J. Serb. Chem. Soc. 75 (11) 1463–1471 (2010)
UDC 547.79+547.286.2:547.496.3–304.2:542.913; JSCS–4068; doi: 10.2298/JSC091221122C; Original scientific paper

Synthesis and characterization of some 1,2,4-triazole-3-thiones obtained from intrAMolecular cyclization of new 1-(4-(4-X-phe-nylsulfonyl)benzoyl)-4-(4-iodophenyl)-3-thiosemicarbazides
OLGA D. CRETU, STEFANIA F. BARBUCEANU*, GABRIEL SARAMET** and CONSTANTIN DRAGHICI***

University of Medicine and Pharmacy “Carol Davila”, Faculty of Pharmacy, Pharmaceutical Botany Department, Traian Vuia Street 6, 020956, Bucharest, Romania

*University of Medicine and Pharmacy “Carol Davila”, Faculty of Pharmacy, Organic Chemistry Department, Traian Vuia Street 6, 020956, Bucharest, Romania

**Pharmaceutical Techniques and Drug Industry Department, Faculty of Pharmacy, Traian Vuia Street 6, 020956 Bucharest, Romania

***The Organic Chemistry Centre “Costin. D. Neniţescu”, Romanian Academy, Splaiul Independenţei 202B, 060023, Bucharest, Romania

(Received 21 December 2009, revised 12 July 2010)

This paper presents new heterocyclic compounds from the class of 1,2,4-triazole-3-thione which were obtained by intrAMolecular cyclization, in basic media of some acylthiosemicarbazides containing diphenyl sulfone moieties. The new 1-(4-(4-X-phenylsulfonyl)benzoyl)-4-(4-iodophenyl)-3-thiosemicarbazides (7a–c) were obtained by the reaction of 4-(4-X-phenylsulfonyl)¬benzoic acid hydrazides (6a–c) (X = H, Cl or Br) with 4-iodophenylisothiocyanate. The cyclization of the acylthiosemicarbazides 7a–c in the presence of an 8 % NaOH solution resulted in the formation of the new 5-(4-(4-X-phenylsulfonyl)phenyl)-4-(4-iodophenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiones (8a–c). The structures of the newly synthesized compounds were elucidated by spectral methods (IR, UV–Vis, ¹H-NMR, ¹³C-NMR and MS spectroscopy) and elemental analysis.

Keywords: 1-acylthiosemicarbazide; intrAMolecular cyclization; 1,2,4-triazole-3-thione.

J. Serb. Chem. Soc. 75 (11) 1473–1479 (2010)
UDC 547.239–304.2+66.095.252.091.7: 547.594.3; JSCS–4069; doi: 10.2298/JSC090824119D; Original scientific paper

Synthesis of nitrogen-containing dispiroheterocycles using nitrilimines (II)

HANY M. DALLOUL and AHMED S. ABU SAMAHA*

Chemistry Department, Faculty of Science, Al-Aqsa University of Gaza, P.O. Box 4051, 76888 Gaza, Palestine

*Biology Department, Faculty of Science, Al-Aqsa University of Gaza, P.O. Box 4051, 76888 Gaza, Palestine

(Received 24 August 2009, revised 12 July 2010)

A series of 1,2,4,9,10,12-hexaazadispiro[4.2.4.2]tetradeca-2,10-dienes 5a–j was synthesized by the reaction of 1,4-cyclohexanedione dioxime (3) with appropriate nitrilimines (2). The microanalysis and spectral data of the synthesized compounds are in full agreement with their molecular structure. The microbial features of some of the synthesized compounds were studied by a known method.

Keywords: Dispiroheterocycles; 1,4-cyclohexanedione oxime; nitrilimines; cycloaddition.

