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European Journal of Chemistry, Volume 12, pp 1-12; doi:10.5155/eurjchem.12.1.1-12.2031

Abstract:
A new spectrofluorimetric reagent N-(pyridin-2-yl)-quinoline-2-carbothioamide (PQTA) has been synthesized and characterized. A very simple, ultra-sensitive, and highly selective, and non-extractive new spectrofluorimetric method for the determination of molybdenum at pico-trace levels using PQTA has been developed. This novel fluorimetric reagent PQTA, becomes oxidized in a slightly acidic (0.0025-0.05 M H2SO4) solution with molybdenum (VI) in absolute ethanol to produce a highly fluorescent oxidized product (λex = 300 nm; λem= 377 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.0025-0.0500 M H2SO4) for the period between 2 min and 24 h. Linear calibration graphs were obtained for 0.001-600 μg/L of Mo having a detection limit of 0.15 ng/L; the quantification limit of the reaction system was found to be 1.5 ng/L and the RSD was 0-2%. A large excess of over 60 cations, anions, and complexing agents like chloride, phosphate, azide, tartrate, oxalate, and SCN- etc. do not interfere in the determination. The developed method was successfully used in the determination of molybdenum in several Certified Reference Materials (Alloys, steel, serum, bovine liver, drinking water, soil, and sediments) as well as in some environmental waters (Potable and polluted), biological fluids (Human blood, urine, hair, and milk), soil samples and food samples (Vegetables, rice, and wheat) solutions containing both molybdenum (VI) and molybdenum (V) ions. The results of the proposed method for assessing biological, food and vegetable samples were comparable with ICP-OES and AAS were found to be in excellent agreement.
European Journal of Chemistry, Volume 12; doi:10.5155/eurjchem.12.1.iii-vi.2112

European Journal of Chemistry, Volume 12, pp 52-55; doi:10.5155/eurjchem.12.1.52-55.2077

Abstract:
Since street drugs are frequently and rapidly modified, in order to circumvent the current laws that make them illicit, it is necessary to fully identify them by single crystal X-ray diffraction; subsequently, ideal powder patterns are computed for rapid identification of additional confiscations, which are mostly available in powder form. Monoacetyl morphine is found in samples of heroin as a by-product of incomplete synthesis, or from degradation of diacetyl morphine caused by heat, humidity, or pH changes. It is formed by the hydrolysis of the acetyl function on the benzene moiety of the morphine ring, thereby inserting an OH moiety at that site. This compound, 6-monoacetyl morphine, is the primary and active metabolite of heroin, rapidly hydrolyzed in the user’s blood. Herein, we describe the structure of 6-monoacetyl morphine, IUPAC name: [(4R,4aR,7S,7aR,12bS)-9-hydroxy-3-methyl-2,4,4a,7,7a,13-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-7-yl] acetate (A), as the trihydrated hydrochloride, whose structure has not been described previously. Our crystals belong in space group P212121 with cell parameters of a = 6.9367(2), b = 13.0374(3), c = 21.9856(6) Å, V = 1988.30 (9) Å3; its composition is C19H22NO4Cl·3H2O, and Z = 4.0. A full sphere of data was collected at 100 K using CuKα radiation (λ = 1.54178 Å), yielding 3594 unique reflections measured and a final R-factor = 4.1%, with a Flack parameter = 0.05(1).
European Journal of Chemistry, Volume 12; doi:10.5155/eurjchem.12.1.i-ii.2111

, Rayan Saud Al-Arifi, Abdulaziz Abdullah Al-Qarni, , Fahad Ibrahim Al-Jenoobi
European Journal of Chemistry, Volume 12, pp 18-22; doi:10.5155/eurjchem.12.1.18-22.2036

Abstract:
A rapid UPLC-ESI-MS method was developed for simultaneous determination of caffeine and taurine in beverages (energy drinks and soft drinks). The molecular ions of caffeine and taurine were identified in single ion recording mode at m/z 194.98 and 125.86, respectively. The mass spectrometer parameters were optimized as: capillary voltage 3.0 kV, cone voltage 35 V, extractor 3 V, RF Lens 0.1 V, source temperature 150 °C, desolvation temperature 350 °C, nitrogen 600 L/h, LMR1 7.9, HMR1 15.2, IE1 0.30. The mobile phase comprising methanol (0.1% formic acid) (A) and water (5 mM ammonium acetate) (B) was used in gradient mode. The mobile phase components A and B were pumped in 80:20 (v:v) ratio from 0-0.44 min, and then 100% of component A was pumped between 0.45-0.68 min, and at 0.69 min the composition was returned to 80:20 (v:v) ratio of A and B till 2.0 min. Caffeine and taurine were eluted at 0.46 and 0.43 min, respectively. The samples of energy drinks and soft drinks were diluted in a solvent system comprising methanol and water in 80:20 (v:v) ratio. Our investigations showed that soft drinks SD1 and SD2 have 88.8±4.2% and 110.7±3.6% (w:w) caffeine of their labeled claim. The caffeine content in energy drink brands ED1, ED2, ED3, and ED4 was 76.9±2.5, 65.6±3.4, 88.1±12.6, and 89.1±2.8% (w:w) of labeled claims, respectively. While taurine content in ED1, ED2, ED3, and ED4 was 86.5±8.4, 81.3±27.5, 101.9±4.8, and 97.1±0.3% (w:w) of labeled claim, respectively.
European Journal of Chemistry, Volume 12, pp 60-63; doi:10.5155/eurjchem.12.1.60-63.2089

Abstract:
The synthetic leucite silicate framework mineral analogues Cs2XSi5O12 (X = Cu, Cd, Zn) were prepared by high-temperature solid-state synthesis. The results of Rietveld refinement, using 18 keV synchrotron X-ray powder diffraction data collected at low temperatures (8K X = Cu, Zn; 10K X = Cd) show that the title compounds crystallize in the space group Pbca and are isostructural with the ambient temperature structures of these analogues. The structures consist of tetrahedrally coordinated SiO4 and XO4 sharing corners to form a partially substituted silicate framework. Extraframework Cs cations sit in channels in the framework. All atoms occupy the 8c general position for this space group. In these refined structures, silicon and X atoms are ordered onto separate tetrahedrally coordinated sites (T-sites).
, Muna Mahdi Mohammed, , Asha Fadllallah Wady, Awad Salim Ibrahim Holy
European Journal of Chemistry, Volume 12, pp 56-59; doi:10.5155/eurjchem.12.1.56-59.2070

Abstract:
Schiff bases are versatile ligands, synthesized via condensation of primary amines with carbonyl compounds. In this study, equimolar amounts of 4-imidazolecarboxaldehyde and thiosemicarbazide were combined and the Schiff base 4-imidazolecarboxaldehyde thiosemicarbazone was prepared as a new bidentate complexing agent. The synthesized ligand was reacted with palladium (II) and platinum (II) ions yielding air-stable complexes. For characterization purpose, infrared spectra, mass spectra, electronic spectra, thermal analysis, proton nuclear magnetic resonance and 13-carbon nuclear magnetic resonance spectra studies were carried out on the obtained complexes and ligand. The characterization data showed that the ligand acts as a bidentate coordinate to the metal ions through azomethine nitrogen and sulfur atoms. An in vitro antimicrobial investigation was also carried out for the free ligand and its metal complexes against four bacteria; Bacillus cereus, Staphylococcus aureus (Gram-positive), Escherichia coli and Salmonella typhimurium (Gram-negative) and one Fungi; Candida albicans, to assess their antimicrobial properties by disc diffusion technique. Antimicrobial activity of the prepared complexes showed higher activity than the free ligand.
European Journal of Chemistry, Volume 12, pp 32-36; doi:10.5155/eurjchem.12.1.32-36.2051

Abstract:
Senegal is affected by a relatively high prevalence of iodine deficiency disorders, which compromises its social and economic development. To address this situation, the Universal Salt Iodization strategy was adopted by the Senegalese Government. The monitoring of salt iodine status is crucial to the success of such a program. Therefore, this study aimed to evaluate the iodine concentration of table salt from Senegalese households. A total of 1575 samples collected in urban and rural areas were analyzed using the iodometric method. The powdered salt samples showed higher mean iodine content (18.99 ppm) and lower percentage of non-compliance (58.4%) than the other salt types (p = 0.02). Most of the samples collected from urban area were found with iodine content between 15 and 39.9 ppm, whereas, in rural areas, the situation was significantly different (p = 0.01). Iodine levels of most samples were lower than 5 ppm in the rural producing area or varied between 5 to 14.9 ppm in the rural non-producing area. A percentage of 37.3% of adequately iodized salt samples was obtained at a national scale with a significant disparity between urban and rural areas. Therefore, improvements in quality control procedures in tandem with the iodization process are necessary and an information, education and communication strategy should be adopted.
European Journal of Chemistry, Volume 12, pp 77-80; doi:10.5155/eurjchem.12.1.77-80.2068

