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Compounds used in the fashion industry effect the water bodies in the vicinity of textile factories, resulting in the visible coloration of surface water. Fe-doped graphite-based in house prepared electrodes were used in the Fenton- -like degradation of Reactive Blue 52 (RB52). The electrodes consisting of high-density graphite in three granulation sizes and three levels of Fe content were characterized using scanning electron microscopy (SEM). The amount of Fe in the electrodes and H2O2 concentration in synthetic textile wastewater were optimized. Additionally, the size of graphite grains was varied to investigate whether it effects the degradation rate. Under only 10 min of electro-Fenton degradation, a system with 10 mmol dm-3 of H2O2 and an electrode made of 7 % of Fe and 70 μm of granulation size of graphite, degraded over 75 % of RB52, and over 99 % after 40 min of treatment. The obtained results indicate that the proposed approach could be beneficial in the field of novel materials for environmental application and that in house prepared carbon could be an excellent replacement for commercially available supports.

A total of 14 novel arylpiperazines were synthesized, and pharmacologically evaluated by measuring their affinities towards the D2 dopamine receptor (DRD2) in a [3H]spiperone competition assay. All the herein described compounds consist of a benzimidazole moiety connected to N-(2-methoxyphenyl)piperazine via linkers of various lengths. Molecular docking analysis and molecular dynamics simulations were performed on the DRD2–arylpiperazine complexes with the objective of exploring the receptor–ligand interactions and properties of the receptor binding site. The recently published crystal structure of DRD2 was used throughout this study. The major finding is that high affinity arylpiperazines must interact with both the orthosteric binding site and the extended binding pocket of DRD2 and therefore should contain a linker of 5 or 6 methylene groups long. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172032]

Classical methods of wastewater treatment are often not suitable for the treatment of pharmaceutical waste. The previous studies have shown that the use of the advanced oxidation procedures (AOP) can lead to a more efficient degradation of various biologically active compounds, which are active pharmaceutical ingredients of applied drugs. The aim of this paper is the application of the plasma technology on the degradation of a two active pharmaceutical ingredients (APIs, diazepam and alprazolam) and the finished products (Bensedin® and Ksalol®) using the dielectric barrier discharge (DBD) reactor for AOP. We studied the degradation rate of these pharmaceuticals, depending on the number of passes through the reactor. This degradation method was efficient 61 % for diazepam and 95 % alprazolam. We also examined the influence of the pH adjustment between the passes of APIs through the DBD reactor. The degradation rate of APIs and the finished products was monitored by the high performance liquid chromatography (HPLC) technique, using a photodiode array detector. The concentration of the dissolved ozone was determined using the iodometric procedure. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172030]

Two anionic surfactants (sodium lauryl sulfate - SDS and sodium dodecylbenzenesulfonate - SDBS) were treated with dielectric barrier discharge. Loss of surfactant activity, decrease of chemical oxygen demand and total organic carbon as well as lower toxicity of degradation products were determined. Effects of catalysts - hydrogen peroxide and iron (II), on parameters mentioned above, were determined. Catalysts affect the degradation of SDBS and in the case of SDS catalysts have no effect on degradation. Both catalysts induce the decrease of COD and TOC values. Toxicity of solutions after the plasma treatment is lower in all the systems tested. [Projekat Ministarstva nauke Republike Srbije, br. OI 172030]

A series of sixteen novel substituted piperidines and (2-methoxyphenyl)piperazines were synthesized, starting from the key intermediates 1-(2-methoxyphenyl)-4-(piperidin-4-yl)piperazine and 1-(2-methoxyphenyl)-4-(piperidin-4-ylmethyl)piperazine. Biological evaluation of the synthesized compounds was pointed out for seven compounds, of which 1-(2-methoxyphenyl)-4-{[1-(2-nitrobenzyl)piperidin-4-yl]methyl}piperazine had the highest affinity for the dopamine D2 receptor. For all seven selected compounds docking analysis was performed in order to establish their structure-to-activity relationship. [Projekat Ministarstva nauke Republike Srbije, br. 172032]

Fe-doped TiO2 photocatalysts with different content of Fe (0.5, 1.6, 3.4 and 6.4%) were synthesized by the microwave-hydrothermal method and characterized by XRD, N2 physisorption at 77 K and DRS. The characterization showed that Fe ions are highly dispersed in the TiO2 lattice. It was found that all the synthesized catalysts had the mesoporous structure and Fe doping increased BET surface areas. The UV-Vis study showed that the absorption spectra shifted to a longer wavelength (red shift) with an increase in the dopant concentration. The photocatalytic activity of the samples was evaluated by the decolorization of textile dye Reactive Blue 52 (RB) in aqueous solutions under sun-like radiation in the presence of H2O2 (heterogeneous photo-Fenton process). The photocatalyst with 3.4% Fe was found to be the most efficient with H2O2. The effect of the initial pH of the dye solution was assessed and dissolution of iron ions was studied, as a function of pH value. It was concluded that decolorization is more favorable in acidic pH and when pH >4, the releasing of Fe ions in solution was negligible. Photocatalytic degradation of 4-chlorophenol (4-CP) was investigated under the optimal conditions and proved that our catalyst was capable to degrade colorless pollutants. [Projekat Ministarstva nauke Republike Srbije, br. 172030 i br. 172035]

