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71.
S. Grégoire R. Cubberley H. Duplan J. Eilstein D. Lange N. Hewitt C. Jacques-Jamin M. Klaric H. Rothe C. Ellison O. Vaillant A. Schepky 《Journal of solution chemistry》2017,46(7):1349-1363
Aqueous solubility is one of the main physicochemical parameters used to assess skin absorption. As solvents have great impact on skin absorption, knowledge of chemical solubility in appropriate solvents is key to correlate in vitro skin penetration with in vivo outcomes. For example, acetone:olive oil, ethanol and dimethyl sulfoxide are all relevant to in vitro and in vivo assays. Solubility information is also needed to identify the optimal solvent for skin penetration assays. Therefore, we have measured the solubilities of 54 chemicals related to cosmetics and the reference controls for skin sensitization and genotoxicity, in five different solvents: water, DMSO, ethanol, acetone:olive oil (4:1), 5% ethanol in 0.1 mol·L?1 phosphate buffered saline. The solubility protocol resulted in highly reproducible values, with greatest variability for poorly soluble chemicals, especially those in 0.1 mol·L?1 PBS, which may be due to the high salt content. There was good agreement between experimental and literature values for water solubility (mean difference < twofold). A better correlation of experimental values with in silico predictions was obtained using ACD/Labs software (mean difference < fourfold, R2 = 0.64) than WSKOW from EpiSuite (mean difference < eightfold, R2 = 0.48). Chemicals with a log10P > 2 generally exhibited a poor solubility in water but a much higher solubility in acetone:olive oil, ethanol and DMSO. These five solvents include pH effects, acceptor and donor hydrogen bonding and non-polar interactions. Thus, the solubility profile across these different solvents would help to characterize the chemicals related to their cutaneous absorption with different vehicles and their toxicity assessment. 相似文献
72.
Robert Katava Sandra Kraljević Pavelić Anja Harej Tomica Hrenar Gordana Pavlović 《Structural chemistry》2017,28(3):709-721
The in situ condensation reaction of 2-hydrazinobenzothiazole with salicylaldehyde, 3,4-dihydroxybenzaldehyde, 2,4-dihydroxybenzaldehyde, 2,5-dihydroxybenzaldehyde, 2,3-dihydroxybenzaldehyde, 2-hydroxy-1-naphthaldehyde, 2-methoxy-1-naphthaldehyde, 4-methoxy-1-naphthaldehyde and 6-methoxy-2-naphthaldehyde produced 9 hydrazone Schiff bases (L1–L9, respectively) which were identified and characterized by elemental analysis, IR and NMR spectroscopy. The crystal and molecular structures of four Schiff bases (L1, L7–L9) have been determined by the single-crystal X-ray diffraction method confirming the imino form of L1 and the amino tautomeric form of L7–L9 compounds. Molecular structure analysis also confirmed that reported compounds are E-isomers relative to exo C = N imino bond. The Nhydrazino–H group of amino tautomers forms Nhydrazino–H···Nthiazolyl intermolecular hydrogen bonds shaping molecules into R 2 2 (8) rings, while imino tautomer of L1 forms C(4) infinite helical chains via Nthiazolyl–H···Nhydrazino type of intermolecular hydrogen bond. The methoxy group (L7–L9) further shaped these primary supramolecular synthons into different supramolecular arrangements via C–H···O, C–H···N and C–H···S intermolecular hydrogen bonds. The role of aryl substituents in the shaping and stabilization of supramolecular architectures of L1, L7–L9 is supported by quantum chemical calculations. Strong antiproliferative effects on tumor cells and cytotoxic effects on fibroblasts are shown for all ligands L1–L9 with exception of L6 and L7 that had no effect on fibroblast cells. 相似文献
73.
Adel S. A. Alimmari Bojan ?. Bo?i? Aleksandar D. Marinkovi? Du?an ?. Mijin Gordana S. U??umli? 《Journal of solution chemistry》2012,41(10):1825-1835
A series of 4,6-disubstituted-3-cyano-2-pyridones was synthesized and their UV?CVis absorption spectra were recorded in the region 200?C600?nm in the set of selected solvents. The effects of solvent dipolarity/polarizability and solvent?Csolute hydrogen-bonding interactions on the spectral shifts were analyzed by means of the linear solvation energy relationship concept of Kamlet and Taft. The influence of solvents as well as substituents on the 2-pyridone/2-hydroxypyridine tautomeric equilibration was evaluated. The absorption band maximum of the 2-hydroxypyridine form is found to appear at a shorter wavelength than that of the 2-pyridone form in all investigated solvents. The replacement of the methyl and phenyl groups at position 6 of the pyridone ring, by a hydroxy group, significantly changes the solvatochromic behavior of the investigated pyridones. 相似文献
74.
This work is on the synthesis and characterisation of a new phosphine stabilised palladium compound. the compound was first obtained from the rejects of cluster syntheses stored in the laboratory. Later on, it was prepared from PdCl2 and triphenyl phosphine. the compound was characterised by 31P {1H} NMR, UV/visible spectroscopy and elemental analysis. the crystal and molecular structure of Pd2(PPh3)3Cl5O was determined by X-ray analysis. the compound crystallizes in orthorhombic space group Pbca, N° 61, a = 19.009(2)Å, b=22.283(2)Å, c=23.726(2)Å, V=10050(20)Å3, Z=8 residuals R[I>2σ(I)]=0.0457 and R(all) = 0.0636, MoKα radiation, 20 °C. 相似文献
75.