Abstract:
Several studies have reported the presence of amine and imine tautomeric forms for hydrogenated 1,3-thiazine derivatives. However, identification of their tautomeric forms by UV, FTIR and mass-spectral methods does not yield expected results. Here, we report the synthesis of 2-phenylaminodihydro-1,3-thiazine and 2-phenyliminotetrahydro-1,3-thiazine and the analysis of their UV, FTIR and NMR (1H and 13C) spectral data. An identical picture of UV spectra was recorded for both compounds. However, distinctive characteristics were found in the FTIR, 1H and 13C NMR spectra. The C=N band of amine form was observed in higher frequency region relative to imine form. The signal of C2 carbon of amine form in 13C NMR spectrum was occurred in more downfield (δ 165.3 ppm) relative to C2 signal of imine form (δ 152.1 ppm). In addition, the difference between C2 and C8 carbon signals of amine form was very high (Δδ = 30.6 ppm) relative to imine form (δ 5.4 ppm). The position of C2 and C8 signals and the difference between them in 13C NMR spectrum was found to be more promising in identification of tautomeric forms in case of hydrogenated 1,3-thiazine derivatives.
Ibragimdjan Аbdugafurov Azizovich, Fazliddin Qirgizov Bakhtiyarovich, Ilhom Оrtikov Sobirovich
European Journal of Chemistry, Volume 12, pp 13-17; doi:10.5155/eurjchem.12.1.13-17.2035

Abstract:
The development of highly effective and low-toxicity nonsteroidal anti-inflammatory drugs (NSAIDs) is one of the important challenges facing modern pharmacology. To overcome this problem, many studies have been conducted on compounds containing a five-membered heterocycle containing three nitrogen atoms. The pharmacodynamics of these compounds are mainly due to their anti-inflammatory effect. Therefore, it is important to synthesize new derivatives of 1,2,3-triazoles, to determine their structure and to look for substances with anti-inflammatory activity on their basis. For the first time, the corresponding derivatives of 4-(4-(exchangeable)-1H-1,2,3-triazole-1-yl)-benzoic acid were synthesized by cycloaddition of propargyl esters of saturated carboxylic acids and para-azidobenzoic acid in the presence of copper (I) iodide. The structure of the obtained substances was analyzed by IR, 1H NMR, and MS techniques. It is proved that under the action of the catalyst in the reaction, only 1,4-isomers are formed. Factors affecting the course of the reaction were identified. Only one isomer is formed in the reaction of cyclic addition under the action of a catalyst and the effect of temperature, duration of time, and nature of the solvent on the reaction yield was studied.
Santhosha Sangapurada Mahantheshappa, HarishKumar Shivanna, Nayak Devappa Satyanarayan
European Journal of Chemistry, Volume 12, pp 37-44; doi:10.5155/eurjchem.12.1.37-44.2038

Abstract:
The synthesis, antimicrobial, and antioxidant activities of new quinoline analogs were carried out with the aim to find possible hits/leads that can be taken up for future drug development. A series of 2-amino-N’-((2-chloroquinolin-3-yl)methylene)acetohydrazide derivatives (6a-h) have been synthesized by reacting 2-chloro-N’-((2-chloroquinolin-3-yl)methylene)acetohydrazide (5a) and N’-((6-bromo-2-chloroquinolin-3-yl)methylene)-2-chloroacetohydrazide (5b) with secondary amines (Morpholine, diethylamine, piperidine and 1-methylpiperazine). The characterization was achieved by FT-IR, 1H NMR, 13C NMR, and mass spectral analysis. The in silico ADMET studies of the synthesized molecules were analyzed for their drug likeliness and toxic properties. The ADMET study indicates that the synthesized compounds were found to be possessing reliable ADME properties and are nontoxic. The antimicrobial properties were tested against bacterial and fungal species with amoxicillin and fluconazole as standard drugs. The compounds 6a, 6c, 6e, and 6g exhibited good antibacterial potency against P. aeruginosa, and the compounds 6a, 6f, and 6h have shown good activity against E. coli with 1000 µg/mL. The compounds 6b, 6c, and 6e have moderate activity against fungal species C. oxysporum and the compounds 6c, 6e, 6f, 6g, and 6h have good activity against P. chrysogenum. Synthesized compounds were also tested for the DPPH· free radical scavenging activity to check the antioxidant potential, and the results revealed that the compounds 6a, 6b, 6c, and 6e have exhibited antioxidant potency than the remaining synthesized derivatives. The possible hits generated from biological activity could be taken for the generation of lead molecules for the drug discovery of antimicrobial and antioxidant entities from quinoline.
European Journal of Chemistry, Volume 12, pp 23-31; doi:10.5155/eurjchem.12.1.23-31.2039

Abstract:
Three organophosphorus mercury (II) coordination compounds [Hg2(µ-X)2X2(PPh3)2] {X: I (1), Br (2), and Cl (3)} have been synthesized by the reaction of mercury (II) halides with triphenylphosphine. The prepared complexes were characterized by spectroscopic techniques as well as by elemental analysis. The crystal structure of [Hg2(µ-I)2I2(PPh3)2] (1) was obtained by single-crystal X-ray diffraction study. Crystal data for [Hg2(µ-I)2I2(PPh3)2], C36H30Hg2I4P2: Monoclinic, space group P21/c (no. 14), a = 19.2115(13) Å, b = 11.1291(8) Å, c = 19.0599(14) Å, β = 90.461(2)°, V = 4075.0(5) Å3, Z = 4, T = 293.15 K, μ (MoKα) = 10.657 mm-1, Dcalc = 2.336 g/cm3, 46095 reflections measured (4.23° ≤ 2Θ ≤ 49.994°), 7182 unique (Rint = 0.0563, Rsigma = 0.0365) which were used in all calculations. The final R1 was 0.0322 (I > 2σ(I)) and wR2 was 0.0780 (all data). The single crystal analysis of [Hg2(µ-I)2I2(PPh3)2] complex revealed that it has dimeric structure with bridged halides. [Hg2(µ-I)2I2(PPh3)2] complex has also a supramolecular arrangement through I···H-C interactions. The crystal packing and supramolecular features of these coordination compounds have also been studied using geometrical analysis, Hirshfeld surface analysis and DFT studies. Hirshfeld surface analysis indicated that H···H (49.3%), C···H (10.6%), and I···H (12.8%) interactions are the primary contributors to the intermolecular stabilization in the crystal. The equilibrium geometries of the studied complexes are investigated theoretically at the B3LYP/LANL2DZ level of theory. The calculated energy gap between HOMO-LUMO orbitals for complexes 1, 2, and 3 are in the trend of complex 3 > 2 > 1.
European Journal of Chemistry, Volume 12, pp 81-85; doi:10.5155/eurjchem.12.1.81-85.2107

Abstract:
The crystal structure of the sesquihydrate of dehydroepiandrosterone propan-2-ylidene hydrazone, [(7)2·(H2O)3], isolated from a solution of dehydroepiandrosterone propan-2-ylidene hydrazone, (7), in moist ethanol at room temperature, has been determined from data collected at 100 K. The sesquihydrate recrystallizes in the orthorhombic space group, P212121 with Z = 8. The asymmetric unit of [(7)2·(H2O)3] consists of two independent molecules of the steroid, Mol A and Mol B, and three moles of water. The six membered saturated rings, A and C, in both molecules have ideal or near ideal chair shapes, the unsaturated rings, B, have the expected half-chair shapes, while the five-membered rings, D, have envelope shapes with flaps at C114 and C214 for Mol A and Mol B, respectively. Differences in the conformations of the two molecules reside essentially completely within the hydrazonyl fragments with significantly different torsional angles, C117-N120-N121-C122 (in Mol A) and C217-N220-N221-C222 (in Mol B), of 149.19(14) and -93.08(17)°, respectively. The difference in this torsional angle is reflected in the hydrogen bonds involving the nitrogen atoms in the hydrazonyl units: it is of interest that the hydrazonyl nitrogen atoms partake as acceptors in hydrogen bonding with water molecules. The only intermolecular interactions in these molecules are hydrogen bonds -all classical O-H-O and OH···N hydrogen bonds with just one exception, a C-H···O(water) hydrogen bond. Of interest, there are no direct steroid-steroid links: molecules are linked solely by hydrogen bonds involving the hydrate molecules. All three hydrate molecules take part in the indirect linking of the steroid molecules, but each has its own set of contacts.
Fouzia Chang, , Huma Shaikh, , , Paras Aazadi Memon, Abdul Sattar Chang
European Journal of Chemistry, Volume 12, pp 45-51; doi:10.5155/eurjchem.12.1.45-51.2056