Introduction. Infrared thermography or thermovision is increasingly applicable in sport and sport rehabilitation. Thermic forms, thermic imprints, temperature and isotherm distribution, temperature gradient change are the terms that are more and more often met in sport medicine and medicine, in general. Case report. We presented two examples of thermovision application: in detection of muscle injury and changes of the feet exposed to low temperature. In the first example the thermovision method was used for analyzing heat distribution in an athlete with back muscles injury. With a special original method of local cooling the place and degree of injury was precisely localized and determined, respectively, regardless high environmental temperature. In the second case the thermovision method was for the first time applied in a runner whose feet was exposed to low temperature. Significant hypothermia of the feet was detected by the method and appropriate treatment was performed. Thanks to this the athlete had no harmful consequences. Conclusion. Thermovision is fast and efficient in detecting different kind of injuries, so its increased use in the future can be expected.

Second extracellular loop (ecl2) of dopamine (DA) D2 receptor is an essential part of dopaminergic ligands binding pocket. To form a part of the ligand binding surface it has to fold down into the transmembrane domain of the DA receptor. The current study describes the modeling of the D2 DA receptor ecl2 and its interactions with arylpiperazine ligands. In order to model D2 DA receptor ecl2, the number of arylpiperazine ligands was used to propose pharmacophore model. D2 DA receptor ecl2 model was built using Accelrys Discovery Studio. To test the proposed model, docking analysis was performed and key amino acid residues were determined. Proposed receptor-ligand iteractions were rationalized and compared with measured binding affinity. It is shown that D2 DA receptor ecl2 significantly participates in receptor-ligand complex formation through aromatic, hydrophobic and polar interaction. Taking them in account would benefit GPCR molecular modeling and facilitate the design of novel active compounds.

A thin-layer chromatographic method with densitometric detection was established for quantification of p-chlorophenol in waste water. Degradation efficiency of p-chlorophenol was monitored after each treatment of the wastewater samples. Degradation of p-chlorophenol was performed with advanced oxidation processes (AOPs), using UV, H2O2/UV, O3/H2O2/UV, O3 and O3/UV. Developed TLC procedure has been found to be simple, rapid and precise. The method was characterized by high sensitivity (limit of detection was 11 ng per band and limit of quantification 35 ng per band), linear range (from 75 to 500 ng per band, r = 0.9965), and high precision, accuracy (mean percentage recovery 98.6%), and specificity. Additionally, the efficiency of degradation was monitored using HPLC giving comparable results with RP TLC measurements. [Acknowledgement. This work was performed within the framework of the research project No. 172017 supported by the Ministry of Education and Science of Serbia.]

Inorganic salts improve the coloration of textiles, which increase pollution load on dyehouse effluent in general. Decolorization of reactive textile dye C.I. Reactive Black 5 was studied using Advanced Oxidation Processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film Dielectric Barrier Discharge (DBD). Initial dye concentration in the solution was 40.0 mg L-1. The effects of addition of inorganic salt different high concentrations (NaCl, Na2SO4 and Na2CO3) on the degree of decolorization were studied. Recirculation of dye solution through the DBD reactor with applied energy density 45-315 kJ L-1 was used. The influence of residence time was investigated after 5 minutes and 24 hours of plasma treatment. Decolorization of the dyes was monitored by spectrophotometric measurement. Changes of pH values and the conductivity of dye solution after each recirculation were tested. The most effective decolorization of over 90% was obtained with the addition of NaCl (50 g L-1), applied energy density of 135 kJ L-1 and after residence time of 24 hours of plasma treatment. Decolorization of solutions containing inorganic salts Na2SO4 and Na2CO3 were lower than for the solution without salt.

Arsenic reduction in drinking water can include treatment by adsorption, switching to alternative water sources, or blending with water that has a lower arsenic concentration. Commercial sorbents MTM, Greensand and BIRM (Clack Corporation) were modified with zirconium and titanium after activation. The modifications were performed with titanium tetrachloride and zirconium tetrachloride. The modified sorbents were dried at different temperatures. The sorption of arsenate and arsenite dissolved in drinking water (200μg L-1) onto the sorbents were tested using a batch procedure. After removal of the sorbent, the concentration of arsenic was determined by HG-AAS. Zirconium-modified BIRM showed the best performance for the removal of both arsenite and arsenate. Modification of the greensand did not affect arsenic sorption ability. Zirconium-modified BIRM diminished the concentration of total As to below 5 μg L-1.

