955 resultados para 1,3,4-triazólio-2-tiolato


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A novel organotin complex, EtPhSnCl(2) . 2HOC(10)H(6)CH = NC6H1OCH3 was synthesized, and its crystal structure was determined by X-ray diffraction method. The crystal is triclinic, belonging to space group, with unit cell parameters a = 1.150 8(5) nm, b = 1. 153 1(5) gm, c = 1. 004 6 (3) nm, alpha = 94. 15 (3)degrees, beta = 115.47 (3)degrees, r = 85. 94 (4)degrees, V = 1199 7(1) nm(3), Z=2, D-c=1.68 g/cm(3), mu=13. 20 cm(-1), F(000)=618 for 4 131 reflections tions. R=0. 047, R(w)=0. 047. The ligand coordinates to tin atom via phenolic oxygen atom. The complex has a distored trigonal bipyramidal structure, the phenolic oxygen atom of the ligand and one of two chlorine atoms occupy the axial position. The distance between noncoodinated nitrogen atom with phenolic oxygen atom is 0. 257 4 nm, which indicates that the intramolecular hydrogen bond of Schiff base ligand is retained in the complex.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The compounds O(CH2CH2C5H4)(2)Ln(THF)(2) [Ln = Sm(1), Yb(2)] were synthesized by the reduction of O(CH2CH2C5H4)(2)LnCl with sodium metal in tetrahydrofuran (THF) at room temperature. Recrystallization of 2 from dimethoxyethane (DME) produced the single-crystal O(CH2CH2C5H4)(2)Yb(DME) (3) whose structure has been determined by an X-ray diffraction study. The crystals are orthorhombic, space group Pcab, with a = 14.168(4), b = 13.541(6), c = 19.314(8) Angstrom, Z = 8, D-calc. = 1.66 g cm(-3).

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Gas permeability coefficients of a series of aromatic polyetherimides prepared from 1,4-bis(3,4-dicarboxyphenoxy) benzene dianhydride (HQDPA) and four (methylene dianiline)s with a methyl side group to H-2, CO2, O-2, N-2, and CH4 were measured under 7 atm and within a temperature range from 30 to 150 degrees C. The gas permeabilities and permselectivities of these polymers were compared with those of the HQDPA-based polyetherimides from methylene dianiline (MDA) and isopropylidene dianiline (IPDA). The number and position of the methyl side groups on the benzene rings of the diamine residues strongly affect the gas permeabilities and permselectivities of the HQDPA-based polyetherimides. The gas permeability of the polyetherimide progressively increases with an increase in the number of the methyl side groups. Both the gas permeability and permselectivity of the polyetherimides with methyl side groups are higher than those of HQDPA-MDA. The polyetherimide prepared from 3,3'-dimethyl 4,4'-methylene dianiline (DMMDA1) possesses both higher permeability and permselectivity than the polyetherimides prepared from 2,2'-dimethyl 4,4'-methylene dianiline (DMMDA2). However, two of the polyetherimides prepared 2,2',3,3'-tetramethyl 4,4'-methylene dianiline (TMMDA1) or 2,2', 5,5'-tetramethyl 4,4'-methylene dianiline (TMMDA2) possess almost the same gas permeability and permselectivity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

二苯乙炔和金属锂在乙醚中反应得到1,4-二锂四苯基丁二烯,再与无水氧化希土反应得到了两种系金属条-2,3,4,5-四苯基环戊二烯环状化合物。通过元素分析、红外光谱、核磁共振谱、热失重及电子能谱的分析,对所合成的化合物进行了表征;并对化合物的水解产物作了红外光谱、质谱和核磁共振谱分析,确认下列两种化合物的存在:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new lead(II) phosphonate, Pb[(PO3)(2)C(OH)CH3]center dot H2O (1) was hydrothermally synthesized and characterized by IR, elemental analysis, UV, TGA, SEM, and single crystal X-ray diffraction analysis. X-ray crystallographic study showed that complex 1 has a two-dimensional double layered hybrid structure containing interconnected 4- and 12-membered rings and shows an unusual (5,5)-connected (4(7) . 6(3)) (4(8) .6(2)) topology. (C) 2008 Elsevier B.V. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

