摘要:

AbstractThe synthetic studies for some known modulators of metabotropic glutamate receptors (mGluRs) such as (S)‐αM4CPG, (1S,3R)‐ACPD,L‐CCG‐I are described. Based on the structure of αM4CPG several new conformationally constrained analogues are design ed and synthesized. Among them APICA is a selective antagonist for group II mGluRs. Also, a new benzolactam‐V8 analogue is found to have better isoform‐selectivity for protein kine C family. Three different protocols for synthesizing benzolactam‐VS analogues are developed to meet the requirement for delivering more an

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160402

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractSolubilities of ribidium tetraphenylborate in water, methanol, ethanol, 1‐propanol, 1‐butanol, 1‐pentanol, 1‐hexanol and l‐octanol at 288.15, 298.15, 308.15, 318.15, 328.15 K have been determined by spectrophotometry. The standard Gibbs energy of transfer of ribidium tetraphenylborate from water to straight‐chainn‐alkanols and the primary medium effect of rubidium tetraphenylborate from 288.15 to 328.15 K have been calculated. Furthermore, the contribution of microscopic interactions to the standard Gibbs energy of transfer of rubidium tetraphenylborate in calculated

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160403

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe geometries, heats of formation and electronic structures of 15 azido‐derivatives of 1,2,3‐TNB (I), 1,2,4‐TNB (II) and 1,3,5‐TNB (III) have been studied using quantum chemical AM1 method at HF level. The effect of azido substitution on the structures and properties of TNBs has been discussed and the relative stability of the title compounds has been established. The processes of the decomposition of the title compounds by breaking C‐NO2, C‐N3and CN‐N2bonds are investigated at UHF‐AM1 level. It is shown that the decomposition of the title compounds may be initiated by the cleavage of both C

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160404

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractA new quantum scattering approach (linear combination of arrangement channels‐scattering wavefunction, LCAC‐SW) proposed by Deng and his co‐workers is used to calculate collinear state‐to‐state reaction probabilities for the F + H2(v) → HF(v') + H system. Several interesting problems such M threshold energy, compound states and enhance by translational energy of the reactants and the vibration excitation of products are discussed and they are compared with other theoretical investigations reported in the literature. It is shown that the LCAC‐SW approach is the successful one of quantum scatt

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160405

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractSodium or quaternary ammonium modified Nafion membranes in forms of Nafion‐Na+, Nafion‐NMe+4:, Nafion‐NEt+4and Nafion‐NBu+4: have bean prepared by neutralizing Nafion‐H+membrane with NaOH or tetraalkylammonium hydroxide aqueous solution. Intramolecular excimer formation and fluorescence polarisation methods using 1,3‐di(1‐pyrenyl)propane and acridine orange‐as probes respectively have been employed for measurements of the microviscosity within those modified Nafion membranes. Results show that the probes are located in the fluorocarbon/water interface in the cluster of the membranes and the microviscosities around the probe molecules an in the range ofca. 120–1200 cp and increase in the order of Nafion‐Na+

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160406

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe protonation process of two DTPA bis(amide) derivatives, DTPA‐BDMA and DTPA‐BDEA, was studied by using1H NMR titration and MOPAC calculation. Their protonation process was proposed in the order of the central amine, the terminal amines, the central carboxyl, the terminal carboxyl, the other terminal carboxyl and central amine. During the protonation of the terminal amine, them existed a large fraction of proton transfer from the central amine to the other terminal am

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160407

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe dynamics of the NH + H → N + H2reaction has been investigated by means of the 3D quasiclassical trajectory approach by using the LEPS potential energy surface. The calculated rate coefficient is in good agreement with the experimental value. The reaction was found to occur via a direct channel. The product H2has a cold excitation of rotational state, but has a reverse distribution of the vibrational state with a peak atv=l. Based on the potential energy surface and the trajectory analysis, the reaction mechanism has been explained successfull

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160408

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe title polymer PCuS4P5was synthesied by reaction of 2,3‐dicyano‐5,6‐dihydro‐1,4‐dithiin, pyromellitic dianhydride and urea with cuprous salt in optimized gentle method. The structure and properties of the PCuS4P5were characterized by elemental analysis, X‐ray powder diffraction, IR, UV‐Vis, fluorescence and EPR spectra and variable‐temperature magnetic susceptibility. The polymer is black sublimable crystallite and the degree of polymerisation has been found to ben>4. The PCuS4P5in H2SO4exhibits intensive absorption bands at 236, 342, 656 and 767 nm and intensive fluorescence band at 410 nm or 464 nm under the excitation of the ultraviolet light of a determined wavelength at room temperature. It has been found that the polymer exhibits a weaker antiferromagnetic interaction (J=−2.1 cm−l, μaff=1.68 B.M.) with an apparent spinS<1/2 in the ground state and its conductivity σ298Kis 1.01×

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160409

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe stability constants of the binary ML2+and ternary M(ATP)L2−complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+or Cd2+, have been determined by potentiometric pH titration in aqueous solution atI=0.1 mol/L (NaClO4),T=25°C. The stability of the ternary complexes characterized by ΔlogKM=logKM(ATP)LM(ATP)L‐ logKMMLcorresponding to the equilibrium M(ATP)2−+ ML2+= M(ATP)L2−+ M2+in higher than what would be expected on statistical grounds. The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4–.1H NMR studies of Zn2+/ATP4−/L confirm the presence of stacking in the ternary complexes. It is concluded that the strength of the intramolecular stacking interaction ia dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge. Possible implications an disc

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160410

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractIn this paper new heterocyclic compounds 5‐[(1,1‐dimethyl)ethyl]‐3‐aryl‐(1H‐l,2,3‐triazol‐1‐yl)‐5‐isoxazolodinols were obtained by the reaction of vinyl triazole derivatives with hydroxylamine hydrochloride under the action of sodium carbonate. The biological tests indicate that they had plant‐gro

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160411

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY