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1.
ACS Omega ; 8(49): 47239-47253, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107937

RESUMO

An efficient, microwave/ultrasound-irradiated synthesis of novel chromenopyrimidines has been established. 2-Amino-5-oxo-4-(thiophen-2-yl)-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (1) underwent cyclization reactions with various assorted reagents under sustainable conditions to afford a family of fused pyrimidine derivatives. The proposed structures of the designed fused pyrimidines were confirmed by several spectral techniques. Moreover, the targeted pyrimidines were estimated for their in vitro cytotoxic activities toward three carcinoma cell lines: breast (MCF7), hepatocyte (HepG2), and lung (A549) cancer cell lines, as well as one noncancerous cell line (MCF-10A). Structure-activity relationship (SAR) analyses revealed that derivatives 3 and 7 exhibited the highest potency in inhibiting the growth of cancer cells tested in vitro. Particularly, 3-amino-4-imino-5-(thiophen-2-yl)-3,4,5,7,8,9-hexahydro-6H-chromeno[2,3-d]pyrimidin-6-one (3) displayed a robust impact with IC50 values ranging from 2.02 to 1.61 µM. Interestingly, compound 3 was observed to have low cytotoxicity toward noncancerous cell (MCF-10A) compared to the standard drug (Doxorubicin). Further, quantum chemical computations of the designed molecules utilizing density functional theory (DFT) were conducted and shown to be compatible with the observed antiproliferative properties. Thorough docking investigations revealed that the assembled compounds possess exceptionally low binding energies toward our three selected proteins: 4b3z-Lung, HepG2-2JW2, and 6ENV-MCV-7. Based on these intriguing results, compound 3 could be further evaluated for preclinical screening, potentially paving the way for its utilization as a promising cancer treatment.

2.
Molecules ; 28(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37175282

RESUMO

In light of the variety of industrial uses and economic relevance of mild steel, corrosion resistance is a serious topic. Utilization of inhibitors serves as one of the most essential methods for corrosion control. Two thiadiazole compounds, namely, 2-amino-5-(4-bromobenzyl)-1,3,4-thiadiazole (a1) and 2-amino-5-(3-nitrophenyl)-1,3,4-thiadiazole (a2), were synthesized. The structure of the prepared compounds was verified by Fourier transform infrared spectroscopy (FTIR) and proton and carbon-13 nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR). In a 0.50 M H2SO4 solution, the effectiveness of two synthetic thiadiazole derivatives as mild steel corrosion inhibitors were investigated. In this evaluation, various electrochemical methodologies have been utilized, such as potentiodynamic polarization, open circuit potential (OCP), and electrochemical impedance spectroscopy (EIS). The results confirm the efficiency of the inhibition increases by raising concentrations of a1 and a2. The inhibitory behavior was explained by the notion that the adsorption of thiadiazole molecules, a1 and a2, on the surface of mild steel causes a blockage of charge and mass transfer, protecting the mild steel from offensive ions. Furthermore, the synthesized molecules a1 and a2 were analyzed using density functional theory (DFT).

3.
Molecules ; 27(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36500510

RESUMO

Methylene blue (MB) immobilized onto a sulfonated poly(glycidyl methacrylate) (SPGMA) polymer composite has been developed as a novel adsorbent for water treatment applications. The MB adsorptions onto sulfonated poly(glycidyl methacrylate) polymer characters have been studied. The adsorption isotherms, namely Langmuir and Freundlich, have been investigated. Other isotherm models. As a compromise between the Freundlich and Langmuir isotherm models, such as the D-R isotherm and the Temkin isotherm, have been compared. The results indicated that the adsorption process followed the Freundlich isotherm model, indicating heterogeneous surface site energies and multi-layer levels of sorption. This study selected three linear kinetic models, namely pseudo-first order, pseudo-second order, and Elovich, to describe the MB sorption process using SPGMA negatively charged nanoparticles (430 nm). The obtained data revealed that the adsorption process obeyed the pseudo-second-order kinetic model, suggesting that the rate-limiting step in these sorption processes may be chemisorption. Furthermore, the thermodynamic parameters have been evaluated. Moreover, the interaction of the MB molecules with SPGMA nanoparticles has been simulated using the governing equation that describes ion exchange resin derived from Nernst-Plank equations between two ion species. Finally, the developed MB-SPGMA composite adsorbent (27 mg/g) wastested for the first time for the removal of Cr6+ ions and Mn7+ metal ions from dichromate and permanganate-contaminated waters under mild adsorption conditions, opening a new field of multiuse of the same adsorbent in the removal of more than one contaminant.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Azul de Metileno , Compostos Azo , Polímeros , Concentração de Íons de Hidrogênio , Purificação da Água/métodos , Cinética , Adsorção , Termodinâmica , Alcanossulfonatos
4.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364462

