Vol 80, No 5 - Abstracts

JSCS Vol 80, No 5

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Whole issue - PDF 3,286 kB

J. Serb. Chem. Soc. 80 (5) 595–604 (2015)

UDC 547.594+542.9+547.7:546.561’13+546.171:544.4; JSCS–4740; doi: 10.2298/JSC141028011J; Original scientific paper

Double catalytic effect of (PhNH₃)₂CuCl₄ in a novel, highly efficient synthesis of 2-oxo- and thioxo-1,2,3,4-tetrahydropyrimidines

NENAD JANKOVIĆ, ZORICA BUGARČIĆ and SVETLANA MARKOVIĆ

University of Kragujevac, Faculty of Science, Department of Chemistry, Radoja Domanovića 12, 34 000 Kragujevac, Serbia

(Received 28 October 2014, revised 13 February, accepted 13 February 2015)

An innovative route for the construction of 2-oxo- and thioxo-1,2,3,4-tetrahydropyrimidines was delineated through a multicomponent reaction under Biginelli conditions, starting from different aromatic aldehydes, b-keto esters and urea or thiourea. The proper choice of the copper complex (PhNH3)2CuCl4, as a novel homogeneous catalyst, enabled a facile, efficient, and inexpensive reaction under mild experimental conditions. Moreover, the first application of this complex salts in organic synthesis ever is presented. The obtained products were of high purity, and could be easily isolated from the reaction mixture in good to excellent yields. Moreover, compared to the classical Biginelli reaction conditions, the present method has the advantages of higher yields and experimental and work-up simplicity. To illustrate the joint catalytic action of the Cu2+ and phenylammonium ions, two key steps of Biginelli reaction were examined using the M06 functional.

Keywords: aldehydes; multicomponent reactions; heterocycles; homogeneous catalysis; density functional calculations.

Full Article - PDF 254 kB Supplementary Material PDF 836 kB Available OnLine: 15. 02. 2015. Cited by

J. Serb. Chem. Soc. 80 (5) 605–612 (2015)

UDC 547.595.4+547.269.3+546.41’46’47:547.466.1+542.913:66.094.522:615.277; JSCS–4741; doi: 10.2298/JSC131128032F; Original scientific paper

Aminopeptidase N inhibition could be involved in the anti-angiogenic effect of dobesilates

OLDŘICH FARSA, ŠÁRKA SEDLÁKOVÁ, JANA PODLIPNÁ* AND JAROSLAV MAXA*

Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 61242 Brno, Czech Republic

*Official Laboratory for Medicines Control, Institute for State Control of Veterinary Biologicals and Medicines, Hudcova 56a, 62100 Brno-Medlánky, Czech Republic

(Received 28 November 2013, revised and accepted 31 March 2014)

Calcium, magnesium and zinc 2,5-dihydroxybenzenesulfonates (dobesilates) were synthesized by sulfonation of hydroquinone with sulfuric acid under mild conditions. To form the salts, neutralization with calcium carbonate followed by cation exchange by means of magnesium or zinc sulfates was performed. The dobesilates were characterized by standard spectral methods and by AAS for metal content and then tested for inhibitory activity against aminopeptidase N. The calcium and magnesium 2,5-dihydroxybenzenesulfonates exhibited rather weak inhibitory activity to aminopeptidase N, as demonstrated by the IC50 values of 978.0 and 832.1 mmol L-1, respectively, while zinc 2,5-dihydroxybenzenesulfonate reached a more significant inhibitory activity characterized by an IC50 value of 77.4 mmol L-1. The results of the inhibition activity suggest that the inhibition of aminopeptidase N could play a role in the anti-angiogenic activity of 2,5-dihydroxybenzenesulfonates.

Keywords: 2,5-dihydroxybenzenesulfonic acid salts; effect on CD13 activity; neovascularization; carcinogenesis; vasculopathies.