Abstract:
Metal-organic frameworks (MOFs)/coordination polymers (CPs) are a new class of hybrid inorganic/organic porous material. Recently MOFs have attracted much attention due to their large surface area, tunable pore structure, and high thermal stability. MOF-5 is composed of zinc salt and 1,4 benzene dicarboxylic linker. In the current study, MOF-5/cryogel composite was applied to extract cholesterol selectively from milk samples. This extraction process was used to clean-up milk samples with MOF-5/cryogel composite followed by determination of cholesterol in milk using UV-Vis spectrophotometric technique. The parameters such as concentration of cholesterol, volume of cholesterol solution, adsorbent amount, adsorption and desorption time were studied to obtain good extraction of cholesterol. The amount of cholesterol adsorbed and desorbed was 84 and 80%, respectively, from milk samples using MOF-5 composite cryogel. The developed method was validated in terms of linearity, accuracy, precision, limit of detection, and quantification. The response was linear in the range of 5-200 µg/mL with a coefficient of determination (r2) of 0.990. Detection limit (0.15 µg/mL) and quantification (0.45 µg/mL) were obtained.
European Journal of Chemistry, Volume 12, pp 64-68; doi:10.5155/eurjchem.12.1.64-68.2059

Abstract:
This study aimed to use microwave irradiation as a green technique, not only to enhance the dyeing efficiency of disperse-colored polyester fabrics, but also to conserve resources and minimize the environmental effects. Arylazopyrazolopyrimidinones dyes 1-9 were applied to polyester fabrics at 2% shade using conventional method and microwave at 100 °C. Both the color intensity expressed as dye absorption and the fastness characteristics of the dyed fabric were investigated. The K/S values are increased by increasing the time of irradiation from 10-60 minutes. The dyed substrate displayed good light fastness, and very good fastness levels to rubbing, perspiration washing, and sublimation, respectively.
European Journal of Chemistry, Volume 12, pp 86-108; doi:10.5155/eurjchem.12.1.86-108.2060

Abstract:
Currently, the size and shape selective synthesis of nanoparticles (NPs) and their varied catalytic applications are gaining significant enthusiasm in the field of nanochemistry. Homogeneous catalysis is crucial due to its inherent benefits like high selectivity and mild reaction conditions. Nevertheless, it endures with serious disadvantages of catalysts and/or product separation/recycles compared to their heterogeneous counterparts restricting their catalytic applications. The utilization of catalysts in the form of nano-size is an elective methodology for the combination of merits of homogeneous and heterogeneous catalysis. Magnesium oxide (MgO) NPs are important as they find applications for catalysis, organic transformation, and synthesis of fine chemicals and organic intermediates. The applications of MgO NPs in diverse organic transformations including oxidation, reduction, epoxidation, condensation, and C-C, C-N, C-O, C-S bond formation in a variety of notable heterocyclic reactions are also discussed. The use of MgO NPs in organic transformation is advantageous as it mitigates the use of ligands; the procurable separation of catalyst for recyclability makes the protocol heterogeneous and monetary. MgO NPs gave efficacious catalytic performance towards the desired products due to high surface area. By considering these efficient merits, scientists have focused their attentions towards stupendous applications of MgO NPs in selective organic transformation. In the current review article, we summarized the synthesis of MgO NPs and numerous characterization techniques, whereas the application section illustrates their utility as a catalyst in several organic transformations. We believe this decisive appraisal will provide imperative details to further advance the application of MgO NPs in selective catalysis.
, Prabhuswamy Akhileshwari, Mandayam Anandalwar Sridhar, , Shivegowda Nagaraju, ,
European Journal of Chemistry, Volume 12, pp 69-76; doi:10.5155/eurjchem.12.1.69-76.2067

Abstract:
Chalcones are the main component of some natural compounds. The title compound, 3-(2,5-dimethoxyphenyl)-1-(naphthalen-2-yl)prop-2-en-1-one, was synthesized and characterized. The compound (C21H18O3) crystallizes in the triclinic system with the space group of P-1 (no. 2), a = 7.7705(4) Å, b = 10.2634(6) Å, c = 11.2487(6) Å, α = 79.655(5)°, β = 81.500(5)°, γ = 68.039(5)°, V = 815.28(9) Å3, Z = 2, T = 293(2) K, μ(MoKα) = 0.086 mm-1, Dcalc = 1.297 g/cm3, 9126 reflections measured (4.318° ≤ 2Θ ≤ 52.728°), 3302 unique (Rint = 0.0466, Rsigma = 0.0528) which were used in all calculations. The final R1 was 0.0568 (I > 2σ(I)) and wR2 was 0.1667 (all data). The crystal structure is stabilized by both short C-H···O inter- and intra-molecular interactions. In addition, the crystal structure is reinforced by π-π interactions. Hirshfeld surface analysis confirmed the presence of C-H···O intermolecular interactions. The two-dimensional fingerprint plots are used to visualize the individual interactions present in the molecule. DFT calculations were performed to know the energy levels of the frontier molecular orbitals (HOMO-LUMO). The energy gap between the frontier molecular orbitals shows the kinetic stability of the molecule. The chemical reactive sites are observed by generating MEP surface. Non-covalent interactions (NCIs) are analyzed using reduced density gradient (RDG) analysis.
European Journal of Chemistry, Volume 11, pp 291-297; doi:10.5155/eurjchem.11.4.291-297.2002

Abstract:
A simple, sensitive and reproducible method for the determination of ranitidine hydrochloride in pharmaceutical preparations was investigated. This spectrophotometric method was based on the formation of a deep red color product with ninhydrin in basic media and the absorbance measured at λmax = 480 nm. The reaction occurs at 45 °C with pH = 10 having a contact time of 38 minutes. Under the optimum conditions, Beer’s Law is obeyed in the concentration range of 8.98×103 - 9.90×104 µg/L. The coefficient of correlation was found to be 0.999 for the obtained method with molar absorptivity of 3.05×103 L/mol.cm. The calculated Sandell’s sensitivity is 0.108 μg/cm2. The limit of detection and limit of quantification are 0.0997 and 0.3023 µg/mL, respectively. The low values of the percentage relative standard deviation and percentage relative error indicate the high precision and the good accuracy of the proposed method. The stoichiometry of the reaction is determined and found to be 1:4 (Ranitidine hydrochloride:Ninhydrin). The initial rate method confirmed that this reaction is first order one.
European Journal of Chemistry, Volume 11, pp 276-279; doi:10.5155/eurjchem.11.4.276-279.2009

Abstract:
A simple and eloquent procedure for the synthesis of a new series of thienyl benzo[b]1,4-diazepines is reported. They were synthesized by the condensation of o-phenylenediamine (o-PDA) with distinct hetero chalcones using NaOH in polyethylene glycol (PEG-400) as green and alternative reaction solvent. The significances of this present method are shorter reaction time, easy work-up, high yields, and mild reaction conditions. Furthermore, this method is environment friendly and without use of an expensive catalyst. The all newly synthesized compounds are characterized by the spectroscopic methods.
European Journal of Chemistry, Volume 11, pp 377-384; doi:10.5155/eurjchem.11.4.377-384.2040

