Infrared and Thermal Analysis of Vanadyl(II) Barbiturate Complex

An usual method for the preparation of vanadyl(II) barbiturate complex was performed under the chemical reaction of vanadyl(II) sulfate with barbituric acid (H2L) and formulated as: [VO(HL)2].2H2O. This new barbiturate complex was synthesis and characterized by elemental analysis, molar conductivity, magnetic measurements, infrared spectral method and simultaneous thermal analysis (TG/DTG) techniques. The molar conductance measurements proved that barbiturate vanadyl(II) complex is non-electrolytes. The infrared spectra of the barbituric and vanadyl(II) complex are used to identify the mode of coordination. Kinetic and thermodynamic parameters (E*, ΔH*, ΔS* and ΔG*) of H2L ligand and its complex are estimated according to the DTG curves.Â

Biogenic volatile compounds of activated sludge and their application for metal bioremediation

Heavy metals pollution is nowadays one of the most important environmental concerns. This paper illustrates the employment of the biogenic volatile compounds generated during the aerobic growth of activated sludge on raw domestic wastewater for heavy metals removal. Most of the tested metals even as individual or mixed metal species (Co, Cu, Cd, Fe, Hg, Ni, Mn, Pb and Zn) were potentially transformed into insoluble precipitates and then separated out of their solutions. The Fourier-transform infrared (FTIR) analysis has identified some organosulfur groups (thiol, disulfide and thiocarbonyl), in addition to amine group in the metal precipitates. This study highlighted the application of the microbial volatile metabolites for heavy metals bioremediation in a powerful, cost effective and eco-friendly bioprocess.Key words: Application, activated sludge, biogas, metals, bio-precipitatio

In situ acetonitrile/water mixed solvents: An ecofriendly synthesis and structure Explanations of Cu(II), Co(II), and Ni(II) complexes of thioxoimidazolidine

ABSTRACT. The bidentate oxoacetate derivative of 4-oxo-2-thiazolidine 4ligand (L1) synthesized by the reaction of 1-(1-(Pyridin-3-yl)ethylideneamino)-2-thioxoimidazolidin-4-one 3 with diethyl oxalate with both traditional and microwave irradiation methods. The metal ion complexes of mixed ligands L1 and L2 (acetonitrile) were prepared by condensation a solution mixture of Co(II) Ni(II), and Cu(ІІ) metal chloride salts with the ligands (L1 and L2) in distilled water with stirring. The complexes were characterized by the micro analysis (C, H, N), chloride content, FT-IR, UV-Vis spectra, thermal gravimetric analysis (TGA), molar conductivity as well as magnetic susceptibility measurement. According to the obtained data the suggested coordination geometries of these complexes were suggested as octahedral structure. All the synthesized complexes were found to be electrolyte due to the presence of chloride ions outside the coordination sphere. The antibacterial activity of the L1 ligand and their metal ion complexes have been studied by screening against various microorganisms, G+ bacteria (Bacillus subtillis, Streptococcus pneumonia, and Staphyloccoccus aurease), G-bacteria (E. coli, and Pesudomonas Sp.) and fungi (Aspergillus nigaer, and Penicillium Sp.). The metal ion complexes gave the formulae: [M(L1)(L2)2(H2O)2]Cl2where M = Co(II) Ni(II), and Cu(ІІ).                     KEY WORDS: Imidazolidine, Microwave irradiation, Transition metals complexes, Biological activity   Bull. Chem. Soc. Ethiop. 2021, 35(2), 351-364. DOI: https://dx.doi.org/10.4314/bcse.v35i2.1

Solvent free synthesis of hydrazine carbothioamide derivatives as a precursor in the preparation of new mononuclear Mn(II), Cu(II), and Zn(II) complexes: Spectroscopic characterizations