Full Article - PDF 134 kB Supplementary Material PDF 64 kB Available OnLine: 01. 04. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 613–625 (2015)

UDC 547.964.2+546.33’226:54.121:536.7+544.4:541.121; JSCS–4742; doi: 10.2298/JSC140901007R; Original scientific paper

Evidence of b-sheet structure induced kinetic stability of papain upon thermal and sodium dodecyl sulfate denaturation

BRANKICA RAŠKOVIĆ, NIKOLINA BABIĆ, JELENA KORAĆ and NATALIJA POLOVIĆ

Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 12–16, 11158 Belgrade, Serbia

(Received 1 September, revised 11 December, accepted 16 December 2014)

Papain is a protease that consists of α-helical and β-sheet domains that unfold almost independently. Both, considerable thermal stability and sodium dodecyl sulfate (SDS) resistance of papain have been shown. However, the ability of each domain to unfold upon thermal and SDS denaturation has never been studied. This work shows that fruit papain has slightly higher resistance to thermal inactivation when compared to that of stem papain with a rather high activation energy (Ea) of 223±16 kJ mol-1 and a Tm50 value of 79±2 °C. The SDS resistance of fruit papain was estimated by SDS–PAGE analysis and activity staining. It was noted that, in the presence of SDS the protein remained active, unless heat energy was applied in order to unfold papain. Furthermore, it was proven via Fourier transform infrared spectroscopy (FT--IR) that an α-helical domain of fruit papain is more prone to unfolding at elevated temperatures and in the presence of SDS then a β-sheet rich domain. Thermal denaturation of papain without detergent present led to accelerated formation of aggregation specific intermolecular β-sheets as compared to native protein. The presented results are of both fundamental and practical importance.

Keywords: thermal inactivation; SDS resistance; secondary structure; FT-IR spectroscopy.

Full Article - PDF 427 kB Available OnLine: 29. 01. 2015. Cited by

J. Serb. Chem. Soc. 80 (5) 627–637 (2015)

UDC 547.313.3+547.295.91+547.828:541.515:620.266.1:616.36:616.853; JSCS–4743; doi: 10.2298/JSC140812123C; Original scientific paper

Edaravone, a free radical scavenger, protects liver against valproic acid induced toxicity

NEZIHA HACIHASANOGLU CAKMAK and REFIYE YANARDAG

Department of Chemistry Faculty of Engineering, Istanbul University, 34320, Avcilar-Istanbul, Turkey

(Received 12 August, revised 10 December, accepted 22 December 2014)

Valproic acid (VPA) is a well-established anticonvulsant drug that has been increasingly used in the treatment of many forms of generalized epilepsy. Edaravone (EDA, 3-methyl-1-phenyl-2-pyrazolin-5-one) is a potent free radical scavenger. In this study, the aim was to investigate the effects of EDA on VPA-induced hepatic damage. Male Sprague Dawley rats were divided into four groups. Group I was control animals. Group II was control rats given valproic acid (500 mg kg-1 day-1) for seven days. Group III was given only EDA (30 mg kg-1 day-1) for seven days. Group IV was given VPA+EDA (at the same dose and in the same time). EDA and VPA were administered intraperitoneally. On the 8th day of the experiment, blood samples and liver tissue were taken. Serum aspartate and alanine aminotransferase, alkaline phosphatase and bilirubin levels, liver myeloperoxidase, xanthine oxidase, adenosine deaminase, Na+/K+ATPase, sorbitol dehydrogenase, glutamate dehydrogenase, DT-diaphorase, arginase and thromboplastic activities, lipid peroxidation, protein carbonyl levels were increased whereas paraoxonase and biotinidase activities and glutathione levels were decreased in the VPA group. Application of EDA with VPA protected against VPA-induced effects. These results demonstrated that administration of EDA is potentially beneficial to reduce hepatic damage in VPA-induced hepatotoxicity, probably by decreasing oxidative stress.

Keywords: edaravone; hepatotoxicity; hepatic enzymes; rat; valproic acid; free radicals.