Abstract:
Palladium complexes of sulfonyl hydrazone based ligands have been prepared by refluxing with the corresponding ligands and Pd(II) salt in 2:1 ratio. The compounds have been characterized by FT-IR and UV-Vis spectroscopic methods. The crystal structure of the prepared palladium complexes has been determined by single-crystal X-ray crystallographic technique. Crystal data for C40H50N4O6PdS2 (PMHT-Pd(II) complex): triclinic, space group P-1 (no. 2), a = 7.1561(6) Å, b = 12.1300(11) Å, c = 12.6117(17) Å, α = 63.498(11)°, β = 86.694(9)°, γ = 81.451(7)° and Z = 1. The final R1 was 0.0699 (I > 2σ(I)) and wR2 was 0.1834 (all data). Crystal data for C36H42N4O6PdS2 (PTHC-Pd(II) complex): monoclinic, space group P21/n (no. 14), a = 8.6726(2) Å, b = 20.8824(4) Å, c = 10.3351(2) Å, β = 104.429(2)° and Z = 2. The final R1 was 0.0344 (I > 2σ(I)) and wR2 was 0.0840 (all data). Crystal data for C36H42N4O6PdS2 (PTHT-Pd(II) complex): monoclinic, space group P21/n (no. 14), a = 9.7658(2) Å, b = 10.0488(3) Å, c = 18.7714(4) Å, β = 99.602(2)° and Z = 2. The final R1 was 0.0334 (I > 2σ(I)) and wR2 was 0.0832 (all data). Crystal data for C40H50N4O6PdS2 (PMHC-Pd(II) complex): triclinic, space group P-1 (no. 2), a = 10.2070(9) Å, b = 12.1841(13) Å, c = 16.8879(19) Å, α = 109.005(6)°, β = 90.061(5)°, γ = 99.032(5)° and Z = 2. The final R1 was 0.0822 (I > 2σ(I)) and wR2 was 0.2293 (all data). The single-crystal structure data showed a good agreement with the experimental results. The synthesized complexes were screened for their in vitro antibacterial activity against one Gram-negative (Escherichia coli) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains and for in vitro antifungal activity against Aspergillus niger, Aspergillus flavus and Aspergillus fumigatus. The PTHC-Pd(II) complex possesses the nearby significant antifungal activity analogous to the standard drug fluconazole against selected fungal strains Aspergillus niger, Aspergillus Flavus and Aspergillus fumigatus as well as the same complex showed the antibacterial activity for Staphylococcus aureus as comparable to standard ofloxacin drug.
European Journal of Chemistry, Volume 11, pp 304-313; doi:10.5155/eurjchem.11.4.304-313.2033

Abstract:
A green synthetic route leading to the discovery of a series of diversely substituted pyrazolo[1,5-a]pyrimidines, having CO2Et group embedded at position-2 has been unraveled in this article. A series of formylated active proton compounds that were chosen to react with a carboxylate substituted-3-aminopyrazole under ultrasonic irradiation in the presence of a mild acid as a catalyst and aqueous ethanol medium afforded the desired products. The molecular structures of all these synthesized compounds were established by their spectral and analytical data. A model molecule 3d, subjected to single-crystal X-ray crystallography analysis further confirms their molecular structure. The crystal crystallized to a monoclinic cell with P21/c space group, a = 7.468 (5) Å, b = 27.908 (17) Å, c = 7.232 (4) Å, β = 104.291 (7)o, V =1460.7(15) Å3, Z = 4, μ(MoKα) = 0.096 mm-1, Dcalc = 1.352 Mg/m3 16667 measured reflection (5.63 ≤ 2Θ ≤ 57.57°), 3720 unique (Rint = 0.0965, Rsigma = 0.0945) which were used in all calculations. The final R1 was 0.0750 (I > 2σ(I)) and wR2 was 0.2226 (all data). These compounds were further explored for their antibacterial potential, and a few of them have exhibited encouraging results.
European Journal of Chemistry, Volume 11, pp 319-323; doi:10.5155/eurjchem.11.4.319-323.2047

Abstract:
Herein, we describe the synthesis and characterization of bis(N-(diethylcarbamothioyl)cyclohexane carboxamido)copper(II) complex, cis-[Cu(L-κ2S,O)2], has been prepared by the reaction of N-(diethyl carbamothioyl)cyclohexanecarboxamide ligand with copper(II) acetate. The green colored crystals of the complex were obtained by slow evaporation of their dichloromethane:ethanol solution (2:1, v:v). The crystal structure of cis-[Cu(L-κ2S,O)2] was obtained by single-crystal X-ray diffraction. The crystal structure reveals an monoclinic C2 (no. 5) space group with cell parameters a = 14.848(3) Å, b = 10.543(2) Å, c = 10.511(2) Å, β = 123.84(3)°, V = 1366.7(7) Å3, Z = 2, T = 153(2) K, μ(MoKα) = 0.979 mm-1, Dcalc = 1.327 g/cm3, 4979 reflections measured (6.6° ≤ 2Θ ≤ 50.68°), 2243 unique (Rint = 0.0223, Rsigma = 0.0444) which were used in all calculations. The final R1 was 0.0225 (>2sigma(I)) and wR2 was 0.0490 (all data). The angular structural index parameter, τ4, is equal to 0.40, which confirms the distorted square planar geometry for the title compound. The puckering parameters (q2 = 0.015(3) Å, q3 = 0.576(3) Å, QT = 0.577(3) Å, θ = 1.6(3)° and φ = 20(11)°) of the title complex show that the cyclohexane ring adopts a chair conformation. The two ethyl groups of the diethyl amine group have anti-orientation with respect to one another. The crystal packing shows the molecules stacked in parallel sheets along [010], accompanied by C3-H3A···O1ⁱ (i -x, +y, 1-z) intermolecular contact.
European Journal of Chemistry, Volume 11, pp 298-303; doi:10.5155/eurjchem.11.4.298-303.2032

Abstract:
In this work, two types of azobenzene derivatives based on Disperse Yellow 7 (DY7, 4-[4-(phenylazo)phenylazo]-o-cresol) were synthesized, which are bis-azobenzenes bearing flexible functional 6-bromohexyl chain or carboxylic acid moiety. The first one was synthesized by alkylation of DY7 with an excess of 1,6-dibromohexane in the presence of a mild base (K2CO3). The second one (azo dye with carboxylic acid functionality) was obtained by the alkaline hydrolysis of the ester bond of the newly obtained DY7 derivative with the ethoxycarbonyl group. The synthesized compounds were characterized by different spectral analytical techniques such as 1H NMR, 13C NMR, FT-IR, and UV-Vis. They can be employed for the synthesis of a wide variety of azo-based materials, which may be suitable for photochromic systems and molecular electronics applications.
European Journal of Chemistry, Volume 11, pp 324-333; doi:10.5155/eurjchem.11.4.324-333.2028

Abstract:
A combined theoretical and experimental investigation on a pharmaceutically important binary complex 3,3'-[(3-benzimidazolyl)methylene]bis(4-hydroxy-2H-1-benzopyran-2-one): 5-methyl-1,3-thiazol-2(3H)-imine is presented in this manuscript. The compound crystallizes in the monoclinic crystal system with space group Cc with unit cell parameters: a = 19.8151(8) Å, b = 15.2804(6) Å, c = 8.3950(4) Å, β = 94.0990(10)°, V = 2535.36(19) Å3, Z = 4, T = 296(2) K, μ(MoKα) = 0.184 mm-1, Dcalc = 1.490 g/cm3, 35833 reflections measured (5.332° ≤ 2Θ ≤ 56.678°), 6168 unique (Rint = 0.0467, Rsigma = 0.0388) which were used in all calculations. The final R1 was 0.0435 (I > 2σ(I)) and wR2 was 0.1073 (all data). The crystal structure has been determined by the conventional X-ray diffraction method, solved by direct methods and refined by the full matrix least squares procedure. Intramolecular hydrogen bonding of the type C–H⋅⋅⋅O and O–H⋅⋅⋅O is present and the crystal structure stabilizes via N–H…O, C–H…N and O–H…N intermolecular interactions. The optimized structural parameters have been compared and the parameters like ionization potential, electron affinity, global hardness, electron chemical potential, electronegativity, and global electrophilicity based on HOMO and LUMO energy values were calculated at B3LYP/6-311G(d,p) level of theory for a better understanding of the structural properties of the binary complex.
European Journal of Chemistry, Volume 11, pp 334-341; doi:10.5155/eurjchem.11.4.334-341.2037

