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1.
Artigo em Inglês | MEDLINE | ID: mdl-32646353

RESUMO

Aims & Objective: In this work, the multicomponent reaction of aldehydes, benzoylisothiocyanate and alkyl bromides in the presence of ammonium acetate, sodium cyanide and a catalytic amount of KF/Clinoptilolite nanoparticles (KF/CP NPs) in the water at 100oC was investigated. MATERIALS AND METHODS: In these reactions, thiazole derivatives were produced in good to excellent yields and short time. Also, the antioxidant activity was studied for some newly synthesized compounds using the DPPH radical trapping and reducing of ferric ion experiments and comparing results with the synthetic antioxidants (TBHQ and BHT). RESULTS: As a result, the compounds 4b showed excellent DPPH radical trapping and reducing the strength of ferric ion. These compounds have biological potential because of the thiazole core. For this reason, the antimicrobial activity of some synthesized compounds was studied by employing the disk diffusion test on Gram-positive bacteria and Gram-negative bacteria. CONCLUSION: The results of the disk diffusion test showed that these compounds prevented bacterial growth.


Assuntos
Aldeídos/química , Anti-Infecciosos/síntese química , Antioxidantes/síntese química , Brometos/química , Isotiocianatos/química , Tiazóis/síntese química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Catálise , Descoberta de Drogas , Compostos Férricos/química , Sequestradores de Radicais Livres/química , Química Verde , Humanos , Nanopartículas/química , Oxirredução , Tiazóis/farmacologia , Zeolitas/química
2.
Comb Chem High Throughput Screen ; 24(6): 841-848, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33109056

RESUMO

AIM AND OBJECTIVE: In current research, imidazole derivatives are synthesized via a new process of four component reaction of trichloroacetonitrile, amides, alkyl bromides and amino acids catalyzed by zinc oxide nanoparticles (ZnO-NPs) as a simple and recyclable catalyst in water at room temperature. Among investigated compounds, compounds 5b have good results relative to butylated hydroxytoluene (BHT) and 2-tert-butylhydroquinone (TBHQ) as standard antioxidant. The achieved outcomes of disk diffusion experiment showed that these compounds avoided the growth of bacterial. MATERIALS AND METHODS: In this research, all chemicals are purchased from Fluka (Buchs, Switzerland) and employed with any purification. For measuring infrared spectroscopy and melting point, a Shimadzu IR-460 spectrometer and Electrothermal 9100 apparatus are utilized respectively. BRUKER DRX-400 AVANCE spectrometer is used for giving the 1H, and 13CNMR spectra at 400.1 and 100 MHz respectively. For recording mass spectra, A FINNIGAN-MAT 8430 spectrometer with an ionization potential of 70 eV was utilized. The scanning electron microscopy (SEM) employing a Holland Philips XL30 microscope was used for determination of ZnO nanocomposites morphology. X-ray diffraction (XRD) analysis at room temperature using a Holland Philips Xpert X-ray powder diffractometer, with CuKα radiation (λ=0.15406 nm), with 2θ ranging from 20 to 80° was employed for characterization of crystalline structure of Fe3O4/CuO nanocomposites. Scherrer's formula; D= 0.9λ/ß cosθ was employed for calculating the average crystallite size where D is the diameter of the nanoparticles, λ (CuKα) =1.5406 Å and ß is the fullwidth at half-maximum of the diffraction lines. A general way to prepare of compounds 5 The trichloroacetonitrile 1 (2 mmol) and amides 2 (2 mmol) mixed with ZnO-NPs (10 mol%) in water (5 mL). after 45 min amino acids 3 (2 mmol) was added to previous mixture at room temperature. After 30 min α-haloketones 4 (2 mmol) was added to mixture and stirred for 3 h. After 3 h, the reaction is completed and TLC confirms progress of the reaction. At last, the solid residue was collected by filtration and cleaned with EtOAC to removing ZnO-NPs and after evaporating solvent and washing solid with Et2O compounds 5 afforded as pure product. RESULTS: Without employing catalyst, these reactions have low yield and busy mixture. The synthesis of compound 5a as sample reaction and displayed the ZnO nanoparticles (10 mol%) is the best catalyst for sample reaction and H2O is the very better than other solvent in sample raection. Structures of 5 are confirmed by IR, 1H NMR, 13C NMR mass spectra. CONCLUSION: In summary, imdazole derivatives were produced in excellent yield from the reaction of trichloroacetonitrile, amides, alkyl bromides and amino acids using ZnO-NPs in water at room temperature. In addition, the power of synthesized imidazole as antioxidant was determined by radical trapping of DPPH and power of reducing ferric analyzes. The tested imidazoles display good radical trapping of DPPH but exhibitted moderate FRAP relative to BHT and TBHQ as synthetic antioxidants.The outcomes of disk diffusion experiment exhibite that synthesized imidazole avoided the bacterial growth. The superiorities of this procedure are environmental, high yield of product and low amounts of catalyst and short time of reaction.