Full Article - PDF 146 kB Available OnLine: 29. 12. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 639–649 (2015)

UDC 547.233’821+546.96+547.544:57–188:615.281; JSCS–4744; doi: 10.2298/JSC140704086M; Original scientific paper

A study on tailor made ruthenium sulphoxide complexes: Synthesis, characterization and application

RIPUL MEHROTRA, SATYENDRA N. SHUKLA and PRATIKSHA GAUR

Coordination Chemistry Research Lab, Department of Chemistry, Govt. Model Science College Jabalpur (MP) 482001, India

(Received 4 July, revised 11 August, accepted 31 August 2014)

In this study, a dinucleating spacer incorporating two 2-aminopyridine units was used to prepare seven novel dinuclear compounds. These molecules were characterized by elemental analyses, conductivity measurements, magnetic susceptibility, FT-IR, FAB-Mass, electronic, 1H-NMR and 13C{1H}-NMR spectral studies. The complex [{trans,mer-RuCl2(DMSO)3}2(μ-5,5′-methylenebis(2-aminopyridine))]·2DMSO (2) was also characterized through 1H-1H COSY NMR. There are mainly three different formulations, [{cis,fac-RuCl2(SO)3}2(µ-MBAP)]·2SO; [{trans,mer-RuCl2(SO)3}2(µ-MBAP)]·2SO and [{trans-RuCl4(SO)}2(µ-MBAP)]2- [X]2+; where SO = DMSO / TMSO; MBAP = 5,5′-methylenebis(2-pyridinamine) and [X]+ = [(DMSO)2H]+, Na+ or [(TMSO)H]+. The coordination was found through cyclic nitrogen of the pyridine ring in an octahedral environment for both metal centres. The chemical behaviour of [{cis,fac-RuCl2(DMSO)3}2(μ-5,5′-methylenebis(2-pyridinamine))]·2DMSO (1) and (2) in aqueous solution with respect to time was observed by conductivity measurements and UV–Vis spectrophotometry. All complexes were found to possess prominent antibacterial activity against Escherichia coli in comparison to chloramphenicol and gatifloxacin.

Keywords: 2-aminopyridine; antibacterial; dinuclear; ruthenium; spacer; sulphoxide.

Full Article - PDF 209 kB Supplementary Material PDF 127 kB Available OnLine: 04. 06. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 651–658 (2015)

UDC 547–311+546.161–32+544.351–145.82:547.312; JSCS–4745, doi: 10.2298/JSC140923002D; Original scientific paper

Solvent effect on ternary complexes formed by oxirane and hydrofluoric acid

BOAZ G. OLIVEIRA

Institute of Environmental Sciences and Sustainable Development (ICADS), Federal University of Bahia, 47801-100, Barreiras – BA, Brazil

(Received 23 September 2014, revised 7 January, accepted 8 January 2015)

The solvent effect on derivatives of the C2H4O…HF…HF ternary complex was investigated through the PCM approach and AGOA calculations at the B3LYP/6-311++G(d,p) level of theory. Continuous analysis was useful to verify the profiles of the hydrogen bond distances in the complex, specifically the O…H, F…H, and F…Hβ contacts. From the viewpoint of AGOA, the configurations of the water molecules, followed by measurement of the discrete hydration energies, were unveiled. Through single point energy calculations, the hydration energies were determined via the supermolecule approach, and the values were corrected by the counterpoise correction of the basis sets superposition error (BSSE). In line with this, the analysis of the molecular electrostatic potential (MEP) revealed positive and negative regions, which represent the interaction sites for the water molecules regarding the oxygen and hydrogen, respectively. In an overview, the acid-catalyzed oxirane ring-opening reaction has distinct interpretations both in vacuum and in aqueous medium depending on whether the most appropriate structure of the C2H4O…HF…HF trimolecular complex is taken into consideration.

Keywords: hydrogen bonds; oxirane; hydrofluoric acid; PCM; AGOA.