Abstract:
Three new halide bridged copper(I)complexes [Cu2(µ-L)(µ-X)2)(PPh3)2]n {X: I (1), Br (2) and Cl (3)} have been synthesized by the reaction of Cu(I)X (X: I, Br and Cl) with PPh3 and the polydentate imino-pyridyl ligand L. Interestingly, copper(I) forms coordination polymers with the ligand L and the co-ligand PPh3. These complexes 1, 2 and 3 have been characterized by elemental analysis, IR, UV-Vis, and NMR spectroscopy. The crystal structure of the complex 2 has been determined by single-crystal X-ray analysis. Crystal data for complex 2: triclinic, space group P-1 (no. 2), a = 9.471(10) Å, b = 11.043(11) Å, c = 13.215(18) Å, α = 65.853(18)°, β = 69.94(2)°, γ = 67.350(14)°, V = 1135(2) Å3, Z = 2, T = 296.15 K, μ(MoKα) = 2.806 mm-1, Dcalc = 1.535 g/cm3, 4059 reflections measured (3.462° ≤ 2Θ ≤ 44.818°), 2639 unique (Rint = 0.0637, Rsigma = 0.1621) which were used in all calculations. The final R1 was 0.0700 (I > 2σ(I)) and wR2 was 0.2207 (all data). Hirshfeld surface analysis of the complex 2 showed H···H, N···H and Br···H interactions of 55.9, 14.4 and 4.1%, respectively. MEP of ligand L reflects the whole molecule is reddish yellow in color because of equally distributed electron density over the molecule. For this reason, the ligand is supramolecularly arranged via -{CuI2-µ-X2} rhomboid core in the complex 2. The ligand L is non-emissive at room temperature in dichloromethane, whereas the complexes 1, 2 and 3 are photoluminescent. DFT and Hirshfeld surface studies have also been performed for complex 2.
European Journal of Chemistry, Volume 11, pp 342-350; doi:10.5155/eurjchem.11.4.342-350.2045

Abstract:
A preliminary study to provides insight into the kinetic and thermodynamic assessment of the reaction mechanism involved in the non-oxidative dehydrogenation (NOD) of propane to propylene over Cr2O3, using a density functional theory (DFT) approach, has been undertaken. The result obtained from the study presents the number of steps involved in the reaction and their thermodynamic conditions across different routes. The rate-determining step (RDS) and a feasible reaction pathway to promote propylene production were also identified. The results obtained from the study of the 6-steps reaction mechanism for dehydrogenation of propane into propylene identified the first hydrogen abstraction and hydrogen desorption to be endothermic. In contrast, other steps that include propane’s adsorption, hydrogen diffusion, and the second stage of hydrogen abstraction were identified as exothermic. The study of different reaction routes presented in the energy profiles confirms the Cr-O (S1, that is, the reaction pathway that activates the propane across the Cr-O site at the alpha or the terminal carbon of the propane) pathway to be the thermodynamically feasible pathway for the production of propylene. The first hydrogen abstraction step was identified as the potential rate-determining step for defining the rate of the propane dehydrogenation process. This study also unveils that the significant participation of Cr sites in the propane dehydrogenation process and how the Cr high surface concentration would hinder the desorption of propylene and thereby promote the production of undesired products due to the stronger affinity that exists between the propylene and Cr-Cr site, which makes it more stable on the surface. These findings thereby result in Cr-site substitution suggestion to prevent deep dehydrogenation in propane conversion to propylene. This insight would aid in improving the catalyst performance.
, , Awa Boubou Sall, , Bara Ndiaye,
European Journal of Chemistry, Volume 11, pp 364-369; doi:10.5155/eurjchem.11.4.364-369.2046

Abstract:
Cucurbits are largely grown in tropical and subtropical areas for nutritional and medicinal purposes. In Senegal, two species, watermelon (Citrullus lanatus) and pumpkin (Cucurbita pepo), are cultivated and their use include consumption of flesh or the whole fruit. In general, people don’t give importance to seeds which can have nutritional properties of great interest. Hence, the relevance of this study whose objective is to assess the nutritional and therapeutic properties of seeds. For that purpose, the seeds of watermelon and pumpkin were air-dried, manually shelled, ground, and subjected to assays including physicochemical determination, characterization of oils, phytochemical screening and antioxidant analysis. Proteins (28.46 - 32.85 %), fat (36.3 - 39.7 %) and carbohydrates (23.6 - 13.9 %) were the main chemical components found in watermelon and pumpkin seeds. Micro-elements such as potassium, magnesium, phosphorous, calcium, and iron were also found with potassium showing the highest levels as 1026.07 and 635.00 mg/100 g for watermelon and pumpkin, respectively. Magnesium and phosphorous were the following minerals in terms of level content. The unsaturated fatty acids (UFAs) were predominant in seed oils with the linoleic acid most representative as 73.01 and 35.90% for watermelon and pumpkin, respectively. From the saturated fatty acids (SFAs), the palmitic acid was the most important. Phytochemical components in seeds include the presence of alkaloids, cardiac glycosides, flavonoids, and tannins in the ethanolic extracts of pumpkin and watermelon seeds. Regarding to the radical scavenging activity, relatively close values have been obtained for fractions from the ethanolic watermelon extract, the aqueous fraction showing the highest antioxidant activity (26.82%). For pumpkin, the highest values were registered for ethyl acetate and aqueous fractions as 36.17 and 35.36%, respectively. Therefore, seeds from watermelons and pumpkin cultivated in Senegal exhibited interesting nutritional and antioxidant properties which argue in favor of their use to overcome malnutrition issues.
European Journal of Chemistry, Volume 11, pp 370-376; doi:10.5155/eurjchem.11.4.370-376.2048

Abstract:
This study reports on the chemical compositions of the essential oil of Rosmarinus officinalis L. (Rosemary) grown in Mersin, Turkey. The essential oil of rosemary was obtained by hydrodistillation method, and the yield of rosemary oil was found to be about 1.2 % (v:w). The hydrodistilled volatile oil was analyzed by gas chromatography and mass spectrometry techniques. Forty-five components were identified in the essential oil of R. officinalis, which represented 100% of the total essential oils. The oxygenated monoterpenes content possessed the highest value, 64.78% of the oil, among which eucalyptol (33.15%) and camphor (10.31%) were the most abundant components. In addition, the oil contained mainly monoterpene hydrocarbons, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, and diterpenes. The least amount of diterpenes were found in the content of the oil. Isopimara-9 (11),15-diene (0.14%) and α-springene (0.06%) were two compounds determined as diterpene compounds.
European Journal of Chemistry, Volume 11; doi:10.5155/eurjchem.11.4.i-ii.2052

European Journal of Chemistry, Volume 11, pp 280-284; doi:10.5155/eurjchem.11.4.280-284.2010

Abstract:
Ziprasidone (ZPR) is an antipsychotic agent having less solubility. It is used for the treatment of schizophrenia. Complexation of hydrophobic drugs with cyclodextrins leads to enhanced solubility and dissolution. In this study, inclusion complexes were prepared by different methods, using ZPR, β-cyclodextrin (β-CD), and different auxiliary agents like hydrophilic polymer and hydroxy acid (1:1:0.5) to improve the aqueous solubility. The characterization of the ternary complexes was carried out using solubility study, Differential scanning calorimetry (DSC), Powder X-ray diffraction (PXRD), Fourier transformation infrared spectroscopy (FT-IR) and in vitro dissolution studies. DSC, XRD, and FT-IR studies showed interaction in drug, cyclodextrin, and auxiliary agents which are confirmed by enhancement of solubility and dissolution. Spray-dried dispersion showed less crystallinity and higher solubility as compared to the kneading method for both citric acid and Lutrol® F-68. Thus, the investigation concludes that the presence of the auxiliary agent has a synergistic action on complexation with cyclodextrin, which helps to modify the physicochemical properties of the drug.
European Journal of Chemistry, Volume 11, pp 285-290; doi:10.5155/eurjchem.11.4.285-290.2023