Assuntos
Aminoácidos/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Imidazóis/farmacologia , Nanopartículas/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Antioxidantes/síntese química , Antioxidantes/química , Bacillus cereus/efeitos dos fármacos , Compostos de Bifenilo/antagonistas & inibidores , Catálise , Escherichia coli/efeitos dos fármacos , Imidazóis/síntese química , Imidazóis/química , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Picratos/antagonistas & inibidores , Staphylococcus aureus/efeitos dos fármacos
3.
Carbohydr Polym ; 222: 114982, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320096

RESUMO

Polysaccharides as natural hydrogels provide a promising strategy to prepare stimuli responsive drug carriers in pharmaceutical industries. In this work, Fe3O4 magnetic nanoparticles (MNPs) functionalized with (3-amino propyl) triethoxy silane (APTES) and coated by Chitosan (CS) and Tragacanth Gum (TG) to encapsulate curcumin. The synthesized nanocomposite was characterized using FT-IR, FE-SEM, EDX and XRD analysis. Taguchi Method (L9) with 3 levels and 4 variables was used to optimize the effect of concentration of Fe3O4@APTES, TG: CS ratio, nanocomposite weight, and curcumin weight on the drug loading. The release behaviour of curcumin was further studied in two different pH 7.4 and 3.4 and at temperatures 37 °C and 40 °C. The nanocomposite showed a higher swelling ratio at pH 3.4 and temperature 40 °C with good pH and thermosensitive in vitro drug release profiles. The results indicate that the nanocomposite has a good potential for delivery of chemotherapeutic drugs.


Assuntos
Curcumina/administração & dosagem , Portadores de Fármacos/química , Hidrogéis/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Quitosana/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Silanos/química , Temperatura , Tragacanto/química
4.
ISRN Dent ; 2012: 657068, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22461991

RESUMO

Introduction. Systematic evaluation is an integral part of the organization and delivery of community oral health care programmes, ensuring the effectiveness of these community-based interventions. This study aimed to assess the knowledge and practice of primary health care (PHC) personnel regarding their duties toward oral health. Methods and Material. A cross-sectional study was carried out among three groups of PHC personnel in the city of Kerman (Iran). Volunteer personnel completed a piloted questionnaire which included demographic data, some question regarding their knowledge about oral health, their duties and also their practice regarding public oral health. All data were analyzed using chi-square and Pearson correlation test. Results. One hundred and fifty-seven out of 225 eligible personnel participated in the study. Sixty percent were auxiliary health workers (Behvarz). All personnel had a good level of knowledge regarding oral health. Despite significant differences among the knowledge of the personnel toward oral health, there was no significant difference between their knowledge related to their duties regarding oral health. The auxiliary health worker group had a higher rate (45.6%) for better public oral health practice. Conclusion. The study showed the personnel have good knowledge of their duties regarding oral health. However, their practice is not in line with their knowledge and needs more attention.

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