RESUMO

The arsenic (As) pollution of water has been eliminated via intensive scientific efforts, with the purpose of giving safe drinking water to millions of people across the world. In this study, the adsorption of As(V) from a synthetic aqueous solution was verified using a Bentonite-Anthracite@Zetag (BT-An@Zetag) composite. The SEM, FT-IR, XRD, DSC, TGA, and SBET techniques were used to characterize the (BT-An@Zetag) composite. The adsorption of As(V) was explored using batch adsorption under varied operating scenarios. Five kinetic modelswere used to investigate kinetic data, whereas three isotherms had been used to fit empirical equilibrium data. According to the findings, the adsorption mechanism of As(V) was best described by the Freundlich isotherm with a maximum monolayer coverage of 38.6 mg/g showing pseudo-second-order mode. The estimated enthalpy (H°) indicates that the adsorption process is both chemical and endothermic.The calculated free energy (G°) indicates that the reaction is nonspontaneous. After four sequential adsorption cycles, the produced BT-An@Zetag composite demonstrated good reusability and a greater adsorption affinity for As(V) ions. Overall, the BT-An@Zetag composite is suited for removing arsenic from wastewater using adsorption as a cost-effective and efficient technique.


Assuntos
Arsênio , Quitosana , Poluentes Químicos da Água , Humanos , Bentonita/química , Carvão Mineral , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Quitosana/química , Adsorção , Água/química , Cinética , Termodinâmica , Concentração de Íons de Hidrogênio
5.
Polymers (Basel) ; 14(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36365665

RESUMO

Methylene blue azo dye (MB) immobilized onto Poly (glycidyl methacrylate-Co-methyl methacrylate), (PGMA-co-PMMA), and sulphonated Poly (glycidyl methacrylate-Co-methyl methacrylate), (SPGMA-co-PMMA), polymers composites have been developed as novel adsorbents for water treatment applications. The effect of copolymer composition and sulphonation on the MB content has been studied. Maximum MB content was correlated to the Polyglycidyl methacrylate content for both native and sulphonated copolymers. Furthermore, the effect of the adsorption conditions on the MB content was studied. Sulfonated Poly (glycidyl methacrylate; SPGMA) was the most efficient formed composite with the highest MB content. The developed composites' chemical structure and morphology were characterized using characterization tools such as particle size, FTIR, TGA, and SEM analyses. The developed MB-SPGMA composite adsorbent (27 mg/g), for the first time, was tested for the removal of Cr (VI) ions and Mn (VII) metal ions from dichromate and permanganate contaminated waters under mild adsorption conditions, opening a new field of multiuse of the same adsorbent in the removal of more than one contaminants.

6.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36145355

RESUMO

In this study new sulphamethoxazole derivatives (S1-S4, S6-S12, and S14-S22) were designed and synthesized and their structures were fully characterized and validated using NMR, mass, and IR spectroscopy, as well as elemental analyses. All new derivatives (S1-S22) were assayed against human carbonic anhydrase (hCAs IX and XII) for their inhibitory activities. hCAs IX and XII were chosen due to the fact that CAIX expression is recognized as a hypoxia marker with a poor prognosis in breast cancer. When compared to Dorzolamide HCl as a standard reference, derivatives S2, S3, S8, S9, and S15 had the most effective inhibition with low IC50 values. The active compounds were further evaluated against hCAs I and II inhibitory activity and compounds S8, S9 and S15 showed the least inhibitory effect compared to the reference standard, acetazolamide, indicating that their effect in normal cells is the lowest. Cell viability tests for the selected compounds were carried out on MCF7 (normoxia and hypoxia) and on the normal breast cell line (MCF10a) with Staurosporine as a standard. The results showed that compound S15 had a highly potent cytotoxic effect. Furthermore, cell cycle analysis results showed that compound S15 triggered cell cycle arrest and apoptosis in G1/S of MCF7 cancer cells. Finally, molecular docking was performed to point out the possible explanation for the vital structural features and key-interactions exerted by our ligands with hCAs IX and XII that might share additional designs and highlight possible leads for a hopeful anticancer agent. Consequently, sulphamethoxazole Derivative S15 could be the potential lead for emerging selective cytotoxic compounds directing h CAs IX and XII.

7.
ACS Omega ; 7(31): 27674-27689, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35967065

RESUMO

An efficient and environmentally friendly method was established for designing novel 3-amino-1,4-dihydroquinoxaline-2-carbonitrile (1) via the reaction of bromomalononitrile and benzene-1,2-diamine under microwave irradiation in an excellent yield (93%). This targeted amino derivative was utilized for the construction of a series of Schiff bases (8-13). A new series of thiazolidinone derivatives (15-20) were synthesized in high yields (89-96%) via treatment of thioglycolic acid with Schiff bases (8-13) under microwave irradiation in high yields (89-96%). Moreover, new pyrimidine derivatives (26-30 and 35-38) were prepared by treatment of compound 1 with arylidenes (21-25) and/or alkylidenemalononitriles (31-34) using piperidine as a basic catalyst under microwave conditions. Based on elemental analyses and spectral data, the structures of the new assembled compounds were determined. The newly synthesized quinoxaline derivatives were screened and studied as an insecticidal agent against Aphis craccivora. The obtained results indicate that compound 16 is the most toxicological agent against nymphs of cowpea aphids (Aphis craccivora) compared to the other synthesized pyrimidine and thiazolidinone derivatives. The molecular docking study of the new quinoxaline derivatives registered that compound 16 had the highest binding score (-10.54 kcal/mol) and the thiazolidinone moiety formed hydrogen bonds with Trp143.