Full Article - PDF 157 kB Supplementary Material PDF 172 kB Available OnLine: 11. 01. 2015. Cited by

J. Serb. Chem. Soc. 80 (5) 659–671 (2015)

UDC 547.53+532.11+54–134+533.75:519.245; JSCS–4746; doi:10.2298/JSC140416051O; Original scientific paper

Quantitative relationships for the prediction of the vapor pressure of some hydrocarbons from the van der Waals molecular surface

TUDOR OLARIU, VICENŢIU VLAIA, CIPRIAN CIUBOTARIU*, DAN DRAGOŞ, DAN CIUBOTARIU and MIRCEA MRACEC**

Department of Organic Chemistry, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy, P-ta Eftimie Murgu No. 2, 300041, Timisoara, Romania

*Department of Computer Sciences, University “Politehnica”, P-ta Victoriei No. 2, 300006, Timisoara, Romania

**Molecular Forecast Research Center, Prof. Dr. Aurel Păunescu-Podeanu str. 125, A 4, RO-300588 Timişoara, Romania

(Received 16 April, accepted 17 May 2014)

A quantitative structure–property relationship (QSPR) modeling of vapor pressure at 298.15 K, expressed as log (VP / Pa) was performed for a series of 84 hydrocarbons (63 alkanes and 21 cycloalkanes) using the van der Waals (vdW) surface area, SW / Å², calculated by the Monte Carlo method, as the molecular descriptor. The QSPR model developed from the subset of 63 alkanes (C1–C16), deemed as the training set, was successfully used for the prediction of the log (VP / Pa) values of the 21 cycloalkanes, which was the external prediction (test) subset. A QSPR model was also developed for a series composed of all 84 hydrocarbons. Both QSPR models were statistically tested for their ability to fit the data and for prediction. The results showed that the vdW molecular surface used as molecular descriptor (MD) explains the variance of the majority of the log (VP / Pa) values in this series of 84 hydrocarbons. This MD describes very well the intermolecular forces that hold neutral molecules together. The clear physical meaning of the molecular surface values, SW / Å², could explain the success of the QSPR models obtained with a single structural molecular descriptor.

Keywords: MD – molecular descriptor; van der Waals molecular surface; Monte Carlo method; QSPR.

Full Article - PDF 210 kB Supplementary Material PDF 71 kB Available OnLine: 22. 05. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 673–683 (2015)

UDC 532.783+547.655.1+541.57:547.26’11; JSCS–4747; doi: 10.2298/JSC140725126S; Original scientific paper

Unsymmetrical banana-shaped liquid crystalline compounds derived from 2,7-dihydroxynaphthalene

AUREL SIMION, COSMIN-CONSTANTIN HUZUM, IRINA CARLESCU, GABRIELA LISA, MIHAELA BALAN* and DAN SCUTARU

1Faculty of Chemical Engineering and Environmental Protection, Gheorghe Asachi Technical University of Iasi, 71 D. Mangeron St., 700050 – Iaşi, Romania

*Petru Poni Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda 41A, 700487-Iasi, Romania

(Received 25 July, revised 16 December, accepted 23 December 2014)

The synthesis and characterization of new asymmetric bent-core compounds derived from 2,7-dihydroxynaphthalene with various connecting groups between the aromatic rings and alkyloxy terminal substituents at the end of the long arm are presented. Some 1,4-disubstituted phenylene rings with an azo or ester linkage between them have been used as calamitic pro-mesogen units. The synthetic strategies to obtain the final esteric derivatives involved the esterification of 7-(benzyloxy)naphthalen-2-ol with 4-((4-(alkyloxy)phenyl)azo)benzoyl chlorides or with 4-((4-(alkyloxy)benzoyl)oxy)benzoic acids in the presence of dicyclohexylcarbodiimide (DCC) and 4-(dimethylamino)pyridine (DMAP). The mesomorphic properties were assigned by optical polarizing microscopy and differential scanning calorimetry. All the compounds showed mesomorphic properties of the enantiotropic or monotropic type, the liquid crystalline behavior depending on the linking group between the phenylene rings. Thermogravimetric studies evidenced that all compounds were stable in the range of the existence of mesophases.

