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In this paper, three different Zn(II) complexes with (E)-2-(2-(1-(6-bromopyridin-2-yl)ethylidene)hydrazinyl)-N,N,N-trimethyl-2-oxoethan-1-aminium chloride (HLCl) have been synthesized and characterized by single crystal X-ray diffraction, elemental analysis, IR and NMR spectroscopy. All complexes are mononuclear, with the ligand (L) coordinated in a deprotonated formally neutral zwitterionic form via NNO donor set atoms. Complex 1 forms an octahedral geometry with the composition [ZnL2](BF4)2, while complexes 2 [ZnL(NCO)2] and 3 [ZnL(N3)2] form penta-coordinated geometry. Density functional theory (DFT) calculations were performed to enhance our understanding of the structures of the synthesized complexes and the cytotoxic activity of the complexes was tested against five human cancer cell lines (HeLa, A549, MDA-MB-231, K562, LS 174T) and normal human fibroblasts MRC-5. Additionally, antimicrobial and antifungal activity of these complexes was tested against a panel of Gram-negative and Gram-positive bacteria, two fungal strains, and a yeast strain. It is noteworthy that all three complexes show selective antifungal activity comparable to that of amphotericin B. Molecular docking analysis predicted that geranylgeranyl pyrophosphate synthase, an enzyme essential for sterol biosynthesis is the most likely target for inhibition by the tested complexes.

INTRODUCTION and OBJECTIVES: Remote sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance, and in a narrower sense includes the analysis and interpretation of various images of parts of the Earth's surface. The application of satellite images with modern technology and software is possible in all phases of research of various natural phenomena, and their analysis are carried out by computer-aided and visual procedures. The aim of this research is to present the basic aspects of remote sensing and modern technologies in assessing the water supply of natural grasslands, as well as the presentation of possibility for faster data collection while reducing costs, and easier understanding of the whole research area. MATERIAL and METHOD: The trial was set on March 22nd of 2022 on a natural grassland in the village of Mitrovo polje on the mountain Goč (43° 30′ 22′ N latitude, 20° 52′ 26′ E longitude, 700 m a.s.l.) in the Aleksandrovac municipality. Disturbed and undisturbed soil samples were collected to determine soil texture, soil water retention characteristics and soil chemical properties. Continuous measurement of soil moisture was performed with TDR probes in three replicates and sensors for monitoring soil temperature were installed. The satellite images (SENTINEL 2) with a resolution 10 m, in a time interval of about a week, created in relatively clear weather (cloudiness <30%), starting from March 22 to May 21st were used, while soil moisture data were collected on a daily basis. Data on precipitation and air temperature for the observed period were taken from the Agrosens portal. The supply of natural grassland with water and assessment of soil moisture are determined by the index of normalized difference vegetation index (NDVI), as the most applicable vegetation index. NDVI is defined as the ratio of differences between individual values of reflective wavelengths o

Fe(III) and Mn(II) complexes with condensation product of thiosemicarbazide and 2-acetylthiazole (HL1, (E)-2-(1-(thiazol-2-yl)ethylidene)hydrazine-1-carbothioamide) have been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, and elemental analysis. In both complexes, the thiosemicarbazone ligand is coordinated in deprotonated form through the NNS donor set of atoms. However, while Fe(III) complex is in the doublet ground state with distorted octahedral geometry, the coordination environment around Mn(II) is distorted trigonal-prismatic, and the sextet state is found to be the ground state. DFT calculations were performed to rationalize spin state preferences, and continuous shape measure describes the deviation from ideal six-coordinated polyhedral geometries in the ground and excited states. Antimicrobial activity (against a panel of Gram-negative and Gram-positive bacteria, two yeast, and one fungal strain), brine shrimp assay, and DPPH radical scavenging activity of both complexes were evaluated, and these results relate to the electronic structure of the complexes., Additional crystallographic and computational results, and the Cartesian coordinates of all DFT optimized structures

