Potassium (3-Methyl-2-oxido-1,2,5-oxadiazol-4-yl)dinitromethanide

Furoxan derivatives enriched with explosophoric functionalities are promising compounds in the preparation of novel energetic materials. Herein, a previously unknown potassium (3-methyl-2-oxido-1,2,5-oxadiazol-4-yl)dinitromethanide (also referred to as potassium 4-dinitromethyl-3-methylfuroxanate) was synthesized via tandem nitration-reduction reactions of an available (furoxanyl)chloroxime. The structure of the synthesized compound was established by elemental analysis, IR, 1H, 13C and 14N NMR spectroscopy. Thermal stability and mechanical sensitivity of the prepared compound toward impact and friction were experimentally determined.

Synthesis and Characterisation of Structural and Electrical Properties of CuMn2O4 Spinel Compound

CuMn2O4 was synthesized by the solid-state method. MnO2 and CuO were used as precursors. The optimum temperature of synthesis was 850°C. XRD results showed that the prepared compound had a cubic structure with Fd3 ̅m space group. The lattice constant and unit cell volume were a=8.359Å and V=584.14A°3 respectively. The grain size was calculated by the Debye-Scherrer method and was 33.49 nm for CuMn2O4 annealed at 850°C. The experimental density was calculated and compared to the theoretical density. The results were ρt= 5.399 gr/cm3 and ρE = 5.24 gr/cm3. The electrical properties of the compound showed that it behaves like a semiconductor, and the activation energy of the compound was 0.1535 eV. KEYWORDS Activation energy, copper manganite (CuMO), mixed oxide, solid-state reaction, spinel

Synthesis and spectral characterization of selective pyridine compounds as bioactive agents

Starting from 3-cyano-4,6-distyrylpyridin-2(1H)-thione (1), the compound N-(4-chlorophenyl)-2-((3-cyano-4,6-distyrylpyridin-2-yl)thio)acetamide (2) was prepared. Compound (2) underwent cyclization upon heating in ethanolic sodium ethoxide solution to give the corresponding cyclized form 3-amino-N-(4-chlorophenyl)-4,6-distyrylthieno[2,3-b]pyridine-2-carboxamide (3). The elemental analyses and spectroscopic data of compounds (2) and (3) are in agreement with their proposed structures. Their insecticidal activity against cowpea aphid, Aphis craccivora Koch, was studied. The results of insecticidal activity for compounds (2) and (3) against the nymphs and the adults of the tested insects exhibited that compounds (2) and (3) have a higher insecticidal activity than that of acetamiprid, a reference insecticide, after 24 h of treatment.

Synthesis of Fe3O4 and Fe2O3 nanoparticles using hybrid electrochemical-thermal method

Nanocrystalline Fe3O4 and Fe2O3 particles were successfully synthesized by an innovative hybrid electrochemical-thermal method. The as-prepared compound was calcined for an hour from 100 to 600oC temperatures. The crystallinity, morphology and chemical state of the synthesized powders were characterized by XRD, TG-DTA, SEM/EDS, FT-IR, and UV–Vis spectral techniques after calcinations. The Brunauer–Emmett–Teller (BET) plots confirmed that iron oxide nanoparticles (NPs) calcined at 400oC has a surface area of 18.28 m2 g-1 with a total pore volume of 0.2064 cc g-1. From XRD pattern it is revealed that the precursor calcined at lower temperature (100-400oC) correspond to Fe3O4,while the ones calcined at higher temperature follow Fe2O3 pattern. The morphology of iron oxide NPs calcined at different temperatures were studied with scanning electron microscope (SEM) and exhibits spherical shaped geometries with average diameters of 80-150nm. Bangladesh J. Sci. Ind. Res.55(3), 221-228, 2020

Synthesis of Silica-Salen Derivative from Rice Husk Ash and its Use for Extraction of Divalent Metal Ions Co(II), Ni(II) and Cu(II)

Rice husk ash (RHA) was used to prepare sodium silicate, which in turn was functionalized with 3-(chloropropyl)triethoxysilane employing the sol-gel technique to form RHACCl. Chloro group in RHACCl was replaced with iodo group forming RHACI. Ethylenediamine was immobilized on RHACI in order to prepare it for the reaction with salicylaldehyde to form a silica derivative-salen. FT-IR analysis indicated the presence of secondary amine and –NH and C=N absorption bands. XRD analysis revealed the occurrence of the broad diffused peak with maximum intensity at 22–23° (2θ). BET measurements showed also that the surface area of the prepared compound is 274.55 m2/g. Elemental analysis proved the existence of nitrogen in the structure of the prepared compound. The silica derivative-salen showed high potential for extraction and removal of heavy contaminating metal ions Ni(II), Cu(II), and Co(II) from aqueous solutions. The kinetic study demonstrates that the adsorption of the metal ions follows the pseudo-second order.