Keywords: liquid crystals; asymmetric bent-core; 2,7-naphthalenediol.

Full Article - PDF 332 kB Supplementary Material PDF 68 kB Available OnLine: 29. 12. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 685–694 (2015)

UDC 546.881–31+541.135.5+544.6.076.2+546.34:621.354.32; JSCS–4748; doi: 10.2298/JSC140922128M; Original scientific paper

High performance of solvothermally prepared VO₂(B) as an anode for aqueous rechargeable lithium batteries

SANJA MILOŠEVIĆ, IVANA STOJKOVIĆ*, MIODRAG MITRIĆ** and NIKOLA CVJETIĆANIN*

The Vinča Institute, Department of Materials Science, University of Belgrade, P. O. Box 522, 11001 Belgrade, Serbia

*Faculty of Physical Chemistry, University of Belgrade, 11158 Belgrade, Serbia

**The Vinča Institute, Laboratory for Theoretical and Condensed Matter Physics, University of Belgrade, P. O. Box 522, 11001 Belgrade, Serbia

(Received 22 September, revised 3 December, accepted 25 December 2014)

The VO2(B) was synthesized via a simple solvothermal route at 160 °C in ethanol. The initial discharge capacity of the VO2(B) anode, in saturated aqueous solution of LiNO3, was 177 mAh g-1 at a current rate of 50 mA g-1. After 50 cycles, the capacity fade was 4 %, but from 20th–50th cycle, no capacity drop was observed. The VO2(B) showed very good cyclability at a current rate of even 1000 mA g-1 with initial discharge capacity of 92 mAh g-1. The excellent electrochemical performance of VO2(B) was attributed to the stability of micro–nano structures to a repeated intercalation/deintercalation process, very good electronic conductivity as well as the very low charge transfer resistance in an aqueous electrolyte.

Keywords: aqueous rechargeable lithium batteries; anode materials; discharge capacity; electrochemical impedance spectroscopy; electric conductivity.

Full Article - PDF 258 kB Supplementary Material PDF 128 kB Available OnLine: 29. 12. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 695–704 (2015)

UDC 547.262+66.021.2.063.8:66.09.001.57:544.032.4; JSCS–4749; doi: 10.2298/JSC140617095H; Original scientific paper

Solubility of atenolol in ethanol + water mixtures at various temperatures

SAMIN HAMIDI and ABOLGHASEM JOUYBAN*

Liver and Gastrointestinal Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran

*Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz 51664, Iran and Pharmaceutical Engineering Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran, P. O. Box 11155/4563, Tehran, Iran

(Received 17 June, revised 17 September, accepted 18 September 2014)

The experimental solubility of atenolol in ethanol + water mixtures at different temperatures (298.2, 303.2, 308.2 and 313.2 K) was reported. The solubility was calculated using five numerical methods. First, the Jouyban–Acree model (method I), its combination with the van't Hoff equation (method II) and the extended version of the Jouyban–Acree model with Abraham parameters (method III) were employed. The minimum number of data points (N) were used to train the Jouyban–Acree model (N = 11) and its combination with the van’t Hoff equation (N = 22), then the obtained parameters of the models were used to calculate the solubilites at other temperatures (methods IV and V). The accuracies of the calculated solubilites were evaluated by computing mean percentage deviation (MPD). The obtained MPDs (±standard deviation) for methods I–V were 5.6±7.1, 5.1±4.6, 34.1±28.0, 10.0±9.6 and 6.6±4.8 %, respectively.

Keywords: mixed solvent; simulation; Jouyban–Acree model.