J. Serb. Chem. Soc. 75 (11) 1481–1489 (2010)
UDC 577.112+577.175.72:539.2:543.544; JSCS–4070; doi: 10.2298/JSC100330090L; Original scientific paper

An investigation of the different molecular forms of IGFBP-1 using immobilised metal-, immuno- and lectin-affinity chromatography
DRAGANA LAGUNDŽIN, ROMANA MASNIKOSA, GORAN MILJUŠ, DRAGANA ROBAJAC and OLGICA NEDIĆ

Institute for the Application of Nuclear Energy – INEP, University of Belgrade, Banatska 31b, 11080 Belgrade, Serbia

(Received 30 March, revised 2 July 2010)

The insulin-like growth factor-binding protein 1 (IGFBP-1) is a member of a fAMily of six homologous proteins that regulate the action of the insulin-like growth factors. IGFBP-1 is a 25 kDa protein that, in addition to its native form, may exist in several phosphoforms (30 kDa), which are predominant in the circulation of humans. Phosphorylation of IGFBP-1 is a post-translational modification that has a great influence on the action of IGF-I. IGFBP-1 forms multimers and complexes with α2-macroglobulin (α2M). Polymerisation of IGFBP-1 was also reported. In order to analyse and separate these IGFBP-1 molecular species, affinity chromatography methods were used in this study. The results demonstrated that most of the IGFBP-1 circulates in complexes with α2M, which can be isolated by affinity chromatography using immobilised anti-α2M antibodies. IGFBP-1/α2M complexes may be differentiated from IGFBP-1 dimer and multimers using lectin-affinity chromatography, since the latter do not interact with lectins. It seems that the complexes contain not only monomeric IGFBP-1, but also its multimers. The dimer and multimers are stable under reducing conditions, suggesting a covalent linkage between the units. Free IGFBP-1 monomer can be separated from multimers using Con A-affinity chromatography. The concentration of free IGFBP-1 is relatively low in the circulation.

Keywords: IGFBP-1; isoforms; complexes; affinity chromatography.

J. Serb. Chem. Soc. 75 (11) 1491–1501 (2010)
UDC 635.74+549.742.114:615.322–188(560.4); JSCS–4071; doi: 10.2298/JSC100322115E; Original scientific paper

Sage-called plant species sold in Turkey and their antioxidant activitie
ILKAY ERDOGAN-ORHAN*, ELIF BAKI*^,**, SEZER ŞENOL* and GÜLDEREN YILMAZ**

*Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Ankara, Turkey

**Social Security Institution, Ministry of Labor and Social Security, Ankara, Turkey

***Department of Pharmaceutical Botany, Faculty of Pharmacy, Ankara University, 06100 Ankara, Turkey

(Received 22 March, revised 30 April 2010)

Sage is commonly consumed as a herbal tea in Anatolia, where not only Salvia species, but also Sideritis species are called “sage” by the local people. Therefore, it was decided to investigate the most common species of sage-called plants sold in aktars (traditional herb-selling stores). Eighty-seven sAMples randomly purchased from 21 provinces throughout Turkey were identified, which finally led to the identification of 7 species; Salvia tomentosa, Salvia fruticosa, Sideritis congesta, Sideritis pisidica var. termessi, Sideritis arguta, Sideritis perfoliata and Sideritis libanotica subsp. linearis. Infusions prepared from all sAMples were preliminarily tested for their antioxidant activity and 7 representative species were further evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferrous ion-chelating and ferric-reducing antioxidant power (FRAP) tests at 0.25, 0.50, and 1.0 mg ml^-1 and for their anti-acetylcholinesterase activity. The infusions were subjected to the DPPH bioautographic revelatory test, which led to the conclusion that a flavonoid derivative seemed to be responsible for the antioxidant activity in S. congesta and S. pisidica var. termessi.

Keywords: sage; Salvia; Sideritis; infusion; antioxidant; acetylcholinesterase.