8.
ACS Omega ; 7(33): 29142-29152, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36033712

RESUMO

A green synthetic approach and facile method was developed to produce pyrazole compounds (6a-d) by the reaction of ethyl acetoacetate (1), hydrazines (2a-d), and catalytic imidazole (3) in aqueous media. 4-Dicyanomethylene-2-pyrazoline-5-one derivatives (14a-d) were synthesized through the reaction of 2-pyrazoline-5-one derivatives (6a-d) with tetracyanoethylene (TCE) (7) by using catalytic imidazole (3) in an aqueous medium. Moreover, the 4-dicyanomethylene derivative (16) was obtained via treatment of 1-phenyl-3,5-pyrazolidinedione (15) with TCE (7). The spiropyrazoleoxirane derivatives (18 and 20) were prepared by treating the precursor 4-dicyanomethylene-2-pyrazoline-5-one derivative (14b) with hydrogen peroxide in various polar solvents under alkaline conditions. The spiropyrazole oxirane derivative (18) was used as a precursor for the design of functionalized pyrazolone derivatives (24 and 27a, b). The chemical structure of the novel designed derivatives was ascertained based on elemental analyses, mp, thin-layer chromatography, and spectral analyses. Furthermore, some of the synthesized derivatives were examined against different pathogenic bacterial and fungal strains. Their results demonstrated that some of them revealed notable antimicrobial activities.

9.
Plants (Basel) ; 11(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35890504

RESUMO

Origanum majoranum L. is a Lamiaceae medicinal plant with culinary and ethnomedical applications. Its biological and phytochemical profiles have been extensively researched. Accordingly, this study aimed to investigate the chemical composition and the antibacterial and antioxidant properties of O. majoranum high features, as well as to search for techniques for activity optimization. A metabolomics study of the crude extract of O. majoranum using liquid chromatography-high-resolution electrospray ionization mass spectrometry (LC ± HR ± ESI ± MS) was conducted. Five fractions (petroleum ether, dichloromethane, ethyl acetate, n-butanol, and aqueous) were derived from the total extract of the aerial parts. Different chromatographic methods and NMR analysis were utilized to purify and identify the isolated phenolics (high features). Moreover, the antimicrobial, antibiofilm, and antioxidant activity of phenolics were performed. Results showed that metabolomic profiling of the crude extract of O. majoranum aerial parts revealed the presence of a variety of phytochemicals, predominantly phenolics, resulting in the isolation and identification of seven high-feature compounds comprising two phenolic acids, rosmarinic and caffeic acids, one phenolic diterpene, 7-methoxyepirosmanol, in addition to four flavonoids, quercetin, hesperitin, hesperidin, and luteolin. On the other hand, 7-methoxyepirosmanol (OM1) displayed the most antimicrobial and antioxidant potential. Such a phenolic principal activity improvement seems to be established after loading on gold nanoparticles.

10.
ACS Omega ; 6(37): 23924-23933, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34568671

RESUMO

As a filler to be inserted into poly(vinyl chloride) (PVC), low-cost olive pits flour (OPF) and precipitated bio-calcium carbonate (PBCC)-produced PVC/OPF/PBCC composites have been used with high stability and rigidity compared to PVC. Hydrogen bonding is generated between OH cellulose in OPF and H in PVC. Composite tensile modulus increased in PVC grid in the presence of PBCC and OPF, possibly because of a filler restriction effect on the polymer chains. The hardness also increased as both OPF and PBCC increased. The mechanical tendency of the PVC/OPF composite was improved by adding a low content of PBCC particles with the PVC network, resulting in a smart distribution in the range of 10% by weight, and it was reduced by adding more than that percentage. The successful distribution of PBCC in PVC/OPF composite strengthened the mechanical path. The morphology and possible interface adhesion of components in the composite were demonstrated by scanning electron microscopy (SEM). The PVC SEM images showed a homogeneous, smart, and consistent surface, while the PVC/60 wt % OPF SEM images showed a large number of voids that suggested weak PVC/OPF interactions. The SEM images showed outstanding PBCC distribution in the PVC/OPF matrix for the PVC/50 wt % OPF/10 wt % PBCC composite. Due to the accumulation of PBCC particles producing cavities, the distribution of particles became nonhomogeneous at percentages above 10 wt %. At a low filler material, better spread of PBCC particles in the PVC grid was achieved. Owing to the polarity of OPF, the H2O absorption and thickness swelling of PVC/OPF/PBCC composites showed higher amounts than PVC. PBCC improved the thermal stabilization and the neutralization of Cl- negative ions as an acid acceptor of secondary PVC stabilization.

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