Acta Chimica Slovenica

Due to its transferability, the soil has been commonly used as evidence in criminal investigations. In this work, 172 soil samples taken from five urban parks from the town of Tetovo (North Macedonia) and from additional four rural locations in its vicinity. The soil samples were examined using X-ray powder diffraction. The collected diffractograms were used for development of classification models based on supervised self-organizing maps. The examination generalization performances of the developed models showed that they were able to correctly classify between 95...

Four new fluoro-containing hydrazones were synthesized from 4-fluorobenzaldehyde with chloro- and nitro-substituted benzohydrazides. They are 3-chloro-N'-(4-fluorobenzylidene)benzohydrazide (1), 2-chloro-N'-(4-fluorobenzylidene)benzohydrazide (2), N'-(4-fluorobenzylidene)-4-nitrobenzohydrazide (3), and N'-(4-fluorobenzylidene)-3-nitrobenzohydrazide (4). The compounds have been characterized by IR and 1H NMR spectra, as well as X-ray single crystal determination. Xanthine oxidase (XO) inhibitory activity indicated that the nitro substituted compounds 3 and 4 have effective activity...

Extraction of bioactive compounds from Withania somnifera roots was studied using sodium acetate-glycerol deep eutectic solvent (DES) and two techniques ultrasound-assisted extraction (UAE) and heat-assisted extraction (HAE) under response surface methodology (RSM). For UAE and HAE, total phenolic content (TPC, mg gallic acid equivalents per g dry weight (mg GAE g-1 DW)), total flavonoid content (TFC, mg rutin equivalents g-1 DW (mg RE g-1 DW)), radical scavenging activity (RSA, mg AAE (ascorbic acid equivalents) g-1 DW), and iron chelating activity (ICA, mg EDTAE (ethylenediaminetetraacetate equivalents) g-1 DW%) were 6...

Synthesis and anticholinesterase activity of 18 previously unpublished indole- and tryptophan-derived compounds are disclosed. These sp3-rich compounds containing an indole structural unit exhibit selective submicromolar inhibition of human butyrylcholinesterase (hBChE). The structures of the newly synthesized compounds were confirmed by 1H and 13C NMR, IR spectroscopy, and high-resolution mass spectrometry.

A potentiometric investigation has been carried out to disclose the coordination properties of Dacarbazine, 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboxamide (abbreviated DTIC) with particular transition metal ions (Zn2+, Cu2+, Ni2+ and Co2+). The coordination of DTIC with these metal ions results in several complexes emerging in solution. The aim of this work is to determine the protonation constants of the DTIC and to show the extent of its coordination with (Zn2+, Cu2+, Ni2+ and Co2+), in other words, establish the stability of the complexes formed between the DTIC and these metal ions by the determination of their stability constants...

2-Hydroxybenzaldehyde 4,S-diallylisothiosemicarbazone (HL) was synthesized and characterized by 1H, 13C NMR and FTIR spectroscopies. It exists in solution in two isomeric forms: cis (~25%) and trans (~75%). Six stable complexes were obtained by interaction of HL with copper(II), nickel(II), cobalt(III) and iron(III) salts: [Cu(L)Cl] (1), [Cu(L)NO3] (2), [Cu(3,4-Lut)(L)NO3] (3), [Ni(L)OAc] (4), [Co(L)2]Cl (5), [Fe(L)2]NO3 (6). The synthesized complexes have been studied by elemental analysis, FTIR, molar electrical conductivity and single crystal X-ray diffraction (6)...

Four new complexes of copper(II), nickel(II) and zinc(II), [CuL2] (1), [Ni3L2(4-BrSal)2(CH3COO)2(CH3OH)2]·2CH3OH (2), [ZnBr2(HL)2] (3) and [ZnL(dca)]n (4), where L is 5-bromo-2-((cychlopentylimino)methyl)phenolate, HL is the zwitterionic form of 5-bromo-2-((cychlopentylimino)methyl)phenol, 4-BrSal is the monoanionic form of 4-bromosalicylaldehyde, dca is dicyanamide anion, were synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopy. The structures of the complexes were further confirmed by single crystal X-ray structure determination...

For carbon steel X70 in a 1 M hydrochloric acid solution, Scorzonera undulata acetate extract (SUAc) was investigated as an ecological corrosion inhibitor. The anti-corrosion effect of Scorzonera undulata extract is studied using potentiodynamic polarization analysis and electrochemical impedance spectroscopy (EIS). The polarization curves clearly show that the extract is an excellent mixed inhibitor. Our findings show that the maximum inhibition efficiency of 83% has been found with inhibitor concentration up to 400 mg/L at 298 Kelvin...

In this study, activated carbon (AC) was prepared from pistachio nut shell precursor as agricultural by-product. The prepared AC was used to synthesize an efficient nanocomposite via loading of the copper metal and magnetic nanoparticles (Cu-MAC@C4H8SO3H NCs) onto its structure. The structure of the nanocatalyst was characterized by different methods such as FT-IR, TEM, EDS, XRD, VSM, and TGA analysis. The catalytic activity of the prepared composite was tested in a special C-S coupling, namely with the reaction of 2-mercapto-3-phenylquinazolin-4(3H)-one with iodobenzene or bromobenzene...

