Nanoporous starch materials were successfully prepared by a sustainable synthetic process. In this method, some available economic cationic, anionic and nonionic templates like CTAB, SDS and Tween 80 in the presence of borax, as a green and low-cost cross-linker, were used to synthesize the desired cross-linked nanoporous starch in the aqueous phase at relatively low temperature. The obtained materials were characterized by SEM, FT-IR, TGA, DSC and N2 adsorption/desorption methods. While SEM analysis confirmed the porous nature of the materials, BET measurement showed that the materials can have a specific surface area of 65 m² g-1. Cross-linked nanoporous starch was found to be an efficient, inexpensive, easy to prepare, green adsorbent in the removal of methylene blue and methyl orange from wastewater. The synthesized material was found to be highly efficient in controlled adsorption and desorption of ciprofloxacin, which can be applied in drug delivery.

In the present study, we have designed and synthesized a new magnetically recoverable, nanocatalyst of Ag/Fe3O4@starch. The successful synthesis and the structure of the nanocatalyst were confirmed and evaluated with several analytical techniques including XRD, EDX, VSM, FT-IR, TEM and TGA. The impact and efficiency of Ag/Fe3O4@starch were successfully investigated in the one-pot synthesis of desired 4H-pyrans and tetrahydro-4H-chromenes using three-component condensation of various aldehydes, malononitrile, and 1,3-diketoesters or cyclic 1,3-diketones. The magnetic nanocatalyst was easily recovered and reused with high catalytic activity even after up to five runs.

Abstract. Salicylic acid (mod)-Ag/TiO2NTs/Ti photocatalyst plates were prepared using chemical modification process of TiO2-nanotubes/Ti plates with salicylic acid and silver nanoparticles. Morphology studies exhibit that esterification between salicylic acid and -OH groups on TiO2 surface as well as deposition of Ag has been led to formation of uniform deposits on the walls of TiO2-nanotubes/Ti plates. The photocatalytic activity of the plates was tested on the degradation of Methylene Orange (MO) dye. The activity tests showed that the photodegradation efficiency for salicylic acid(mod)-Ag/TiO2NTs/Ti is higher than for Ag/TiO2NTs/Ti, salicylic acid(mod)/TiO2NTs/Ti and TiO2NTs/Ti plates, showing the integration the photocatalytic advantages of both Ag-TiO2 and salicylic acid-Mod-TiO2 composites. The modified plates can eliminate 96.6% of MO under UV light irradiation after 1 h, while can be recycled 4 times with 72.9% degradation ratio. Improved surface adsorption of MO, fast charge separation and slow electron-hole recombination are the main factors being responsible for the increase the photocatalytic activity of salicylic acid (mod)-Ag/TiO2-nanotubes/Ti plate.

Resumen. Se prepararon placas de fotocatalizador de ácido salicílico (mod)-Ag/TiO2NTs/Ti, utilizando un proceso de modificación química de placas de nanotubos/TiO2-TiO2, con ácido salicílico y nanopartículas de plata. Los estudios morfológicos muestran que la esterificación entre el ácido salicílico y los grupos -OH en la superficie de TiO2, así como la deposición de Ag, ha llevado a la formación de depósitos uniformes en las paredes de las placas de nanotubos de TiO2/ Ti. La actividad fotocatalítica de las placas se probó en la degradación del colorante naranja de metileno (MO). Las pruebas de actividad mostraron que la eficiencia de fotodegradación para el ácido salicílico (mod)-Ag /TiO2NTs/Ti es mayor que para las placas Ag/TiO2NTs/Ti, ácido salicílico (mod)/TiO2NTs/Ti y TiO2NTs/Ti, mostrando la integración de las ventajas fotocatalíticas de los compuestos de Ag-TiO2 y ácido salicílico-Mod-TiO2. Las placas modificadas pueden eliminar el 96.6% del MO bajo la irradiación con luz UV después de 1 h, mientras que pueden reciclarse 4 veces con una relación de degradación del 72.9%. La mejora de la adsorción superficial de MO, la rápida separación de la carga y la lenta recombinación del hueco de electrones son los principales factores responsables del aumento de la actividad fotocatalítica del ácido salicílico (mod)-Ag/TiO2-nanotubos/placa de Ti.

In the present research, 1,2-di[N-2-phenylthio-5-azophenylsalicylidene]ethane (H2L¹, 1,3-di[N-2-phenylthio-5-azophenylsali-cylidene]propane(H2L²) and 1,4-di[N-2-phenylthio-5-azophenylsalicylidene]butane (H2L³) were synthesized. ML¹,ML² and ML³ complexes were prepared through the reaction of H2L¹,H2L² and H2L³ with Ni(II) and Co(II) acetate salts. The prepared ligands and their complexes were characterized with FT-IR, ¹H-NMR, elemental analysis, conductivity and magnetic measurements, ESI-mass, UV-Vis spectroscopy and cyclic voltammetry. The complexes had monomeric structure according to the mass spectral data. All of the complexes had a six-coordinated octahedral geometry. The electrochemical behavior of the ligands, Ni(II) and Co(II) complexes was investigated by CV in DMF under argon atmosphere. The results show that the coordination of Ni(II) causes the ligands to be deactivated. The voltammogram of Co(II) complexes shows that the reduction of CoL¹ is harder than CoL³ and CoL² is inactive. Their antibacterial activity was investigated and the complexes exhibited better antibacterial activity than the free ligands against selective bacteria.

Herein we report the synthesis of some novel indeno[1,2-b]benzofuran derivatives by reaction of ninhydrin with cyclic 1,3-dicarbonyl compounds including cyclopentane-1,3-dione, cyclohexane-1,3-dione, dimedone, 4,4-dimethylcyclohexane-1,3-dione, meldrum's acid, barbituric acid, thiobarbituric acid, 1,3-dimethylbarbituric acid and indane-1,3-dione. We also used tetra-propylammonium bromide (TPAB) as an organocatalyst.

We synthesized a new Schiff base ligand by condensation reaction of 4-dimethylaminobenzaldehyde and 1,3-phenylenediamine. Treatment of this Schiff base ligand with Zinc(II) nitrate and Cadmium(II) nitrate in ethanol medium afforded the corresponding metal complexes. The synthesized ligand and complexes were characterized by their UV-Vis, FT-IR and ¹H-NMR, 13C-NMR spectral data and elemental analysis. The spectral data suggest an octahedral geometry for these complexes. Antibacterial activities of both synthesized free ligand and complexes were investigated against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis bacteria. The complexes showed better antibacterial activity in comparison with that of the free ligand against selective bacteria.

This study reports the reduction of α,β-unsaturated ketones 4a-g, formed by condensation of arylglyoxals 2a-g with 1,3-dimethylbarbituric acid (3) by L-cysteine (5) in the presence of phosphotungstic acid as a catalyst. This reaction leads to the formation of 5-[2-aryl-2-oxoethyl ]-1,3-dimethylpyrimidine-2,4,6-triones 6a-g, with no sign of any heterocyclic product formation. The structure of compound 6f was confirmed by X-ray crystallography.

3-Arilaminoisoxazol-5(2H)-onas, substituídas no nitrogênio com grupos benzoxazol e benzotiazol, reagem com trietilamina em etanol, sob refluxo, fornecendo os correspondentes derivados indol e imidazobenzotiazol, respectivamente.

3-Arylaminoisoxazol-5(2H)-ones, substituted on nitrogen with benzoxazole and benzothiazole groups react with triethylamine in ethanol under reflux to afford the corresponding indole and imidazobenzothiazole derivatives, respectively.