctene with tBuOOH as the oxygen source. 相似文献
106.
Winfried Mientus Hans-Georg Bartel Werner Haberditzl Hans-Joachim Spitzer 《Monatshefte für Chemie / Chemical Monthly》1980,111(3):597-606
A normalization of the wave functions by means of the theoretical exact Multiple-Scattering-(MS)-formalism is discussed within the framework of the SCF-X-SW-method. For the atomic and extramolecular regions the integrals of normalization can be easily determined and the results can be described by the corresponding electronic charges. The calculation of the integral of the interatomic region is problematic. The needful volume integration is only necessary to theGreen's functions of the wave functions and can be solved by means of the residual theory. The further analytical calculation of the surface integrals leads to a complicated formalism which can be numerically evaluated. 相似文献
107.
A synthesis of all possible N-alkylated 2-n-butyl-imidazo[4,5]pyridine isomers is described as well as their structural assignment by 1H NMR spectroscopy. One of these derivatives, 2,-n-butyl-3-[2′- (1H-tetrazol-5-yl)-4-biphenylylmethyl]-3H-imidazo[4,5-b]pyridine 9 is a potent angiotensin II receptor antagonist. 相似文献
108.
Robert Werner Lang 《Helvetica chimica acta》1986,69(4):881-886
The title compound 1 , which can be regarded as a synthetic equivalent of substituted 1,1,1-trifluoroacetone 2 , is prepared by Zn-induced reductive addition of 1,1,1-trichloro-2,2,2-trifluoroethane ( 3 ) to formaldehyde ( 4 ). A brief survey of the scope of this C? C-bond formation leading to a variety of new CF3-containing synthetic building blocks is also given. 相似文献
109.
110.
Diphenylphosphorylazide N3P(O)(OPh)2 reacts with Pt(PPh3)3, Pt(PPh3)2(C2H4), trans-RhCl(CO)(PPh3)2, Ru(CO)3(PPh3)2, CoCl2(PPh3)2 and CuCl(PPh3)2 to give the azido complexes Pt(PPh3)2(N3)R, Pt(PPh3)2(N3)2R2, the urylene complex RhCl(PPh3)2(RNCONR) and the phosphine imine complexes Ru(CO)3(RPPh3)2, CoCl2(RNPPh3)2, CuCl(RNPPh3)2, respectively, (RP(O)(OPh)2). The oxidative addition of n-C6F13SO2N3 to Pt(PPh3)4 and Pt(PPh3)2(C2H4) affords the complexes Pt(PPh3)2(N3)R and Pt(PPh3)2(N3)2R2, respectively, (RSO2C6F13. The compounds are characterized by elemental analysis and by their IR spectra. 相似文献