No abstract text is available yet for this article.

For polymeric materials, the relaxation spectrum contains complete information about the time-dependent part of the material response. The contribution of different numerical schemes, i.e., different methods of reconstructing the dynamic relaxation modulus, to the accuracy of the approximation by calculating the corresponding relaxation spectra is investigated by analysing experimental data for four types of polysaccharides. It was found that there is no unique mathematical approach for the calculation of relaxation spectra that ensures a satisfactory approximation of the experimentally determined dynamic moduli for the selected types of polymeric materials...

No abstract text is available yet for this article.

Rheumatoid arthritis has long been treated with acetylsalicylic acid, despite many side effects, including gastric ulcers. These side effects can be curtailed by preparing the metal complexes of8 acetylsalicylic acid, such as copper (II)-acetylsalicylate (CAS). Present study evaluates the pharmacokinetics parameters of CAS and the level of copper at extended dose levels using rabbit model. The concentrations of CAS and copper in plasma samples were determined by validated HPLC and atomic absorption spectroscopic (AAS) methods, respectively...

A star-shaped polymer (Star-PEG-PCL2) was synthesized with PCL and PEG and used as a stationary phase for gas chromatography. The statically coated Star-PEG-PCL2 column exhibited an efficiency of 2260 plates/m determined by naphthalene at 120 °C and moderate polarity. The Star-PEG-PCL2 column showed high resolution performance for isomers of a wide ranging polarity, including methylnaphthalenes, halogenated benzenes, nitrobenzene, phenols, and anilines, and displayed dual-nature selectivity for a mixture of 17 analytes...

Two copper(II) complexes of 4-chloro- and 4-dimethylaminobenzaldehyde nicotinic acid hydrazones were prepared and characterized by elemental analysis, mass spectrometry, infrared and electron spectroscopy and conductometry. These rare examples of bis(hydrazonato)copper(II) complexes are neutral complex species with copper(II) center coordinated with two monoanionic bidentate O,N-donor hydrazone ligands coordinated in enol-imine form. The interaction of hydrazone ligands and corresponding copper(II) complexes with CT DNA and BSA was investigated...

One of the disadvantages of voltammetric analysis is the significant amount of sample required for electrolysis in the cell. In this paper a methodology close to adsorption stripping voltammetry was proposed to solve this problem at an analysis of two azo dyes - Sunset Yellow FCF and Ponceau 4R. As a working electrode, a carbon-paste electrode modified with β-cyclodextrin, a cyclic oligosaccharide that can form supramolecular complexes with azo dyes was proposed. The redox behavior of Sunset Yellow FCF and Ponceau 4R, the number of electrons, protons, and charge transfer coefficients onto the proposed sensor have been studied...

Efficiencies of direct ozonation and hydroxyl radical oxidation by Fenton process were compared, aiming to improve biotreatability of antibiotics contaminated water (tiamulin, amoxicillin and levofloxacin).  Biodegradability, COD (chemical oxygen demand) and TOC (total organic carbon) were measured before and after applying oxidative process. It was confirmed that significantly smaller molar dose of ozone (1.1 mgO3 / mgatb) against the hydrogen peroxide (17 mgH2O2 / mgatb), deliver comparable improvements of biodegradability; Tiamulin biodegraded up to 60 %, levofloxacin close to 100 %...

Three new zinc(II) complexes, [Zn3(μ2-η1:η1-OAc)2(μ2-η2:η0-OAc)2L2] (1), [Zn3(μ2-η1:η1-OAc)2(μ1,1-N3)(N3)L2] (2), [Zn2(μ1,3-N3)(N3)(H2O)L2] (3), with the Schiff base ligand 4-chloro-2-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol (HL) have been synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopic studies. Crystal structures of the complexes were confirmed by single crystal X-ray diffraction. Complex 1 is a bidentate acetato, monoatomic bridging acetato, and phenolato co-bridged trinuclear zinc compound...

The presence of emerging substances in surface water is of a great concern knowing they are the main source for community water supply needs. This study describes the development, optimization and application of an analytical method for the determination of ibuprofen in the Danube samples. Caffeine concentrations, as an indicator of human waste, were determined and maximum risk indexes for aquatic organisms were calculated. The Danube samples were collected from ten representative locations. A Solid-phase extraction was used for ibuprofen and caffeine separation and the analysis was performed by High-performance liquid chromatography method...

A mononuclear methyl maltolate (Hmm) coordinated oxidovanadium(V) complex [VOL1(mm)] (1), and a mononuclear ethyl maltolate (Hem) coordinated oxidovanadium(V) complex [VOL2(em)] (2), where L1 and L2 are the dianionic form of N'-(2-hydroxy-5-methylbenzylidene)-3-trifluoromethylbenzohydrazide (H2L1) and N'-(2-hydroxy-5-methylbenzylidene)-4-trifluoromethylbenzohydrazide (H2L2), respectively, have been prepared. The hydrazones and the complexes were characterized by elemental analysis, FT-IR and UV-Vis spectra...