J. Serb. Chem. Soc. 75 (11) 1503–1513 (2010)

J. Serb. Chem. Soc. 75 (11) 1515–1531 (2010)   

UDC 546.562’732’742+542.9+547.571+547.551:54–74:543.57; JSCS–4073; doi: 10.2298/JSC091113121D; Original scientific paper

J. Serb. Chem. Soc. 75 (11) 1533–1548 (2010)

UDC 635.71:616.936:530.145:543:51–3; JSCS–4074; doi: 10.2298/JSC100126124F; Original scientific paper

J. Serb. Chem. Soc. 75 (11) 1549–1557 (2010)

UDC 546.791.6+546.795.4+546.141+546.181–31:66.061:620.168.3; JSCS–4075; doi: 10.2298/JSC090617118G; Original scientific paper

Extraction and separation of U(VI) and Th(IV) from hydrobromic acid media using Cyanex-923 extractant

SNEHAL M. GHAG and SURESH D. PAWAR

Department of Chemistry, Siddharth College of Arts, Science and Commerce, Dr. D. N. Road, Fort, Mumbai – 400 001, India

(Received 17 June 2009, revised 12 July 2010)

A systematic study of the solvent extraction of uranium(VI) and thorium(IV) from hydrobromic acid media was performed using the neutral phosphine oxide extractant Cyanex-923 in toluene. These metal ions were found to be quantitatively extracted with Cyanex-923 in toluene in the acidity range 510-5–1×10^-4 M and 5×10^-5–5×10^-3 M, respectively, and they are stripped from the organic phase with 7.0 M HClO₄ and 2.0–4.0 M HCl, respectively. The effect of the equilibrium period, diluents, diverse ions and stripping agent on the extraction of U(VI) and Th(IV) was studied. The stoichiometry of the extracted species of these metal ions was determined based on the slope analysis method. The extraction reactions proceed by solvation and their probable extracted species found in the organic phase were UO₂Br₂•2Cyanex-923 and ThBr4•2Cyanex-923. Based on these results, a sequential procedure for their separation from each other was developed.

Keywords: solvent extraction; uranium(VI); thorium(IV); Cyanex-923; strip-ping; separation.

J. Serb. Chem. Soc. 75 (11) 1559–1574 (2010)

UDC 547.262+66.094.3:546.92+544.478:539.12; JSCS–4076, doi: 10.2298/JSC100519093T; Original scientific paper

Comparative study of ethanol oxidation at Pt-based nanoalloys and UPD-modified Pt nanoparticles

AMALIJA V. TRIPKOVIĆ, JELENA D. LOVIĆ and KSENIJA DJ. POPOVIĆ

ICTM – Institute of Electrochemistry, University of Belgrade, Njegoševa 12, P.O. Box 473, 11000 Belgrade, Serbia

(Received 19 May, revised 30 June 2010)

The activity of two alloys, Pt₃Sn/C and Pt₃Ru₂/C, was compared with the activity of Pt/C modified with corresponding AMounts of Sn_UPD (≈25 %) and Ru_UPD (≈40 %) in the oxidation of ethanol. Pt₃Sn/C, Pt₃Ru₂/C and Pt/C catalysts were characterized by XRD analysis. To establish the activity and stability of the catalysts, potentiodynAMic, quasi steady-state and chronoAMperometric measurements were performed. Both alloys are more active than Sn_UPD- or Ru_UPD-modified Pt/C catalysts. The electronic effect determining dominantly the activity of Pt₃Sn/C is the main reason for its higher activity compared to Pt₃Ru₂/C. Since Sn_UPD and Ru_UPD do not provoke any significant modification of electronic environment, both modified Pt/C catalysts were less active than the corresponding alloys. More pronounced difference in activity between Pt₃Sn/C and Sn_UPD-modified Pt/C than between Pt₃Ru₂/C and Ru_UPD-modified Pt/C is caused by the electronic effect in Pt₃Sn/C. The high activity of Pt₃Sn/C modified with a small AMount of Sn_UPD (≈10 %) can be explained by combining the electronic effect, causing less strongly bonded adsorbate on Pt sites and easier mobility of the Sn_UPD, with an enhanced AMount of oxygen-containing species on the Sn sites, resulting finally in a reinforcement of the bifunctional mechanism.

