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1.
Vytautas Getautis Albina Stanisauskaite Tadas Malinauskas Jolanta Stumbraite Valentas Gaidelis Vygintas Jankauskas 《Monatshefte für Chemie / Chemical Monthly》2006,23(12):1401-1409
Hydrazones containing 1-phenyl-1,2,3,4-tetrahydroquinoline units were synthesized starting from diphenylamine. These compounds
were found to constitute novel hole transporting materials and were characterized by the time of flight method. The hole drift
mobility in these compounds exceeds 10−6 cm2 V−1 s−1 at an electric field of 106 V cm−1. 相似文献
2.
Summary. Phenoxyacetic acid distribution in two-phase systems n-aliphatic hydrocarbon (C5–C8) – water and its dimerization in organic phase were investigated. The values of distribution coefficient (D
HR), distribution constant (K
D), and dimerization constant (K
dim) of acid were obtained. The empirical correlations of these quantities with Hildebrand solubility parameter of organic solvents were established. The influence of pH of the aqueous phase as well as the polarity of the applied organic solvents on phenoxyacetic acid physical chemistry in
the two-phase systems was described. 相似文献
3.
A vinyl bis-sulfone Michael type approach towards heteroatom vinylation was applied on nitrogen derivatives. Cyclic thionocarbamates--mainly 1,3-oxazolidine-2-thiones--were converted into their N-vinyl counterparts; the procedure proved particularly efficient in the case of carbohydrate-derived complex structures. 相似文献
4.
Jolanta Obniska Krzysztof Kaminski Agnieszka Dzierzawska-Majewska 《Journal of fluorine chemistry》2006,127(3):417-425
A series of N-phenyl- and N-benzyl-2-azaspiro[4.4]nonane- and [4.5]decane-1,3-diones containing a fluoro or trifluoromethyl substituents at the aryl ring was synthesized and tested for their anticonvulsant activity in the maximal electroshock (MES) and subcutaneous metrazole (sc.Met) tests. Among them, the most active were N-benzyl derivatives with fluoro and trifluoromethyl substituents especially at position-2 of the aryl moiety. The introduction of the phenyl ring at the imide nitrogen atom resulted in less active compounds. The results obtained showed that incorporation of fluoro or trifluoromethyl substituents increased the anticonvulsant activity in comparison to respective chloro, methoxy or methyl analogues. Crystallographically obtained conformation for one active and two inactive derivatives with trifluoromethyl substituents at position-2 or -3 of phenyl ring were initially used for molecular electrostatic potentials (MEP) calculation. The MEP distribution at carbonyl oxygen atoms was different for active and inactive molecules. 相似文献
5.
Jolanta Olkowska‐Oetzel Dieter Fenske Petra Scheer Andreas Eichhfer 《无机化学与普通化学杂志》2003,629(3):415-420
Syntheses and Thermal Properties of Cluster Molecules, formed from Groups 11‐13‐16 Elements In the presence of PPh3, CuX (X = Cl, CH3COO) or AgOC(O)C6H5 and GaCl3 react in THF with S(SiMe3)2 or Se(SiMe3)2 to yield [Cu6Ga8Cl4S13(PPh3)6] ( 1 ), [Cu6Ga8Cl4Se13(PPh3)6] ( 2 ), [Ag6Ga8Cl4S13(PPh3)6] ( 4 ) and [Ag6Ga8Cl4Se13(PPh3)6] ( 5 ). The use of PnPr2Ph instead of PPh3 and subsequent layering with n‐hexane leads to the formation of the cluster [Cu6Ga8Cl4Se13(PnPr2Ph)12] ( 3a , 3b ). Reaction of CuCl, GaCl3 and PnPr3 with Se(SiMe3)2 in THF results in the crystallisation of the ionic cluster (HPnPr3)2[Cu2Ga4Cl4Se6(PnPr3)4] ( 6 ). The structures of 1 — 6 were determined by X‐ray single crystal structure analysis. Thermogravimetric measurements of the cluster molecules and powder diffraction patterns of the remaining powders reveal the potential use of them as single source precursor compounds for the synthesis of the related ternary solid state materials. 相似文献
6.