Several isosteric 1,3-dihydro-5-[2-(4-aryl-1-piperazinyl)ethyl]-2H-benzimidazole-2-thiones were used to investigate the interactions of different ligands with the binding site of the D2 receptor. Due to limitations of the simulation methods, docking analysis failed to show precisely the interactions that influence the binding affinity of the ligands. It is presumed that dispersive forces or more precisely edge-to-face interactions play an important role in the binding process, especially for the lipophilic part of the ligands. In order to confirm this hypothesis, ab initio calculations were applied on a model system in order to find the stabilization energies of potential edge-to-face interactions and then to correlate them with the ligand affinity. The obtained results indicate that there is a significant correlation between the strength of dispersive interactions and ligand affinity. It was shown that for the calculation of stabilization energies of modeled receptor-ligand complexes the Becke 'half-and-half' hybrid DFT method can be used, thus speeding up the usually long calculation time and reducing the required computer strength.

Six newly synthesized heterocyclic (2-nitrophenyl)piperazines, with a specific structure of the heteroaryl group, whichmimics the catechol moiety of dopamine (benzimidazoles and substituted benzimidazoles), were evaluated for their binding affinity to rat dopamine (DA), serotonin (5-HT) and _1 receptors. All compounds with a benzimidazole group had a 5-HT2A/D2 receptors binding ratio characteristic for atypical neuroleptics (>1, pK i values). Compound 7c, 4-bromo-6-{2-_4-(2-nitrophenyl)piperazin- 1-yl_ethyl}-1H-benzimidazole, expressed higher affinities for all receptor classes than clozapine. Also, it exhibited the best characteristic for atypical neuroleptics and presents a compound with the best profile for further in vivo investigations.

Eight new compounds with halogen atom introduced into the benzimidazole- 2-thione dopaminergic pharmacophore of 5-[2-(4-arylpiperazin-1-yl)ethyl]-1,3-dihydro- 2H-benzimidazole-2-thiones with the arylpiperazine part of the molecule being selected according to known structure-affinity requirements, have been synthesized. All the new compounds were evaluated for the in vitro binding affinity at the dopamine (DA) D1 and D2 and serotonin 5-HT1A receptors by the competitive radioassays, performed on synaptosomal membranes prepared from fresh bovine caudate nuclei and hippocampi. All the new compounds were strong competitors for the binding of the radioligands to the D2 and 5-HT1A receptors, with the most active of them having 34 and 170 time higher affinity than non-halogenated congeners in the D2 DA receptor radioassays (compounds 9.1b and 9.2b, respectively). Divergently, these compounds were without significant affinities for the D1 DA receptors. .

Nanoparticles of TiO2 are suitable for many catalytic and photocatalytic applications due to their extraordinary properties such as superhydrophobicity, semiconductivity, electron-rich, and environmental compatibility. The main crystalline phases of TiO2, anatase, and rutile possess different crystal structures, crystallinity, crystalline sizes, and specific surface areas, and these characteristics directly affect the catalytic performance of TiO2. In the present study, domestic carbon material enhanced with TiO2 nanoparticles was synthesized and used for the construction of a modified carbon paste electrode. The electrocatalytic activity of the modified electrodes was investigated depending on the TiO2 crystalline phases in the electrode material. Furthermore, the obtained working electrode was utilized for triclosan detection. Under optimized experimental conditions, the developed electrode showed a submicromolar triclosan detection limit of 0.07 µM and a wide linear range of 0.1 to 15 µM. The relative standard deviations for repeatability and reproducibility were lower than 4.1%, and with satisfactory selectivity, the proposed system was successfully applied to triclosan monitoring in groundwater. All these results confirm that the sustainable production of new and domestically prepared materials is of great benefit in the field of electrocatalysis and that the morphology of such produced materials is strongly related to their catalytic properties. [ABSTRACT FROM AUTHOR]

Serotonin receptors (5-HTRs), especially the 5-HT1A subtype, have been the subject of intensive research for the past decade, due to their function in human physiology. Several structurally different classes of ligands are known to bind to the 5-HT1A receptor, but arylpiperazine derivatives are among the most important ligands. In the work, docking analyses were used to explain the binding affinities of a series of ligands with different N-1 substituent. All ligands had in common the arylpiperazine structure, while the N-1 subsistent was modified to investigate the influence of ligand structure on its binding affinity. The shape and size, as well as the rigidity of the subsistents were altered to investigate the possible effects on the formation of the receptor - ligand complex.

An efficient synthesis of methyl 4-[(1-oxopropyl)phenylamino]piperidine-4-carboxylate (7) has been developed starting from 1-benzylpiperidin-4-one (1). The compound is a key intermediate in the synthesis of new generation, highly active narcotic analgesics, such as remifintanil, as well as the novel classes of fentanyl analogues. An optimized Strecker-type condensation of piperidone 1 with aniline and HCN yielded the anilino-nitrile 2(≈90%) which, upon selective hydrolysis with conc. H2SO4, gave the anilino-amide 3.After vigorous basic hydrolysis of 3, followed by acidification and successive treatment with SOCl2 and MeOH, the anilino-ester 5 was obtained (40–45%, in 3 steps). N-Acylation of 5 with propionyl chloride yielded the anilido-ester 6(70–80%) In the final step, the catalytic N-debenzylation of 6 was examined under various conditions and optimized to yield 7 in near quantitative yields.