Keywords: ethanol oxidation; platinum–tin nanocatalyst; platinum–ruthenium nanocatalyst, platinum nanocatalyst; underpotential deposition.

J. Serb. Chem. Soc. 75 (11) 1575–1582 (2010)

UDC 628.1.033:543.551+543.554:544.362.2:544.6.076.32–43; JSCS–4077; doi: 10.2298/JSC100316094D; Original scientific paper

Coulometric–potentiometric determination of the autoprotolysis constant and the relative acidity scale of water

RADMILA M. DŽUDOVIĆ and LJILJANA N. JAKŠIĆ*

Faculty of Sciences, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac, Serbia

*University of Belgrade, Faculty of Mining and Geology, Đušina 7, 11000 Belgrade, Serbia

(Received 16 March, revised 6 July 2010)

The autoprotolysis constant and the relative acidity scale of water were determined by applying the coulometric–potentiometric method and a hydrogen/palladium (H₂/Pd) generator anode. In the described procedure for the evaluation of the autoprotolysis constant, a strong base, coulometrically generated in situ at the platinum cathode in the electrolytic cell, in the presence of sodium perchlorate as the supporting electrolyte, was titrated with hydrogen ions obtained by the anodic oxidation of hydrogen dissolved in the palladium electrode. The titration was performed with a glass–SCE electrode pair at 25.0±0.1 °C. The obtained value, pK_w = 13.91±0.06, is in agreement with literature data. The range of the acidity scale of water was determined from the difference between the half-neutralization potentials of the electrogenerated perchloric acid and that of sodium hydroxide in a sodium perchlorate medium. The half-neutralization potentials were measured using both a glass–SCE and a (H₂/Pd)_ind–SCE electrode pair. A wider range of the relative acidity scale of water was obtained with the glass–SCE electrode pair.

Keywords: coulometry; potentiometry; autoprotolysis constant; relative acidity scale; hydrogen–palladium electrode.

J. Serb. Chem. Soc. 75 (11) 1583–1594 (2010)

UDC Digoxin+544.35+543.544.5.068.7; JSCS–4078; doi: 10.2298/JSC100106123M; Original scientific paper

An HPLC method for the determination of digoxin in dissolution sAMples

MIROSLAV Ž. MILENKOVIĆ, VALENTINA D. MARINKOVIĆ, PREDRAG S. SIBINOVIĆ, RADOSAV M. PALIĆ* and DRAGAN M. MILENOVIĆ

Pharmaceutical and Chemical Industry Zdravlje-Actavis, Vlajkova 199, Leskovac, Serbia

*Department of Chemistry, Faculty of Science and Mathematics, University of Niš, Višegradska 33, Niš, Serbia

(Received 6 January, revised 13 September 2010)

An HPLC method for digoxin quantification in dissolution sAMples obtained as per the official British Pharmacopeia (BP) method is presented in this paper. The chromatography was performed at 20 °C on a Symmetry C18; 3.5 mm, 75 mm×4.6 mm column with water–acetonitrile (72:28, v/v), as the mobile phase and UV detection at 220 nm. The method was found to be selective, linear, accurate and precise in the specified ranges. The LOD and LOQ were 0.015 and 0.050 µg mL^-1, respectively. Robustness testing was conducted to evaluate the impact of minor changes in the chromatographic parAMeters (i.e., acetonitrile fraction, flow rate of the mobile phase, column temperature and column length) on the characteristics of the digoxin peak. A full factorial design (2⁴) was used to investigate the influence of the four variables. The presented HPLC method was applied in quality and stability testing of digoxin tablets 0.25 mg.

Keywords: digoxin; tablets; dissolution testing; HPLC; validation; experimental design.