Synthesis, characterization and antibacterial activity of Methyl (2R)-2-benzamido-2-{[(1R)-2-methoxy-2-oxo- 1-phenylethyl]amino}acetate

The present work covers the recent synthetic of methyl (2R)-2-benzamido-2-{[(1R)-2-methoxy-2-oxo-1-phenylethyl]amino}acetate, via N-alkylation of methyl a-azido glycinate N-benzoylated with methyl 2-amino-2-phenylacetate in methylene chloride and in presence of triethylamine as basic catalyst. The structure of the prepared compound was determined by spectroscopic methods: 1H-NMR, 13C-NMR, MS data, elemental analysis and confirmed by X-Ray diffraction. This compound was screened in vitro for its antibacterial activity against Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Salmonella enteric). The MIC values confirmed that the title compound had a bactericidal effect against the strains tested.

5-[3-(4-Bromophenyl)-1-(2,5-dimethoxyphenyl)-3-oxopropyl]-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-tri-one

The title compound was prepared by a two-step reaction. The first step was the formation of a chalcone derivative using Claisen–Schmidt condensation, which was followed by the Michael addition of the formed chalcone with 1,3-dimethylbarbituric acid. The structure of the prepared compound was established by spectral data: FTIR, HRESIMS, 1H- and 13C-NMR.

Effect of Polymer Blends on Hydroxyapatite Using Sol–Gel Method

Hydroxyapatite (HA) was synthesized using polyethylene glycol with polyvinyl alcohol as blends which gave changes in stability to the synthesized HA. The addition of Polymer blends altered the morphology and particle size which carries more advantages. The single phase formation and lattice parameters of the prepared compound were analyzed by powder XRD technique. Phase transition and various functional groups were confirmed by FTIR analysis. The morphology of the synthesized material was determined by SEM images and composition of the materials was analyzed through EDAX.

ABOUT THERMAL STABILITY OF BISMUTH(III) IODINE ETIOPORPHYRIN II COMPLEX

For the first time, a complex of bismuth(III) with iodine and etioporphyrin II is reported. It was prepared by reacting etioporphyrin II and bismuth(III) iodide in pyridine in Ar atmosphere. The prepared compound was characterized by FT-IR, 1H-NMR, UV-VIS spectroscopy and mass spectrometry. One intense line at m/z 684.990 attributed to the complex without the iodine atom is observed in the mass spectrum. This is in agreement with the data indicating that bismuthporphyrin complexes generally have low stability. Analysis of FT-IR spectra obtained at room temperature and at 145°С is reported. Priroda15 DFT package was used for optimization of complex geometry and calculation of the IR spectrum. Calculations were done using BPE functional and L1 basis set under relativistic approximation of Dyall Modified Dirac. Assignment of the vibrational frequencies is reported. Collected data indicate that the complex of bismuth(III) with iodine and etioporphyrin II is not stable and easily hydrolyses when exposed to air forming the corresponding hydroxocomplex. This transformation does not change significantly the dynamics of the porphyrin ring.

Synthesis of New Nucleoside Analogues From Benzimidazole and Evaluation of Their Antimicrobial Activity

Our goal in this research, some new nucleoside analogues was synthesized. Starting from ?-D glucose which was converted to per acetylated ?-D gluco pyronoside then converted to active from(1-Bromo Sugar (2) as a sugar moiety.The base moiety 2-substituted benzimidazole was prepared from condensation of phenylene diamine with different aromatic aldehydes, which were subjected to amino alkylation via Mannich reaction forming new nucleobase derivatives. Condensation of nucleobase with bromo sugar through nucleophilic substitution of anomeric carbon with nitrogen forming new protected nucleoside analogues then hydrolyzed with sodium methoxide in methanol to obtain our target, the free nucleoside analogues. All prepared compound were identified by FT-IR Spectroscopy and some of them with H1 –NMR and C13-NMR Spectroscopy. The synthesized nucleoside analogues were screened for their antibacterial activity in vitro against four types of bacteria including, Bacillus Staphylococcus, aureus (Gram Positive), E.Coli and Pseudoman as (Gram Negative).Also were screened against four types of Fungi (Aspergines flurs, Aspergillus fumgntnts, Aspergillus niger and pencillum).