N'-(4-fluorobenzylidene)-2-(1H-1 2,4-triazole-1-yl) acetohydrazide was synthesized by the reaction of 4-fluorobenzaldehyde with 2-(1H-1 2,4-triazole-1-yl) acetohydrazide. The structure was confirmed via elemental analysis, MS, H-1 NMR, IR, and X-ray diffraction. It crystallized in a monoclinic system with space group P2 (1) a = 0.4905 (1) nm, b = 0.8160 (2) nm, c = 1.4105 (3) nm, beta = 93.33 (3)degrees, Z = 2, V = 0.5636 (2) nm(3), D-c = 1.457 Mg/m(3), mu = 0.112 mm(-1), F(000) = 256, and final R-1 = 0.0685. Several intermolecular hydrogen-bond interactions existed in the crystal structure, facilitating the stabilization of the compound.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The X-ray crystal structures of two crystalline forms of 5-(2,3,5-trichlorophenyl)-2,4-diaminopyrimidine, C10H7Cl3N4 (code name BW1003C87) (I) and (II), have been carried out at liquid nitrogen temperature. A detailed comparison of the two structures is given. Both are centrosymmetric, with structure (I) in the triclinic space group P (1) over bar unit cell a = 6.4870(10), b = 9.216(2), c = 12.016(2) angstrom, alpha = 75.78(3)degrees, beta = 89.95(3)degrees, gamma = 83.45(3)degrees, V = 691.5(2) angstrom(3), Z = 2 and density (calculated) = 1.544 Mg/m(3); and (II) in the monoclinic space group P2(1)/c, unit cell a = 12.000(2), b = 7.518(2), c = 13.450(3) angstrom, beta = 97.87(3)degrees, V = 1202.0(5) angstrom(3), Z = 4, Density (calculated) = 1.600 Mg/m(3). Structure (I) includes a solvated CH3OH in the lattice. Final R indices [I > 2sigma(I)] are R1 = 0.0427, wR2 = 0.1075 for (I) and R1 = 0.0487, wR2 = 0.1222 for (II). R indices (all data) are R1 = 0.0470, wR2 = 0.1118 for (I) and R1 = 0.0623, wR2 = 0.1299 for (II). 5-Phenyl-2,4 diaminopyrimidine and 6-phenyl-1,2,4 triazine derivatives, which include lamotrigine (3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazine), have been investigated for some time for their effects on the central nervous system. Both lamotrigine and 5-(2,3,5-trichlorophenyl)-2,4-diaminopyrimidine (code name BW1003C87), the subject of the present study, are anticonvulsant as well as neuroprotective in models of brain ischaemia and in a model of white matter ischaemia. BW1003C87 is a sodium channel blocker which also reduces the release of the neurotransmitter glutamate. The three dimensional structures reported here form part of a newly developed data base for the detailed investigation of members of this drug family and their biological activities.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new generation of water soluble tetrazolium salts have recently become available and in this study we compared a colorimetric assay developed using one of these salts, 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8), with a previously developed 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide(XTT) colorimetric assay to determine which agent is most suitable for use as a colorimetric indicator in susceptibility testing. The MICs of 6 antibiotics were determined for 33 staphylococci using both colorimetric assays and compared with those obtained using the British Society for Antimicrobial Chemotherapy reference broth microdilution method. Absolute categorical agreement between the reference and test methods ranged from 79% (cefuroxime) to 100% (vancomycin) for both assays. No minor or major errors occurred using either assay with very major errors ranging from zero (vancomycin) to seven (cefuroxime). Analysis of the distribution of differences in the 1092 dilution MIC results revealed overall agreement, within the accuracy limits of the standard test ( 1 1092 dilution), using the XTT and WST-8 assays of 98% and 88%, respectively. Further studies on 31 ESBL-producing isolates were performed using the XTT method with absolute categorical agreement ranging from 87% (nitrofurantoin) to 100% (ofloxacin and meropenem). No errors were noted for either ofloxacin or meropenem with overall agreement of 91%. The data suggests that XTT is more reliable and accurate than WST-8 for use in a rapid antimicrobial susceptibility test. (c) 2007 Elsevier B.V. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The Heck arylation of 2-methylprop-2-en- I -ol in ionic liquids and organic solvents is reported using a range of homogeneous and heterogeneous palladium catalysts. Higher activity is observed in the ionic liquid media compared with N-methyl pyrrolidinone and under solventless conditions. The ionic liquid-catalyst system may be recycled easily with little loss in activity, although significant palladium leaching from the heterogeneous catalyst was observed. In the case of Trans-bis(2,3-dihydro-3-methylbenzothiazole-2-ylidene)diiodopalladium (11) reported to be highly active for this transformation, significant induction petiods were observed indicating that nanoparticles may be responsible for the catalysis. Using the ionic liquid Heck reaction, a recyclable synthesis for the fragrance beta-Lilial((R)) has been developed. (c) 2004 Elsevier B.V. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The synthesis of the C2-symmetrical ligand 1 consisting of two naphthalene units connected to two pyridine-2,6-dicarboxamide moieties linked by a xylene spacer and the formation of LnIII-based (Ln1/4 Sm, Eu, Tb, and Lu) dimetallic helicates [Ln2 · 13] in MeCN by means of a metal-directed synthesis is described. By analyzing the metal-induced changes in the absorption and the fluorescence of 1, the formation of the helicates, and the presence of a second species [Ln2 · 12] was confirmed by nonlinear- regression analysis. While significant changes were observed in the photophysical properties of 1, the most dramatic changes were observed in the metal-centred lanthanide emissions, upon excitation of the naphthalene antennae. From the changes in the lanthanide emission, we were able to demonstrate that these helicates were formed in high yields (ca. 90% after the addition of 0.6 equiv. of LnIII), with high binding constants, which matched well with that determined from the changes in the absorption spectra. The formation of the LuIII helicate, [ Lu2 · 13 ] , was also investigated for comparison purposes, as we were unable to obtain accurate binding constants from the changes in the fluorescence emission upon formation of [Sm2 · 13], [Eu2 · 13], and [Tb2 · 13].