Abstract:
Carbonohydrazide was used for synthetizing a new dissymmetrical bis-substituted Schiff base 1-(2'-hydroxybenzylidene)-5-(1'-pyridylethylidene)carbonohydrazone (2). A mono substituted compound (1-(pyridin-2-yl)ethylidene)carbonohydrazide (1) was firstly prepared by condensation reaction of carbonohydrazide and 2-acetylpyridine in 1:1 ratio. Secondly, compound 2 was obtained by condensation reaction of compound 1 and salicylaldehyde in 1:1 ratio. The prepared compounds were characterized by elemental analysis, infrared and 1H and 13C NMR spectroscopy techniques, and the structure of compound 2 was determined by single-crystal X-ray diffraction study. The compound 2 (C15H15N5O2) crystallises in the monoclinic space group P21/c with the following unit cell parameters: a = 8.3683(3) Å, b = 13.9986(4) Å, c = 12.1610(4) Å, β = 97.512(3)°, V = 1412.37(8) Å3, Z = 4, T = 100(2) K, μ(MoKα) = 0.098 mm-1, Dcalc = 1.398 g/cm3, 6057 reflections measured (5.708° ≤ 2Θ ≤ 54.962°), 6057 unique (Rsigma = 0.0395) which were used in all calculations. The final R1 was 0.0474 (I > 2σ(I)) and wR2 was 0.1971 (all data). The oxygen atom O1 and the azomethine nitrogen atom N5 adopt cis-configuration relative to the C8-N4 bond, while O1 adopts trans-configuration with the azomethine nitrogen atom N2 relative to C8-N3 bond. The crystal packing of compound 2 is stabilized by intramolecular O(phenol)–H···N(carbohydrazide) and intermolecular N (carbohydrazide)–H···O (carbo-hydrazide) hydrogen bonds which form layers parallel to [010] axis. Additional C–H···O hydrogen bond consolidate the structure. The carbonohydrazide moiety C=N–N–C(O)–N–N=C fragment and the phenyl ring are almost coplanar; with an angle of 1.73(1)° between their means plans. The dihedral angle between the mean planes of the phenyl and the pyridine rings is 22.267(2)°.
European Journal of Chemistry, Volume 11, pp 261-275; doi:10.5155/eurjchem.11.4.261-275.2020

Abstract:
2-Chloro-3-tosyl-5,5-dimethyl-2-cyclohexenone was subjected to a series of regiospecific Suzuki-Miyaura cross-coupling reactions in suspensions of nine different substituted boronic acids, Pd(OAc)2, P(Ph3)3, K3PO4 and 1,4-dioxane solvent, under sealed tube conditions. The regiospecific substitution of the tosyl-group by the aryl group in preference over the chloride- group was observed. A comparison between the bromo- and tosylate group’s reactivities is highlighted. Using the methodology, the products: 2-chloro-3-aryl-5,5-dimethyl-2-cyclohexenones were isolated in greater than 85% yields. Good quality crystals of three representative compounds were obtained by slow evaporation technique and subjected to single crystal XRD studies, Hirshfeld surface analysis, 3-D energy framework, and molecular docking studies. Crystal data for compound 3; C15H17ClO4S: monoclinic, space group P21/c (no. 14), a = 8.8687(3) Å, b = 10.5537(4) Å, c = 16.6862(7) Å, β = 89.807(3)°, V = 1561.78(10) Å3, Z = 4, T = 290 K, μ(MoKα) = 0.390 mm-1, Dcalc = 1.398 g/cm3, 13623 reflections measured (6.716° ≤ 2Θ ≤ 54.962°), 3570 unique (Rint = 0.0467, Rsigma = 0.0512) which were used in all calculations. The final R1 was 0.0452 (I > 2σ(I)) and wR2 was 0.1019 (all data). Crystal data for compound 5e; C20H18O2FCl: monoclinic, space group P21/c (no. 14), a = 6.4900(5) Å, b = 18.6070(13) Å, c = 14.2146(11) Å, β = 102.324(2)°, V = 1677.0(2) Å3, Z = 4, T = 296(2) K, μ(MoKα) = 0.239 mm-1, Dcalc = 1.309 g/cm3, 25575 reflections measured (6.262° ≤ 2Θ ≤ 52.224°), 3283 unique (Rint = 0.0494, Rsigma = 0.0307) which were used in all calculations. The final R1 was 0.0875 (I > 2σ(I)) and wR2 was 0.2056 (all data). Crystal data for compound 5h; C12H13OSCl: triclinic, space group P-1 (no. 2), a = 6.7517(6) Å, b = 8.8376(9) Å, c = 12.6049(12) Å, α = 109.538(3)°, β = 98.597(3)°, γ = 90.417(3)°, V = 699.52(12) Å3, Z = 2, T = 290 K, μ(MoKα) = 0.410 mm-1, Dcalc = 1.376 g/cm3, 28754 reflections measured (6.114° ≤ 2Θ ≤ 59.288°), 3898 unique (Rint = 0.0544, Rsigma = 0.0349) which were used in all calculations. The final R1 was 0.1101 (I > 2σ(I)) and wR2 was 0.2481 (all data).
European Journal of Chemistry, Volume 11, pp 351-363; doi:10.5155/eurjchem.11.4.351-363.2043

Abstract:
The novel corona virus 2019 (COVID 19) is growing at an increasing rate with high mortality. Meanwhile, the cytokine storm is the most dangerous and potentially life-threatening event related to COVID 19. Phyto-compounds found in existing Ayurveda drugs have the ability to inhibit the Interleukin 6 (IL-6R) and Interleukin 1 (IL-1R) receptors. IL-6R and IL-1R receptors involve in cytokine storm and recognition of phytochemicals with proven safety profiles could open a pathway to the development of the most effective drugs against cytokine storm. In this study, we intend to perform an in silico investigation of effective phyto compounds, which can be isolated from selected medicinal herbs to avoid cytokine storm, inhibiting the IL-6 and IL-1 receptor binding process. An extensive literature survey followed by virtual screening was carried out to identify phytochemicals with potential anti-hyper-inflammatory action. Flexible docking was conducted for validated models of IL-1R and IL-6R-α with the most promising phytochemicals at possible allosteric sites using AutoDock Vina. Molecular dynamics (MD) studies were conducted for selected protein-ligand complexes using LARMD server and conformational changes were evaluated. According to the results, taepeenin J had Gibbs energy (ΔG) of -10.85 kcal/mol towards IL-1R but had limited oral bioavailability. MD analysis revealed that taepeenin J can cause significant conformational movements in IL-1R. Nortaepeenin B showed a ΔG of -8.5 kcal/mol towards IL-6R-α with an excellent oral bioavailability. MD analysis predicted that it can cause significant conformational movements in IL-6R-α. Hence, the evaluated phytochemicals are potential candidates for further in vitro studies for the development of medicine against cytokine storm on behalf of SARS-COV-2 infected patients.
Mina Mikhael, Mary Hanna, Evana Halaka, ,
European Journal of Chemistry, Volume 11, pp 314-318; doi:10.5155/eurjchem.11.4.314-318.2022

Abstract:
We are evaluating the proposition that compounds with pronounced tendencies to crystallize as kryptoracemates contain molecular fragments responsible for such a property. Why Sohncke space groups display such a tendency is not currently known, but one such fragment is the [tris(2-aminoethyl)amine-N,N',N'',N'''] ligand when attached to cobalt(III). Therefore, proceeding to test the concept further, we examined the title compound and found a previously unknown kryptoracemic species, described in what follows. It seems then that the prescription has some merit and should be examined further inasmuch as guidelines for the occurrence of kryptoracemic crystallization are scant, if any exist. Crystal data for C6H20Cl3CoN4O: monoclinic, space group P21 (no. 4), a = 7.6672(3) Å, b = 15.7153(5) Å, c = 10.7170(4) Å, β = 92.964(2)°, V = 1289.59(8) Å3, Z = 4, T = 100(2) K, μ(CuKα) = 16.026 mm-1, Dcalc = 1.697 g/cm3, 13406 reflections measured (8.26° ≤ 2Θ ≤ 133.402°), 3976 unique (Rint = 0.0300, Rsigma = 0.0519) which were used in all calculations. The final R1 was 0.0220 (I > 2σ(I)) and wR2 was 0.0459 (all data).
European Journal of Chemistry, Volume 11; doi:10.5155/eurjchem.11.4.iii-vii.2053

European Journal of Chemistry, Volume 11, pp 385-395; doi:10.5155/eurjchem.11.4.385-395.2030

Abstract:
A very simple, non-extractive and new spectrophotometric method for the swift determination of trace amount of vanadium using salicylaldehyde-benzoylhydrazone (Sal-BH) has been developed. Sal-BH undergoes a reaction in a slightly acidic solution (0.0016-0.0032 M H2S04) with vanadium to give a light greenish-yellow chelate, which has an absorption maximum at 392 nm. The reaction is instantaneous and absorbance remains stable for over 24 hrs. The average molar absorption co-efficient and Sandell’s sensitivity were found to be 2.5039×105 L/mol.cm and 1.0 ng/cm2 V, respectively. Beer’s law was obeyed for 0.001-30 mg/L of V, providing a detection limit of 0.1 µg/L of V and RSD 0-2 %. The stoichiometric composition of the chelate is 1:1 (V:Sal-BH). Interference study shows that a large excess of over 60 cations, anions, and some common complexing agents (such as chloride, azide, tartrate, EDTA and SCN‑, etc.) satisfy the tolerance limit. The developed method was successfully used in the determination of vanadium in several standard reference materials as well as in some environmental waters, biological fluids, soil, food and pharmaceutical samples and solutions containing both vanadium (IV) and vanadium (V). The results of the proposed method for assessing biological, food and vegetable samples were comparable with ICP-OES and AAS were found to be in excellent agreement. The method has high precision and accuracy (s = ±0.01 for 0.5 mg/L).
European Journal of Chemistry, Volume 11; doi:10.5155/eurjchem.11.3.i-ii.2041