In this paper, the previously synthesized Cu(II) complex ([CuL1(N3) (CH3OH)]BF4) with N,N,N-trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride, has been characterized and its biological activity has been studied in detail. The Cu(II) complex consists of ligand coordinated in a deprotonated, formally neutral zwitter-ionic form, via NNO atoms, one azido ligand and one methanol molecule. The Cu(II) complex was selected due to results of the cytotoxic activity, the brine shrimp test and DPPH radical scavenging activity, which were previously performed. The effects of Cu(II) complex on cell cycle phase distribution of cervical adenocarcinoma HeLa cells were investigated in order to examine the mechanisms of its anticancer activity. The measurement of intracellular ROS levels in HeLa and HaCaT cell lines were evaluated in order to explore their possible generation and the role in cytotoxic activity. The possible anti-invasive and anti-angiogenic properties of Cu(II) complex were evaluated. DNA binding experiments, including fluorescence displacement study and DNA cleavage experiments, were performed in order to obtain information on the type of DNA-metal complex interactions. © 2022 Serbian Chemical Society. All rights reserved.

The HL ligand was synthesized in the reaction of thiosemicarbazide and 2-acetylthiazole in molar ratio 1:1 in water, with 3 drops of 2M HCl. Complex [Fe(L)2]BF4·H2O (1) was synthesized in the reaction of ligand and Fe(BF4)6·6H2O in MeOH, after complete dissolution of Fe(BF4)2·6H2O in the reaction mixture, NaN3 was added. In the reaction of ligand (HL), MnCl2·4H2O and NaN3, in molar rotio 1 : 1 : 4, Mn(II) complex (2) was obtained. Complexes 1 and 2 were characterized by elemental analysis, IR and UV/Vis spectroscopy and X-ray crystallographic analysis. Both complexes 1 and 2 with HL ligand are bis octahedral complexes in which two deprotonated ligand molecules coordinate in a mer arrangement through two NNS sets of donor atoms, through thiazole and imine nitrogens and thioenolate sulfur., Ligand (HL) sintetisan je u reakciji tiosemikarbazida i 2-acetiltiazola u molarnom odnosu 1 : 1 u vodi, u kiseloj sredini. Kompleks [Fe(L)2]BF4·H2O (1) dobijen je u reakciji liganda i Fe(BF4)2·6H2O u metanolu i nakon potpunog rastvaranja Fe(II) soli dodat je NaN3 u višku (1 : 1 : 4). U reakciji liganda (HL), MnCl2·4H2O i NaN3 u molarnom odnosu 1 : 1 : 4, dobijen je kompleks Mn(II), [Mn(L)2] (2). Kompleksi 1 i 2 okarakterisani su elementalnom analizom, IC spektroskopijom, UV/Vis spektroskopijom i rendgenskom strukturnom analizom. Kod oba kompleksa 1 i 2 dolazi do forimiranja bis oktaedarske geometrije tako što se za centralni metalni jon koordinuju dva deprotonovana liganda preko dva NNS donorska seta atoma u mer okruženju. Do koordinacije liganda za centralni metalni jon, kako Fe(III), tako i Mn(II), dolazi preko dva azota, od kojih jedan potiče iz tiazola, a drugi iz iminske grupe, kao i preko sumpora iz tioenolatne grupe.

The HLCl ligand with metal salts Cu(BF4)2‧6H2O / MnCl2‧4H2O / Zn(BF4)2‧6H2O and NaN3, in methanol form mononuclear penta-coordinated complexes [CuL(N3)(CH3OH)]BF4 (1) and [ZnL(N3)2] (2) and binuclear [Mn2L2(µ-1,1-N3)2(N3)2]⋅2CH3OH (3) complex. Complexes 1, 2 and 3 were characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, and DFT calculations., U reakciji liganda HLCl sa solima metala Cu(BF4)2‧6H2O / MnCl2‧4H2O / Zn(BF4)2‧6H2O i NaN3 u metanolu, dobijeni su mononuklearni kompleksi koordinacionog broja pet: [CuL(N3)(CH3OH)]BF4 (1) i [ZnL(N3)2] (2) i dinuklearni kompleks [Mn2L2(µ-1,1-N3)2(N3)2]⋅2CH3OH (3). Kompleksi 1, 2 i 3 okarakterisani su elementalnom analizom, IC spektroskopijom, rendgenskom stukturnom analizom i DFT proračunima.