Gordana Mili? Bajram Jakupi Shinji Tokonami Radmila Trajkovi? Tetsuo Ishikawa Igor ?elikovi? Predrag Uji? Olivera ?ukni? Ilia Yarmoshenko Katica Kosanovi? Feriz Adrovi? Sarat K. Sahoo Nenad Veselinovi? Zora S. ?uni? 《Radiation measurements》2010,45(1):118-121
This paper deals with the results of indoor radon and thoron concentrations and exposure doses obtained for 63 dwellings out of the 14 rural communities of Central Kosovo, North Kosovo and Prizren region. These research activities are part of overall radiological research that has systematically been carried out since 1986, particularly in Kosovo and Metohija regions. Passive radon/thoron discriminative detectors, exposed for three months, were used. The arithmetic mean concentrations of indoor radon and thoron are CRn = 429 Bq m?3 CTn = 85 Bq m?3. 相似文献
76.
Bukonjić Andriana M. Tomović Dušan Lj. Stanković Ana S. Jevtić Verica V. Ratković Zoran R. Bogojeski Jovana V. Milovanović Jelena Z. Đorđević Dragana B. Arsenijević Aleksandar N. Milovanović Marija Z. Potočňák Ivan Trifunović Srećko R. Radić Gordana P. 《Transition Metal Chemistry》2019,44(1):65-76
Transition Metal Chemistry - Two copper(II) complexes with ligands derived from β-amino acids, 2-(1-aminocyclohexyl)acetic acid L1 and 2-(1-amino-4-(tert-butyl)cyclohexyl)acetic acid L2, were... 相似文献
77.
78.
Gordana Klaric Felic Feras Al-Dirini Faruque M. Hossain Thanh Cong Nguyen Efstratios Skafidas 《Applied Physics A: Materials Science & Processing》2014,115(2):491-493
Properties of surface plasmon polaritons can be exploited for the miniaturisation of photonic circuits below the optical wavelength scale. Smaller and more sensitive photodetectors can be made by using sub-wavelength semiconductor elements such as germanium or silicon nanowires in combination with nanometer-scale antennas. The proposed nanowire photodetector enables on-chip optical sensing applications with increased sensitivity and reduced size. 相似文献
79.
New substituted anilides of the heterocyclic series 2, 4, 5, 6, 7 together with the earlier described compounds 1 and 3 (Jarak I et al. (2005) J Med Chem 48:2346), were synthesized from the corresponding heterocyclic carbonyl chlorides, methoxycarbonyl-
and cyano-substituted anilines. Compounds 2 and 7 were prepared by methylation with methyl-iodide on the amide and the pyridine nitrogen. The Pinner reaction was used in the
preparations of amidino-substituted compounds. It seems that all the prepared compounds could be biologically interesting,
especially amidino-substituted anilides prepared in the form of water-soluble hydrochlorides or hydroiodides.
Molecular and crystal structures of the three compounds, namely, 4′-methoxycarbonyl-N-phenyl-3-chlorobenzo[b]thiophene-2-carboxamide (1), N-(4′-amidinophenyl)-3-chlorobenzo[b]thiophene-2-carboxamide hydrochloride monohydrate (4) and 1-methyl-N-(4-amidinophenyl)-3-pyridine carboxamide iodide hydroiodide (7) have been determined by X-ray single-crystal diffractometry in the solid state. Compounds 1, 4 and 7 are not planar and the amide group (C=O in relation to NH group) is in trans position in all three compounds. The 3-chlorobenzo[b]thiophene moiety in 1 and 4 is oriented with the chloro substituent in cis position in relation to amide NH group. The conformational characteristics of the compounds result from the introduction
of different substituents or solvent molecules (water molecule in 4), which leads to various intermolecular hydrogen bonds formation (N–H⋯O, N–H⋯Cl, O–H⋯Cl−, N–H⋯I−) in 1, 4 and 7. Hydrogen bond formation could be responsible for the potential biological activity of the compounds. 相似文献
80.
Ana Dunja Mance Branko Borovi
ka KreImir Jakop
i Gordana Pavlovi Ivan Leban 《Journal of heterocyclic chemistry》2002,39(2):277-285
Methoxy or nitro group present in the furan ring of tertiary alkenylfurfurylamine changes the expected results of both, the intramolecular [4+2]cycloaddition and the acid catalyzed ring‐opening reaction of the derived oxatricycloadduct. With a 5‐methoxy group, in addition to the expected 5‐methoxyisoindoline 3 , the corresponding hydroxy derivative 5 was obtained. On the other hand a 5‐nitro group changes the outcome of the reaction even more profoundly. Instead of the expected 5‐nitroisoindoline 12 , 5‐nitro‐substituted epoxy‐isoindoline 6 submitted to ring‐opening reaction with the mixture of hydrobromic and acetic acid, yielded the mixture of bromo‐substituted epoxy compounds 7,8, 9 and/or bromo‐substituted isoindolines 10 and 11 . 相似文献