European Journal of Chemistry, Volume 11, pp 179-186; doi:10.5155/eurjchem.11.3.179-186.1977

Abstract:
A simple and efficient synthesis of substituted pyrazolo[1,5-a]pyrimidine derivatives has been developed by the use of ultrasound. 5-Methyl-4-phenyl-1H-pyrazol-3-amine required for the synthesis of pyrazolo[1,5-a]pyrimidine derivatives has been easily obtained by the reaction of 3-(dimethylamino)-2-phenylacrylonitrile (formed from readily available 2-phenylacetonitrile) with hydrazine hydrate in refluxing ethanol. The 5-aminopyrazole was then reacted with various formylated active proton compounds in presence of KHSO4 in aqueous medium under ultrasound irradiation to give the desired products. The chemical structures of the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and Mass spectral data. X-ray crystallographic study of a selected compound 6-(4-chlorophenyl)-2-methyl-3-phenylpyrazolo[1,5-a]pyrimidin-7-amine (7c) was performed to ascertain the regioselectivity of the reaction. Crystal data for compound 7c: Triclinic, space group P-1 (no. 2), a = 8.0198(3) Å, b = 14.0341(6) Å, c = 14.2099(6) Å, α = 87.672(2)°, β = 83.902(2)°, γ = 89.120(2)°, V = 1588.87(11) Å3, Z = 4, T = 293(2) K, μ(MoKα) = 0.248 mm-1, Dcalc = 1.400 g/cm3, 12918 reflections measured (4.012° ≤ 2Θ ≤ 49°), 5152 unique (Rint = 0.0411, Rsigma = 0.0429) which were used in all calculations. The final R1 was 0.0486 (I > 2σ(I)) and wR2 was 0.1320 (all data).
European Journal of Chemistry, Volume 11, pp 255-260; doi:10.5155/eurjchem.11.3.255-260.2019

Abstract:
The structure of the title compound, 4-(dimethylamino)pyridin-1-ium-2,5-dichloro-3,6-dioxocyclohexa-1,4-diene-1,4-bis(olate) 4-dimethylaminopyridine water undeca-solvate, C57H87Cl5N12O21, obtained from interaction between chloranilic acid (caH2), and dimethyl aminopyridine (DMAP) has been determined by single crystal X-ray diffraction. The title compound, (DMAPH)5(ca)2.5·(DMAP)·11H2O, crystallized in the triclinic crystal system with space group, P (no. 2), a = 13.3824(15) Å, b = 13.4515(17) Å, c = 19.048(2) Å, α = 86.014(4)°, β = 88.821(4)°, γ = 86.367(4)°, V = 3413.3(7) Å3, Z = 2, T = 100(2) K, μ(MoKα) = 0.294 mm-1, Dcalc = 1.414 g/cm3, 59413 reflections measured (3.76° ≤ 2Θ ≤ 56°), 16405 unique (Rint = 0.0517, Rsigma = 0.0589) which were used in all calculations. The final R1 was 0.0460 (I ≥ 2σ(I)) and wR2 was 0.1271 (all data). Using supramolecular chemistry principles, proton donors (chloranilic acid) and acceptor (DMAP) were combined to generate a multicomponent hydrogen-bonded system. Due to the presence of protonated bases (DMAPH+), the dominant interactions are the N+-H···O hydrogen bonds, whereas the negative charges of an acceptor from the chloranilate dianion (ca2-) are delocalized. Additionally, three sets of water clusters in the title compound were identified, namely a cyclic pentamer, a linear, and an acute-shaped trimer water cluster. It was further observed that strong hydrogen bond interactions occurred between the solvated aqua molecule(s) acting as a proton donor and the neutral DMAP acting as a proton acceptor. The crystal packing is further stabilized by O-H···Cl and C-H···Cl weak halogen interactions. The lattice metric strength is further held by observed π-π stacking interactions (centroid-centroid) with inter centroid distances between sets of the DMAPH rings of 3.624(3), 3.642(4), 3.739(3), 3.863(3) and 3.898(3) Å, respectively.
European Journal of Chemistry, Volume 11, pp 250-254; doi:10.5155/eurjchem.11.3.250-254.2014

Abstract:
The title compound, tetra(µ-2-3-(2-oxybenzylideneamino)-1-hydroxypropan-2-olato)-4-nitrophenolatedi-cobalt(III)-di-iron(III) dimethylsulfoxidehexasolvate, crystallizes in the monoclinic space group P21/c and represent the first example of heterometallic CoIII-FeIII complex with 3-((5-nitro-2-hydroxybenzylidene)amino)propane-1,2-diol/2-(((2,3-dihydroxy propyl)iminio)methyl)-4-nitrophenolate) - a hydroxyl rich Schiff base ligand which was obtained in situ. Crystal data for C52H74Cl2Co2Fe2N8O26S6 (M = 1720.01 g/mol): monoclinic, space group P21/c (no. 14), a = 16.353(3) Å, b = 15.234(2) Å, c = 15.201(3) Å, β = 113.99(2)°, V = 3460.0(12) Å3, Z = 2, T = 173(2) K, μ(MoKα) = 1.225 mm-1, Dcalc = 1.651 g/cm3, 14130 reflections measured (5.7° ≤ 2Θ ≤ 57.266°), 7748 unique (Rint = 0.1051, Rsigma = 0.2148) which were used in all calculations. The final R1 was 0.0914 (I > 2σ(I)) and wR2 was 0.2279 (all data). The metal ions have distorted octahedral coordination geometry and are joined in a tetranuclear {Co2Fe2(µ-O)6} core by O-bridging atoms from the ligand. There are numerous intermolecular interactions occurring between the components of the crystal: π-hole interaction between NO2···NO2 groups of the ligands, short S···S, O···O and C··· C interactions and weak and strong hydrogen bonds.
European Journal of Chemistry, Volume 11, pp 198-205; doi:10.5155/eurjchem.11.3.198-205.1988

Abstract:
New fluorine-substituted polyfunctional pyrimido-[1,2-b]-[1,2,4]triazines and [1,3,5]-triazino[1,2-b]-[1,2,4]triazines were synthesized via the reaction between 3-amino-6-(2-aminophenyl)-1,2,4-triazin-5(2H)-one with polyfunctional oxygen/sulfur/nitrogen reagents under different conditions. Structures of the target compounds were deduced by elemental analysis and spectral measurements (IR, 1H/13C NMR, and mass spectra). According to the obtained inhibitor assay results, the inhibition activity of the new fluorine-substituted 1,2,4-triazines toward CDK2 decreased in the order of compounds 3 > 8 > 9 > 6 > 13 > 15.
European Journal of Chemistry, Volume 11, pp 194-197; doi:10.5155/eurjchem.11.3.194-197.1980

Abstract:
This is a quality control study and analysis of Portland cement taken from four Pakistani cement plants (Deewan, Kohat, Lucky and Maple Leaf). These four samples were analysed and the determination of major oxides present was carried out. Loss on ignition and the percentage of insoluble residue was also determined. Our research shows percentage of major oxides present in these four samples i.e. calcium oxide, silicon dioxide, aluminium oxide, iron oxide, sulphur trioxide and magnesium oxide. According to the American Society for Testing and Materials Cement (ASTM C150), the percentage of these oxides, loss on ignition and insoluble residue of these four plants are within the specified quality control range. The present study compared the quality of different oxides at the Portland cement brands in Pakistan. The percentages of SiO2,SO3, CaO, Al2O3,MgO and Fe2O3 were calculated according to American Society for Testing and Materials (ASTM C150) uniform standards. The percentages of all of the brands were within the limits specified by the standard (ASTM C150).
European Journal of Chemistry, Volume 11, pp 217-222; doi:10.5155/eurjchem.11.3.217-222.2008