In this paper, the previously synthesized Cu(II) complex ([CuL1(N3) (CH3OH)]BF4) with N,N,N-trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride, has been characterized and its biological activity has been studied in detail. The Cu(II) complex consists of ligand coordinated in a deprotonated, formally neutral zwitter-ionic form, via NNO atoms, one azido ligand and one methanol molecule. The Cu(II) complex was selected due to results of the cytotoxic activity, the brine shrimp test and DPPH radical scavenging activity, which were previously performed. The effects of Cu(II) complex on cell cycle phase distribution of cervical adenocarcinoma HeLa cells were investigated in order to examine the mechanisms of its anticancer activity. The measurement of intracellular ROS levels in HeLa and HaCaT cell lines were evaluated in order to explore their possible generation and the role in cytotoxic activity. The possible anti-invasive and anti-angiogenic properties of Cu(II) complex were evaluated. DNA binding experiments, including fluorescence displacement study and DNA cleavage experiments, were performed in order to obtain information on the type of DNA-metal complex interactions. © 2022 Serbian Chemical Society. All rights reserved.

Recently, we synthesized silver(I) complex with the antifungal agent itraconazole, which showed improved anti-Candida potential and therapeutic safety in comparison to itraconazole and rescued zebrafish embryos affected by lethal C. albicans infection, when used in safe doses. Inspired by these results, in the present study, three new silver(I) complexes with clinically used azoles, econazole (ecz), clotrimazole (ctz) and voriconazole (vcz), [Ag(ecz)2]SbF6 (Ag1), [Ag(ctz)2]SbF6 (Ag2) and {[Ag(vcz)2]SbF6}n (Ag3) were synthesized and structurally characterized by elemental microanalysis, mass spectrometry, spectroscopy (1H NMR, IR and UV-Vis), cyclic voltammetry, molar conductivity measurements, and single crystal X-ray diffraction analysis. The spectroscopic and crystallographic results revealed that, in the synthesized silver(I) complexes, azole ligands are monodentately coordinated to the Ag(I) ion through the nitrogen atom forming [Ag(azole)2]+ complex cation. The antimicrobial effect of complexes and azole ligands was evaluated against different Candida species, as well as Gram-positive and Gram-negative bacteria. The synthesized complexes Ag1-3 exhibited good to moderate antimicrobial activity being, in most cases, more active than the corresponding azole ligands. Complexes Ag2 and Ag3 also showed strong inhibitory activity against C. albicans biofilm formation and strong inhibition of C. albicans filamentation at subinhibitory concentrations.

In a search for novel antimicrobial metal-based therapeutic agents, mononuclear gold(III) complexes 1-7 of the general formula [AuCl3(azole)], where azole stands for imidazole (im, 1), 1-isopropylimidazole (ipim, 2), 1-phenylimidazole (phim, 3), clotrimazole (ctz, 4), econazole (ecz, 5), tioconazole (tcz, 6) and voriconazole (vcz, 7) were synthesized, characterized and biologically evaluated. In all complexes, the corresponding azole ligand is monodentately coordinated to the Au(III) via the imidazole or triazole nitrogen atom, while the remaining coordination sites are occupied by chloride anions leading to the square-planar arrangement. In vitro antimicrobial assays showed that the complexation of inactive azoles, imidazole, 1-isopropylimidazole and 1-phenylimidazole, to the Au(III) ion led to complexes 1-3, respectively, with moderate activity against the investigated strains and low cytotoxicity on the human normal lung fibroblast cell line (MRC-5). Moreover, gold(III) complexes 4-7 with clinically used antifungal agents clotrimazole, econazole, tioconazole and voriconazole, respectively, have, in most cases, enhanced antimicrobial effectiveness relative to the corresponding azoles, with the best improvement achieved after complexation of tioconazole (6) and voriconazole (7). The complexes 4-7 and the corresponding antifungal azoles inhibited the growth of dermatophyte Microsporum canis at 50 and 25 mu g mL(-1). Gold(III) complexes 1-3 significantly reduced the amount of ergosterol in the cell membrane of Candida albicans at the subinhibitory concentration of 0.5 x MIC (minimal inhibitory concentration), while the corresponding imidazole ligands did not significantly affect the ergosterol content, indicating that the mechanism of action of the gold(III)-azole complexes is associated with inhibition of ergosterol biosynthesis. Finally, complexes 5 and 6 significantly reduced the production of pyocyanin, a virulence factor in Pseudomonas aeruginosa controlled by q