ABSTRACT. Over the last few years considerable attention has been devoted to the study of Schiff base complexes of metal(II) containing nitrogen, oxygen and sulfur donor ligands due to their diverse biological activities. Therefore, the Schiff base thiosemicarbazone derivatives of 2-(2-hydroxy-3-methoxybenzylidene) hydrazine carbothioamide (HL1) and 2-(4-bromo-2-hydroxy-3-methoxybenzylidene) hydrazine carbothioamide (HL2) were synthesized with solvent free technique using silica gel as material support for the reaction. The structures of the precursor’s organic products confirmed with their 1H, 13C NMR, IR and microanalysis data. Six new manganese(II), copper(II), and zinc(II) complexes of HL1 and HL2 2-(2-hydroxy-3-methoxybenzylidene) hydrazinecarbothioamide derivatives with the general formulation [ML1Cl] and [ML2Cl], where M = Mn2+, Cu2+, and Zn2+ were prepared and well discussed by using elemental analyses, magnetic moments, molar conductance, infrared and electronic spectral techniques. The assignments data of spectroscopic analysis confirm that the synthesized thiosemicarbazone Schiff bases of acts as a tridentate ligand as sulfur-oxygen-nitrogen donating atoms. The values of magnetic moments agreed with the data of electronic spectra which both suggested a four-coordination geometry of the synthesized complexes.                     KEY WORDS: Schiff base, Thiosemicarbazone, Manganese(II) complex, Copper(II) complex, Zinc(II) complex   Bull. Chem. Soc. Ethiop. 2021, 35(2), 413-424. DOI: https://dx.doi.org/10.4314/bcse.v35i2.1

Spectrophotometric and Thermal Studies of the Reaction of Iodine with Nickel(II) Acetylacetonate

The reaction of iodine (acceptor) and nickel(II) acetylacetonate (donor) was studied photometrically in different solvents such as chloroform, dichloromethane and carbon tetrachloride at room temperature. The results indicate the formation of a 1: 1 charge-transfer complex in each solvent and the iodine complex is formulated as the triiodide species [Ni(acac)2]2I+.I3-, based on the characteristic electronic absorptions of the I3- ion at 361 and 285 nm, as well as on the far infrared absorption bands characteristic of the I3- ion with C2v symmetry. These bands are observed at 132, 101 and 84 cm-1 and are assigned to na(I-I), ns(I-I) and d(I3-), respectively. The values of the equilibrium constant (K), absorptivity (e) and oscillator strength (f) of the iodine complex are shown to be strongly dependent on the type of solvent used. The important role played by the solvent is suggested to be mainly due to the interaction of the ionic complex with the solvent. The proposed structure of the new solid triiodide charge-transfer complex reported in this study is further supported by thermal and mid-infrared measurements. (South African Journal of Chemistry: 2003 56: 10-14

Preparation, spectroscopic, thermal and molecular docking studies of covid-19 protease on the manganese(II), iron(III), chromium(III) and cobalt(II) creatinine complexes

ABSTRACT. Creatinine biomolecule has three different coordination modes through the (exocyclic O(5) and ring N(1)), (imine N(2) and ring N(1)) or as monodentate ligand via exocyclic O(1)). The FTIR and electronic spectra of the synthesized manganese(II), iron(III), chromium(III), and cobalt(II) complexes consistent with the coordinated behavioral derived from the structural analyses. Thermogravimetric data agree with the stoichiometry and proposed formulas [Mn(C4H7N3O)2(Cl)2]4H2O, [Fe(C4H7N3O)2(Cl)2]Cl.6H2O, [Cr(C4H7N3O)2(Cl)2]Cl.6H2O, and [Co(C4H7N3O)2(Cl)2]6H2O. Four new transition metal complexes derived from the reaction of creatinine chelate and metal salt (MnCl2.4H2O, FeCl3.6H2O, CrCl3.6H2O, and CoCl2.6H2O), were prepared with 1:2 (metal: ligand) stoichiometry, isolated and well characterized by a different spectral and analytical techniques including FTIR, UV/Vis, magnetic susceptibility, molar conductance, elemental analysis, and TGA/DrTGA/DTA. The solid complexes were formed with the binding of the creatinine ligand through exocyclic O(5) and ring N(1) and presented as an octahedral geometry. In addition molecular docking calculations have been performed between complexes of manganese(II), iron(III), chromium(III) and cobalt(II) with creatinine biomolecule ligand with the Covid-19 protease (6LU7) to determine the best binding site and its inhibitory effect.                     KEY WORDS: Creatinine, Coordination, Transition metals, TGA/DTA, Octahedral geometry   Bull. Chem. Soc. Ethiop. 2021, 35(2), 399-412. DOI: https://dx.doi.org/10.4314/bcse.v35i2.1

Synthesis, characterization, thermal analysis and biological study of new thiophene derivative containing o-aminobenzoic acid ligand and its Mn(II), Cu(II) and Co(II) metal complexes