Andrzej Olczak Marek L. Gwka Jolanta Goka Magorzata Szczesio Joanna Bojarska Krystyna Kozowska Henryk Foks Czesawa Orlewska 《Journal of Molecular Structure》2007,830(1-3):171-175
Crystal structures of two title compounds and several their relatives known earlier reveal conservative and characteristic features, which may be related to their tuberculostatic activity. The molecules are predominantly planar due to conjugation through five successive bonds in the zwitterionic fragment S−–C(sp2)–N–NH+–C(sp2)–NH2 and intramolecular hydrogen bonds, which prevent rotation of the adjacent pyrazine (or pyridine) ring. It has been suggested that in spatial sense such planar molecules resemble acridines intercalating with nucleic acids and that similar process may be responsible for tuberculostatic activity of the title pyrazine-2-carboxamide-N′-carbonothioyl-hydrazones. 相似文献
7.
A liquid ion-exchange electrode containing a complex of mercury(II) with N-(O,O-diisopropylthiophosphoryl)thiobenzamide in carbon tetrachloride is described. The electrode shows excellent sensitivity and good selectivity. The slope of the calibration graph is 29.0 mV/pHg2+ in the pHg2+ in the pHg2+ range 2–15.2 in mercury(II) ion buffers. The electrode can be used for determination of 5 × 10?5–10?2 M Hg(II) in the presence of 10?2 M Cu(II), Ni(II), Co(II), Zn(II), Pb(II), Cd(II), Mn(II), Fe(III), Cr(III), Bi(III) or Al(III) ions and in the presence of 10?3 M Ag(I) ions. It can bealso used for end-point detection in titrations with EDTA of 10?3–10?4 M mercury(II) at pH 2. 相似文献
8.
Marcin Marczak Lidia Wolska Wojciech Chrzanowski Jacek Namieśnik 《Mikrochimica acta》2006,155(3-4):331-348
Volatile organic compounds (VOCs), due to their toxicity and persistence in the environment, are particularly important pollutants.
Some of these compounds are mutagens, teratogens or carcinogens, while others are responsible for the degradation of organoleptic
parameters such as taste and odour of water. This review focuses on a number of key procedural steps in the analysis of volatile
organic compounds (VOCs) in water samples. A wide spectrum of techniques for the isolation and preconcentration of the aforementioned
pollutants for trace organic analysis by gas chromatography are presented and discussed. The advantages and disadvantages
of these techniques are discussed and novel developments are also taken into consideration. 相似文献
9.
Wojciech Dmowski Jolanta Ignatowska Krystyna Piasecka-Maciejewska 《Journal of fluorine chemistry》2004,125(7):1147-1151
Sodium dithionite effectively promotes the addition of 1-bromo-1-chloro-2,2,2-trifluoroethane to the exocyclic double bond of β-pinene. The reaction proceeded in an MeCN/H2O system to give almost quantitatively a 1:1 mixture of diastereoisomers of 4-(2-bromoisopropyl)-1-(2-chloro-3,3,3-trifluoropropyl)-cyclohexene (1). Dehydrobromination of 1 with pyridine gave a mixture of regioisomeric dienes 2 and 3, while treatment with DBU at elevated temperature resulted in total dehydrohalogenation to give trienes 4 and 5. Reduction of 1 with Bu3SnH gave 1-(2-chloro-3,3,3-trifluoropropyl)-4-(isopropyl)cyclohexene (6) which on dehydrochlorination with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) afforded conjugated diene, 4-isopropyl-1-(trans-3,3,3-trifluoropropenyl)-cyclohexene (7), with 50% overall yield. All the transformations proceeded with the retention of configuration at the carbon atom C-4 and the final compound 7 exhibited high optical activity. 相似文献
10.
Dyguda E Grembecka J Sokalski WA Leszczyński J 《Journal of the American Chemical Society》2005,127(6):1658-1659
Interaction energies of phenylalanine ammonia-lyase (PAL) active site residues with a series of PAL inhibitors have been partitioned into electrostatic, exchange, delocalization, and correlation components and compared with analogous results obtained previously for leucine aminopeptidase (LAP). In the latter metalloenzyme, either of the two charged residues controls entirely relative inhibitor binding energies, while at least four residues are required to determine ligand relative stabilization in neutral PAL. Significant correlation with experimental inhibitory activity was found between the stabilization energy at gradually decreasing levels of theory (MP2, SCF) down to the first-order Heitler-London term. Contrary to the LAP case, where the electrostatic term was sufficient to reproduce experimentally observed trends, in the case of PAL, exchange repulsion effects also have to be considered. Computational protocol presented herein constitutes a promising way to incorporate the first principle calculation's accuracy into the process of rational binding affinity prediction, revealing the physical nature of the interactions, where successive approximations can be introduced in a systematic and justifiable manner. 相似文献