The paper presents an analytical solution for the non-isothermal compressible gas flow in a slide microbearing with different temperatures of walls. The gas flow is defined by the Navier-Stokes-Fourier system of the continuum equations and first order boundary conditions. Knudsen number corresponds to the slip and continuum flow (Kn lt = 10(-1)) and Reynolds number is moderately high, so inertia needs to be included. The solution is obtained by perturbations with the first approximation that relates to the continuum flow and the second one that involves second-order effects: the rarefaction, inertia, convection, dissipation, and rate at which work is done in compressing the element of fluid. The presented model analyzes the influence of the dependence of transport coefficients on temperature. The obtained analytical solution for the pressure, velocity, and temperature is approved by a comparison with the results of other authors. The microbearings can often be a part of MEMS, so the presented method and the obtained analytical solution can serve for solving similar non-isothermal shear-driven or pressure-driven problems. The paper gives an estimation about the error in values for microbearing mass flow and load capacity if the dependence of transport coefficients on temperature are neglected.

In this paper, the previously synthesized Cu(II) complex ([CuL1(N3) (CH3OH)]BF4) with N,N,N-trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride, has been characterized and its biological activity has been studied in detail. The Cu(II) complex consists of ligand coordinated in a deprotonated, formally neutral zwitter-ionic form, via NNO atoms, one azido ligand and one methanol molecule. The Cu(II) complex was selected due to results of the cytotoxic activity, the brine shrimp test and DPPH radical scavenging activity, which were previously performed. The effects of Cu(II) complex on cell cycle phase distribution of cervical adenocarcinoma HeLa cells were investigated in order to examine the mechanisms of its anticancer activity. The measurement of intracellular ROS levels in HeLa and HaCaT cell lines were evaluated in order to explore their possible generation and the role in cytotoxic activity. The possible anti-invasive and anti-angiogenic properties of Cu(II) complex were evaluated. DNA binding experiments, including fluorescence displacement study and DNA cleavage experiments, were performed in order to obtain information on the type of DNA-metal complex interactions. © 2022 Serbian Chemical Society. All rights reserved.

The ligand ([HL]Cl) was synthetized by the reaction of 2-acetylpyridine and Girard's P reagent in molar ratio 1:1 in ethanol. In the reaction of ligand ([HL]Cl), nickel(II) tetrafluoroborate hexahydrate and sodium azide [Ni(HL)(N3)3] complex was obtained. The Ni(II) ion has a distorted octahedral coordination geometry. The tridentate ligand (HL) is coordinated to the nickel ion with an NNO set of donor atoms forming two five-membered chelate rings and the other three coordination sites are supplemented by azido ligands. The ligand (HL) and the [Ni(HL)(N3)3] complex were characterized by elemental analysis, IR and UV/Vis spectroscopy and structure of the complex was defined by X-ray analysis.