Full Article - PDF 181 kB Available OnLine: 22. 09. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 705–715 (2015)

UDC 546.821–31+546.57:678.746:678.026.2:544.032.6.004.4:615.281–188; JSCS–4750; doi: 10.2298/JSC141104125M; Original scientific paper

Antibacterial and UV protective properties of polyamide fabric impregnated with TiO₂/Ag nanoparticles

MILICA MILOŠEVIĆ, ANA KRKOBABIĆ*, MARIJA RADOIČIĆ, ZORAN ŠAPONJIĆ*, VESNA LAZIĆ**, MILOVAN STOILJKOVIĆ and MAJA RADETIĆ*

“Vinča” Institute of Nuclear Sciences, University of Belgrade, P. O. Box 522, 11001 Belgrade, Serbia

*Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade, Serbia

*Innovation Center of the Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade, Serbia

(Received 4 November, revised 15 December, accepted 19 December 2014)

The possibility of in situ photoreduction of Ag+ using colloidal TiO2 nanoparticles deposited on the surface of polyamide fabric in the presence of the amino acid alanine and methanol is discussed. The presence of TiO2/Ag nanoparticles on the polyamide fabric was confirmed by FESEM and ICP analyses. The antibacterial activity of the fabric was tested against the Gram-negative bacterium Escherichia coli and the Gram-positive bacterium Staphylococcus aureus. The TiO2/Ag nanoparticles fabricated on the surface of the polyamide fabric provided maximum bacterial reduction and thus, excellent antibacterial activity. In spite of silver leaching from the fabric during washing, the impregnated polyamide fabric preserved the maximum reduction of E. coli colonies. The antibacterial activity against S. aureus was slightly decreased after ten washing cycles, but still the antibacterial activity could be considered as satisfactory. In addition, the presence of TiO2/Ag nanoparticles ensured better UV protection efficiency, which belonged to the UV protection category very good.

Keywords: TiO2/Ag nanoparticles; polyamide; photoreduction; antibacterial activity; UV protection.

Full Article - PDF 290 kB Available OnLine: 29. 12. 2014. Cited by

J. Serb. Chem. Soc. 80 (5) 717–729 (2015)

UDC 547.992+544.478+546.3–31:549.67:547.56:665.61–57+66.092–977; JSCS–4751; doi: 10.2298/JSC310714109M; Original scientific paper

Modification of natural clinoptilolite and ZSM-5 with different oxides and a study of the obtained products in lignin pyrolysis

JELENA A. MILOVANOVIĆ, RUTH ELISABETH STENSRØD*, ELISABETH M. MYHRVOLD*, ROMAN TSCHENTSCHER*, MICHAEL STÖCKER*, SLAVICA S. LAZAREVIĆ** and NEVENKA Z. RAJIĆ**

Innovation Centre of the Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia

*SINTEF, Forskningsveien 1, 0314 Oslo, Norway

**Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia

(Received 31 July, revised 17 October, accepted 6 November 2014)

In this work, different metal oxides (MO) supported on two types of zeolites: 1) natural clinoptilolite (NZ) and 2) synthetic zeolite, ZSM-5 were prepared and tested as catalysts in the fast pyrolysis of hardwood lignin. NZ was modified with the CaO and MgO by a simple two steps procedure consisting of an ion exchange reaction and subsequent calcination at 773 K. The synthetic ZSM-5 was modified with several MO species (Ni, Cu, Ca, Mg) by wet impregnation and calcination at 873 K. The prepared catalysts were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDS), and measurement of their specific surface area (BET method). Acid sites were characterized and quantified by pyridine (py) absorption using Fourier transform infrared spectroscopy (FTIR). The catalysts exhibit catalytic activity depending on modification, reaction temperature and of the MO contents. The highest yield of useful phenol in bio-oil was obtained with NiO/ZSM-5 (34.8 wt. %) which exhibits the highest specific surface area and the highest concentration of Brönsted and Lewis acid sites. The studied catalysts did not increase significantly the content of polycyclic aromatic hydrocarbons (PAHs) and ‛heavy’ compounds (phenols with Mr > 164 g mol-1) compared to non-catalytic experiment.

Keywords: lignin; catalysts; natural zeolite; ZSM-5; bio-oil; phenol.

Full Article - PDF 217 kB Supplementary Material PDF 170 kB Available OnLine: 09. 04. 2014. Cited by

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