Abstract:
Metal-organic frameworks (MOFs) are a new class of nanoporous materials that have attracted much attention for the adsorption of small molecules, due to the large size of the cavities. In this study, we investigate the adsorption and diffusion of hydrogen (H2) and carbon monoxide (CO) guest molecules to the UiO-66 framework, as one of the most widely used MOFs, by using Monte Carlo simulation method. The results prove that an increment in the temperature decreases the amount of the adsorbed H2 and CO on the UiO-66 framework. While an enhancement of the pressure increases the amount of the adsorbed H2 and CO on the UiO-66 framework. Besides, the adsorption of H2 and CO on UiO-66 is the type I isotherm. The calculated isosteric heat for CO/UiO-66 is slightly higher than that of H2/UiO-66. The means of square displacement (MSD) value is less for CO molecule; hence, the movement of the guest molecule within the host cavity slows down and the guest molecule travels a shorter distance over a period of time. The guest molecule with higher molecular mass possesses less mobility, and therefore, it will have less permeability.
Zineb Hacini, , Ibtisam Bourghra, , , Zineb Debba
European Journal of Chemistry, Volume 11, pp 213-216; doi:10.5155/eurjchem.11.3.213-216.1993

Abstract:
The experiment was conducted on alfalfa seeds that were brought from Marjajah in the city of Touggourt. After the traditional extraction process, some of its physical properties were measured, including, refractive index, pH, with a yellowish green color, odor, prick, and transport value of 363 cm/S and on blood clotting. The results showed that the seed extract of alfalfa has an effect on blood clotting on the internal and external pathway by the prothrombin rate (TP) obtained that sample 1 has the largest clotting time of 22 seconds and by the time of cefalin kaolin (TCK), the highest coagulation time for sample 2 by 46 seconds. The prothrombin rate and the time of cefalin kaolin chronometer tests also show that alfalfa seed extract exercises an important anticoagulant activity compared to the two coagulation methods, because this activity is more pronounced towards the internal pathway that the external pathway passes, that is, the alfalfa seed extract is better than the normal witness and less than the positive witness heparin.
Brock Anton Stenfors,
European Journal of Chemistry, Volume 11, pp 245-249; doi:10.5155/eurjchem.11.3.245-249.2017

Abstract:
N-Benzyl-4-methylbenzenesulfonamides were prepared via a two-step synthetic process involving the treatment of 4-methylbenzenesulfonyl chloride with a primary amine to give the corresponding 4-methylbenzenesulfonamide. Benzylation of the sulfonamide affords the substituted N-benzyl-4-methylbenzenesulfonamides. The similarities between the two steps of synthesis lend credence to the development of a one-pot synthesis of substituted N-benzyl-4-methylbenzenesulfonamides from 4-methylbenzenesulfonyl chloride. This method was applied to the synthesis of N-allyl-N-benzyl-4-methylbenzenesulfonamide and characterized through spectroscopic and crystallographic means. The crystal structure of N-allyl-N-benzyl-4-methylbenzenesulfonamide was obtained by single-crystal X-ray diffraction. The crystal structure reveals an orthorhombic Pna21 space group with cell parameters a = 18.6919 (18) Å, b = 10.5612 (10) Å, c = 8.1065 (8) Å, V = 1600.3 (3) Å3 and Z = 4, T = 173.15 K, μ(MoKα) = 0.206 mm-1, Dcalc = 1.251 g/cm3, 14455 reflections measured (4.36° ≤ 2Θ ≤ 54.96°), 3619 unique (Rint = 0.0439, Rsigma = 0.0429) which were used in all calculations. The final R1 was 0.0428 (I > 2σ(I)) and wR2 was 0.1079 (all data). Molecules are linked through C-H···N hydrogen bonds and C-H···π interactions.
, Eppakayala Laxminarayana,
European Journal of Chemistry, Volume 11, pp 206-212; doi:10.5155/eurjchem.11.3.206-212.1992

Abstract:
A facile and highly efficient FeF3-catalyzed method has been developed for the direct synthesis of functionalized dihydropyrimidines from readily available starting materials via Biginelli reaction. These reactions proceed at low-catalyst loadings with high functional group tolerance under mild conditions. This method provides efficient reusability of the catalyst and good to excellent yields of the products, making the protocol more attractive, economical, and environmentally benign. FeF3 is an attractive catalyst for the Biginelli reaction because of its high acidity, thermal stability and water tolerance.
, Amna Bint Wahab Elrashid Mohammed Hussien,
European Journal of Chemistry, Volume 11, pp 187-193; doi:10.5155/eurjchem.11.3.187-193.1976

Abstract:
A quantitative structure activity relationship (QSAR) model for a series of N-(1-benzyl-3,5-dimethyl-1H-pyrazole-4-yl) benzamide derivatives having autophagy inhibitory activities as potent anticancer agents was developed by the multiple linear regressions (MLR) method. In this study, previous compounds were used in the model development were divided into a set of fifteen compounds as training set and set of four compounds as test set. A model with high prediction ability and high correlation coefficients was obtained. This model showed r = 0.968, r2 = 0.937 and Q2 = 0.880, the QSAR model was also employed to predict the experimental compounds in an external test set, and to predict the activity of a new designed set of 3,5-dimethyl-4-substituted-pyrazole derivatives (1-15), result showed that compound 3 has the most promising inhibition activity (EC50 = 0.869 μM) against human pancreatic ductal adenocarcinoma cell MIA PaCa-2 compared to the reference chloroquine with (EC50 = 14 μM). Thus, the model showed good correlative and predictive ability. Docking studies was performed for designed compounds, docking analysis showed the best compound 1 with high docking affinity of -24.8616 kcal/mol.
European Journal of Chemistry, Volume 11; doi:10.5155/eurjchem.11.3.iii-vi.2042

European Journal of Chemistry, Volume 11, pp 223-234; doi:10.5155/eurjchem.11.3.223-234.2004

Abstract:
Quinoline and benzofuran moieties are commonly used for the synthesis of therapeutically beneficial molecules and drugs since they possess a wide range of pharmacological activities including potent anticancer activity as compared to other heterocyclic compounds. Many of well-known antimalarial, antimicrobial, anti-helminthic, analgesic, anti-inflammatory, antiprotozoal, and antitumor compounds contain quinoline/benzofuran skeleton. The aim of this study was to analyze ten new quinoline and eighteen benzofuran derivatives for carcinoma cell line growth inhibition and to predict possible interactions with the target. The anticancer activity of these compounds against colon cancer (HCT-116) and triple-negative breast cancer (MDA-MB-468) cell lines was determined and performed molecular docking to predict the possible interactions. Among ten quinoline derivatives, Q1, Q4, Q6, Q9, and Q10 were found to be the most potent against HCT-116 and MDA-MB-468 with IC50 values ranging from 6.2-99.6 and 2.7-23.6 μM, respectively. Using the IC50 values, a model equation with quantitative structure activity relationship (QSAR) was generated with their descriptors such as HBA1, HBA2, kappa (1, 2 and 3), Balaban index, Wiener index, number of rotatable bonds, log S, log P and total polar surface area (TPSA). The effect of benzofuran derivatives was moderate in cytotoxicity tests and hence only quinolines were considered for further analysis. The molecular docking indicated the mammalian / mechanistic target of rapamycin (mTOR), Topoisomerase I and II as possible targets for these molecules. The predicted results obtained from QSAR and molecular docking analysis of quinoline derivatives showed high correlation in comparison to the results of the cytotoxic assay. Overall, this study indicated that quinolines are more potent as anticancer agents compared to benzofurans. Further, compound Q9 has emerged as a lead molecule which could be the base for further development of more potent anticancer agents.
European Journal of Chemistry, Volume 11, pp 235-244; doi:10.5155/eurjchem.11.3.235-244.2011

Abstract:
The use of computational chemistry as an effective means of designing eco-friendly organic corrosion inhibitors has been greatly enhanced by the development of Density Functional Theory (DFT). In this study, the inhibitory activity of four antiretroviral drugs, namely, lamivudine, emtricitabine, didanosine and stavudine, was analyzed by this theory. The quantum chemical parameters/descriptors calculated using DFT at B3LYP/6-31G(d) level were used to explain the mechanism of electron transfer between the inhibitors and the copper surface. The results showed that these compounds adsorb on copper surface. It is important to consider the effect of films formed by the adsorption products. In addition, the Fukui functions and the dual descriptor were used as indicators to locate the electrophilic and nucleophilic attack sites within each compound. Finally, the DFT has enabled to accurately predict the adsorption properties and the good inhibition performance of the molecules in the solution studied.
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