In this work synthesis, characterization and crystal structures of 1, Zn(II) complex ([ZnL1(NCS)2]), with (E)-1-(2-oxo-2-(2-(quinolin-2-ylmethylene)hydrazinyl)ethyl)pyridin-1-ium chloride (HL1Cl) and 2, Bi(III) complex ([BiHL2Cl4] × 1/2CH3OH), with (E)-N,N,N-trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride (HL2Cl), have been reported. Zn(II) complex possesses a distorted trigonal bipyramidal geometry while surroundings around Bi(III) ion are extended pentagonal bipyramidal. Antimicrobial activity, brine shrimp assay and DPPH radical scavenging activity of both complexes, including previously synthesized complexes with HL2Cl ligand (Zn(II) and Ni(II)) and complexes with (E)-N,N,N-trimethyl-2-oxo-2-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride (HL3Cl) (Zn(II), Cu(II), Cd(II), Co(II), Fe(III), Ni(II)), were evaluated. For the most active complexes, cytotoxic activity against five malignant cancer cell lines (HeLa, A375, MCF7, PC-3 and A549) and normal cell line HaCaT, as well as generation of reactive oxygen species (ROS), was tested.

Five novel copper(ii) complexes with pyridine-4,5-dicarboxylate esters as ligands, [Cu(NO3)(py-2tz)(H2O)(3)]NO3 (1), [Cu(NO3)(2)(py-2metz)(H2O)] (2), [Cu(NO3)(2)(py-2py)(H2O)]center dot H2O (3), [CuCl2(py-2tz)](2) (4) and [CuCl2(py-2metz)](n) (5) (py-2tz is dimethyl 2-(thiazol-2-yl)pyridine-4,5-dicarboxylate, py-2metz is dimethyl 2-(4-methylthiazol-2-yl)pyridine-4,5-dicarboxylate and py-2py is dimethyl 2,2 '-bipyridine-4,5-dicarboxylate), were synthesized and structurally characterized by different spectroscopic and electrochemical methods. The structure of these complexes was determined by single-crystal X-ray diffraction analysis, confirming the bidentate coordination mode of the corresponding pyridine-4,5-dicarboxylate ester to the Cu(ii) ion through the nitrogen atoms. The antimicrobial potential of copper(ii) complexes 1-5 was assessed against two bacterial and two Candida species. These complexes showed better growth inhibiting activity against Candida spp. with respect to the tested bacterial species, also being moderately toxic towards normal human lung fibroblast cells (MRC-5). Complexes 1 and 4 showed the greatest ability to inhibit the filamentation of C. albicans, which is an important process during fungal infection, and these two complexes efficiently inhibited the biofilm formation of C. albicans at subinhibitory concentrations. Complex 4 also successfully prevented the adhesion of C. albicans in an in vitro epithelial cell model. The mechanism of the antifungal activity of copper(ii) complexes 1-5 was studied through their interaction with ct-DNA, as one of the possible target biomolecules, by fluorescence spectroscopy and gel electrophoresis. Finally, the ability of these complexes to bind to bovine serum albumin (BSA) was studied by fluorescence emission spectroscopy.

In order to develop a novel antifungal agent, we synthesized and completely structurally characterized the silver(I) complex with the known antimycotic itraconazole (itraco), [Ag(itraco-N)(2)]NO3 center dot H2O (Agitraco). The spectroscopic and crystallographic results revealed that, in this complex, two itraco ligands are monodentately coordinated to the Ag(I) ion via the triazole nitrogen atom forming a cationic [Ag(itraco-N)(2)]+ part, which is neutralized by the nitrate anion. The antifungal effect of silver(I) complex and itraconazole was evaluated against four different Candida species (C. albicans, C. glabrata, C. parapsilosis and C. krusei) by means of minimal inhibitory concentrations (MICs). Agitraco complex shows enhanced antifungal activity than itraco, being 2.3- and 4.5-fold more active against C. albicans and C. glabrata, respectively. The complex was also more efficient in inhibiting yeast to hyphae transition process in C. albicans, which is an important step in its pathogenesis. Part of the improved activity of Agitraco could be attributed to the greater induction of reactive oxygen species in Candida spp. with respect to itraco. The toxicity evaluation in the zebrafish model (Danio rerio) suggests that the Agitraco complex has better therapeutic profile and improved antifungal efficacy with respect to the parent drug, which were also proven in vivo using the zebrafish model of lethal disseminated candidiasis. Interaction of Agitraco with bovine serum albumin (BSA) was investigated with the aim to assess its binding affinity toward this biomolecule.