New ligand containing 2-(2,4-dioxo-4-thiophen-2-yl-butyrylamino)-benzoic acid (HL) merged moiety was synthesized and characterized by FT-IR, elemental analyses, mass spectra and 1H-NMR spectral. In the present study, the attempts were carried to form complexes of HL ligand with some transition metal ions (MnII, CuII and CoII) of well-defined at the (1:1) ratio of the components in the dimethyl sulfoxide (DMSO) solvent. All complexes have been studied by FTIR spectra, elemental analyses, thermal analysis, molar conductivity, electronic spectra and magnetic moment. The HL ligand produced as a bidentate chelate with interactive metal ions. All the results suggested octahedral geometry to complexes and have the formulae [M(HL)(Cl)2(H2O)2].nH2O where M = Mn(II), Cu(II) and Co(II). The IR spectra of the complexes were assigned and compared with the data in literature. The kinetic and thermodynamic results such as E*, ΔH*, ΔS* and ΔG* were calculated based o the TGA/DTG curves using Coats and Redfern and Horowitz and Metzger approximation methods. Furthermore, the resultant complexes were evaluated for the anti-bacterial and anti-fungal potential.                     KEY WORDS: 2-(2,4-Dioxo-4-thiophen-2-yl-butyrylamino)-benzoic acid, Transition metal complexes, FTIR, TGA, Antimicrobial test   Bull. Chem. Soc. Ethiop. 2021, 35(1), 129-140. DOI: https://dx.doi.org/10.4314/bcse.v35i1.1

Clinical audit of neonatal care in Assiut Women's Health Hospital, Egypt

Background: The current study aims to auditing the current care of healthy full term newborns in the delivery room and identify the gap between the current practice and ideal practice in Assiut Women's Health Hospital, Egypt.Methods: The current study was a clinical audit carried out in Assiut Woman Health Hospital, in the period from 1 September 2016 to 28 February 2017.The study included all newborns delivered in the delivery word of gestational age after 37 week. We excluded all Preterm babies, those with congenital anomalies, pregnant women with medical disorders and multiple pregnancies. In the present work all data was collected prospectively through direct personal patient contact, direct observation of care givers, patient interactions and attitudes, from the clinical records and then recording the data in special check sheet. All basic criteria of the study participants as age, parity, gestational age at delivery and type of delivery were obtained. The neonatal gender, weight, heart rate and respiratory rate were checked. Audit criteria were selected according to the WHO 2015 and AAP 2010-2015 guidelines.Results: The study included 800 women; the mean age of the women was 26.52±5.70 years. The mean parity was 1.78±1.85. The mean gestational age at delivery was 38.81±0.96 weeks. As regard the type of delivery, 54.1% of women were delivered by cesarean section. Calling neonatologists occurred in 67.9% of deliveries. The mean birth weight was 3.17±0.39 kilograms. Nearly half of them (52%) were males.Conclusions: Application of the guidelines of the neonatal handling is important for optimum care to the neonates. Re-audit the steps of the handling is important to discuss whether practice has improved or not in our tertiary hospital

Synthesis, characterization, and photocatalytic efficiency of a new smart PdO oxide nanomaterials for using in the recycling and sustainable wastewater treatment

Nanostructured PdO materials with promising catalytic properties were successfully synthesized by the controlled thermal decomposition in air of three Pd(II) complexes containing Pd(II) ion, ofloxacin drug and amino acid. The Pd(II) complexes which were used as precursors were [Pd(OFL)(Gly)]Cl, [Pd(OFL)(Ala)]Cl, and [Pd(OFL)2]Cl2, where Gly is glycine amino acid, Ala is alanine amino acid, and OFL is ofloxacin. Structural and morphological properties of the synthesized PdO materials were obtained using FTIR, XRD, SEM, and EDX techniques. The XRD results confirm the tetragonal structure of PdO. The obtained PdO materials were tested as a catalyst for the heterogeneous degradation of H2O2 solution. The results revealed that PdO could effectively degrade H2O2.                     KEY WORDS: PdO, Nanoparticles, Photocatalytic efficiency, Wastewater treatment   Bull. Chem. Soc. Ethiop. 2021, 35(1), 107-118. DOI: https://dx.doi.org/10.4314/bcse.v35i1.