J. Serb. Chem. Soc. 75 (11) 1595–1605 (2010)

UDC 548.2+531.3+541.124+546.32’82’289’21:666.11; JSCS–4079; doi: 10.2298/JSC091118120G; Original scientific paper

Crystal growth of K₂TiGe₃O₉ in the glass

SNEŽANA R. GRUJIĆ, NIKOLA S. BLAGOJEVIĆ, MIHAJLO B. TOŠIĆ*, VLADIMIR D. ŽIVANOVIĆ* and ZAGORKA S. AĆIMOVIĆ-PAVLOVIĆ

Faculty of Technology and Metallurgy, 4 Karnegijeva St., 11000 Belgrade, Serbia

*Institute for Technology of Nuclear and other Mineral Raw Materials, Franchet d’ Esperey 86, 11000 Belgrade, Serbia

(Received 18 November 2009, revised 29 July 2010)

The kinetics and mechanism of isothermal crystal growth of K₂TiGe₃O₉ from a glass of the sAMe stoichiometric composition were studied. The crystal growth rate, U, in the range 1×10^-11–1.27×10^-10 m s^-1 was experimentally determined in the temperature interval 540–600 °C. In the range of high undercooling, Dt, 435–375 °C, spherical crystals growing at (374±19) kJ mol^-1 was observed.

Keywords: crystal growth; K₂TiGe₃O₉; kinetics; mechanism; glass.

J. Serb. Chem. Soc. 75 (11) 1605–1616 (2010)

UDC 665.73/.75+504.53.054:620.95:628.516; JSCS–4080; doi: 10.2298/JSC100505091B; Original scientific paper

Change of isoprenoids, steranes and terpanes during ex situ bioremediation of mazut on the industrial scale

VLADIMIR P. BEŠKOSKI*, MILOŠ TAKIĆ**, JELENA MILIĆ*, MILA ILIĆ*, GORDANA GOJGIĆ-CVIJOVIĆ*, BRANIMIR JOVANČIĆEVIĆ*^,** and MIROSLAV M. VRVIĆ*^,**

*Department of Chemistry, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12, P.O. Box 473, 11001 Belgrade, Serbia

**Faculty of Chemistry, University of Belgrade, Studentski trg 16, P.O. Box 51, 11158 Belgrade, Serbia

(Received 5 May, revised 22 June 2010)

This paper presents the results of an ex situ bioremediation of soil contAMinated by mazut (heavy residual fuel oil) in the field scale (600 m³). The treatment-bed (thickness 0.4 m) consisted of mechanically mixed mazut-contAMinated soil, softwood sawdust as an additional carbon source and crude river sand, as a bulking and porosity increasing material. The inocula-tion/reinoculation was conducted periodically using a biomass of a consortium of zymogenous microorganisms isolated from a bioremediation substrate. The biostimulation was performed through addition of nutritious substances (N, P and K). The aeration was improved by systematic mixing of the bioremediation system. After 50 days, the number of hydrocarbon degraders had increased a 100 fold. Based on the changes in the group composition, the average biodegradation rate during bioremediation was 24 mg kg^-1 day^-1 for the aliphatic fraction, 6 mg kg^-1 day^-1 for the aromatic fraction and 3 mg kg^-1 day^-1 for the nitrogen–sulphur–oxygen compounds (NSO)–asphaltene fraction. In the saturated hydrocarbon fraction, gas chromatography–mass spectrometry (GC–MS) in the single ion-monitoring mode (SIM) was applied to analyse isoprenoids pristane and phytane and polycyclic molecules of sterane and triterpane type. Biodegradation occurred during the bioremediation process, as well as a reduction of the relative quantities of isoprenoids, steranes, tri- and tetracyclic terpanes and pentacyclic terpanes of the hopane type.

Keywords: mazut; bioremediation; field experiment; zymogenous microbial consortia; isoprenoids, steranes and terpanes.

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