Relevância:

100.00% 100.00%

Publicador:

Resumo:

C21H22N6O8S2, monoclinic, P12(1)/n1 (no. 14), a = 10.1931(8) angstrom, b = 11.9627(7) angstrom, c = 20.299(2) angstrom, beta = 95.131(4)degrees, V = 2465.2 A(3), Z = 4, R-gt(F) = 0.079, wR(ref)(F-2) = 0.229, T = 100 K.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

N-Acetyl-2-azetine undergoes Lewis acid catalysed [4 + 2]-cycloaddition with imines derived from aromatic amines and gave a 1:1 mixture of exo-endo diastereoisomeric azetidine cycloadducts which reacted further with aromatic amine, to give 2,3,4-trisubsitituted tetrahydroquinolines in good to excellent yield, predominantly as one diastereoisomer.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new generation of water soluble tetrazolium salts have recently become available and in this study we compared a colorimetric assay developed using one of these salts, 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8), with a previously developed 2,3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) colorimetric assay to determine which agent is most suitable for use as a colorimetric indicator in susceptibility testing. The MICs of 6 antibiotics were determined for 33 staphylococci using both colorimetric assays and compared with those obtained using the British Society for Antimicrobial Chemotherapy reference broth microdilution method. Absolute categorical agreement between the reference and test methods ranged from 79% (cefuroxime) to 100% (vancomycin) for both assays. No minor or major errors occurred using either assay with very major errors ranging from zero (vancomycin) to seven (cefuroxime). Analysis of the distribution of differences in the log2 dilution MIC results revealed overall agreement, within the accuracy limits of the standard test (± 1 log2 dilution), using the XTT and WST-8 assays of 98% and 88%, respectively. Further studies on 31 ESBL-producing isolates were performed using the XTT method with absolute categorical agreement ranging from 87% (nitrofurantoin) to 100% (ofloxacin and meropenem). No errors were noted for either ofloxacin or meropenem with overall agreement of 91%. The data suggests that XTT is more reliable and accurate than WST-8 for use in a rapid antimicrobial susceptibility test.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Survey map of the Second Welland Canal created by the Welland Canal Company showing a portion of the Grantham Township near Port Dalhousie. Identified structures associated with the Canal include the new towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Features of the First Welland Canal are noted in red ink and include the old Lock 2, old towing path and the original bed of the Twelve Mile Creek. Local area landmarks are also identified and include streets and roads (ex. Side Line and Old Road), four unnamed bridges, and a tree stump along the old towing path. A New Road to Port Dalhousie is featured in red ink. Properties and property owners of note are: Concession 3 Lots 21, 22 and 23, Concession 4 Lots 21, 22 and 23, Jabez Johnson, Adam Gould, Peter Weaver and Samuel Wood.