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1.
J Mol Graph Model ; 130: 108791, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38776762

RESUMEN

A novel series of alkaline earthides containing eight complexes based upon 36adz complexant are designed by placing carefully transition metals (V-Zn) on inner side and alkaline earth metal outer side of the complexant i.e., M+(36adz) Be- (M+ = V, Cr, Mn, Fe, Co, Ni, Cu and Zn). All the designed compounds are electronically and thermodynamically stable as evaluated by their interaction energy and vertical ionization potential respectively. Moreover, the true nature of alkaline earthides is verified through NBOs and FMO study, showing negative charge and excess electrons on alkaline earth metal respectively. Furthermore, true alkaline earthides characteristics are evaluated graphically by spectra of partial density state (PDOS). The energy gap (HOMO -LUMO gap) is very small (ranging 2.95 eV-1.89 eV), when it is compared with pure cage 36adz HOMO-LUMO gap i.e., 8.50 eV. All the complexes show a very small value of transition energy ranging from 1.68eV to 0.89eV. Also, these possess higher hyper polarizability values up to 2.8 x 105au (for Co+(36adz) Be-). Furthermore, an increase in hyper polarizability was observed by applying external electric field on complexes. The remarkable increase of 100fold in hyper polarizability of Zn+(36adz) Be- complex is determined after application of external electric field i.e., from 1.7 x 104 au to 1.7 x 106 au when complex is subjected to external electric field of 0.001 au strength. So, when external electric field is applied on complexes it enhances the charge transfer, polarizability and hyper polarizability of complexes and proves to be effective for designing of true alkaline earthides with remarkable NLO response.


Asunto(s)
Metales Alcalinotérreos , Metales Alcalinotérreos/química , Termodinámica , Modelos Moleculares , Complejos de Coordinación/química
2.
Front Chem ; 10: 1017577, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36438873

RESUMEN

Rondeletia odorata Jacquin is a flowering plant that belongs to the coffee family. As a rich source of polyphenols with significant antioxidant potential, R. odorata may have health benefits. Therefore, in the current work, ethanolic extract of aerial parts and its n-hexane, ethyl acetate, and n-butanol soluble fractions were analyzed for their antioxidant potential and various enzyme inhibition properties. The total phenolic and flavonoid contents of the crude ethanol extract (ROE) and its n-hexane (ROH), ethyl acetate (ROEA), and n-butanol (ROB) fractions were determined spectrophotometrically, while metabolic profiling was established through UHPLC-MS analysis, which revealed the presence of 58 phytochemicals. Total phenolic and flavonoid contents of ROE extract were measured as 51.92 mg GA.Eq./g of dry extract and 52.35 mg Qu.Eq./g of the dry extract, respectively. In the DPPH radical scavenging activity assay, ROE and ROEA showed the highest potential with values of 62.13 ± 0.62 and 76.31% ± 1.86%, respectively, comparable to quercetin (80.89% ± 0.54%). Similarly, in the FRAP assay, the same pattern of the activity was observed with ROE and ROEA, which displayed absorbance values of 1.32 ± 0.01 and 0.80 ± 0.02 at 700 nm, respectively, which are comparable (1.76 ± 0.02) with the reference compound quercetin, whereas the ROH showed maximum metal-chelating capacity (62.61% ± 1.01%) among all extracts and fractions. Antibacterial activity assay indicated that the ROEA fraction was the most active against Serratia marcescens, Stenotrophomonas maltophilia, Bacillus subtilis, Klebsiella pneumonia, and Staphylococcus aureus, while the rest of the fractions showed good to moderate activity. Enzyme inhibition assays showed that ROEA fraction exhibited the highest activity with IC50 values of 2.78 ± 0.42 and 3.95 ± 0.13 mg/mL against urease and carbonic anhydrase (CA), respectively. Furthermore, the docking studies of some of the major compounds identified in the extract revealed a strong correlation with their inhibitory activity. All extracts and fractions were also tested for their thrombolytic activity, and the ROB fraction showed a notable potential. Antiviral assay led to remarkable outcomes. Thus, it can be inferred that aerial parts of R. odorata are potential sources of bioactive components with several significant pharmacological activities.

3.
Int J Biomater ; 2022: 6585305, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36119660

RESUMEN

In this study, ternary blends based on chitosan, polyvinyl alcohol, and polyethylene glycol reinforced with organically modified montmorillonite (nanoclay) clay were synthesized. These ternary blends were evaluated as transdermal drug delivery patches using tramadol as a model drug. The FTIR study showed interaction among important functional groups and compatibility among the mixing components. Among drug-loaded formulations, composite MA12 shows maximum thermal stability with 27.9% weight residue at 540°C. The prepared formulations exhibited crystalline nature as observed by XRD analysis. SEM studies revealed that there are no gaps and cracks in prepared films and nanoclay was found dispersed in the formulations. The swelling ratio was higher in pH 1.2 as compared to pH 4.5 and pH 6.8 buffers, and there was an increase in swelling with an increase in PVA concentration. Moreover, the drug release test performed in phosphate buffer pH 6.8 showed that tramadol release from nanocomposite films increases with an increase in PEG concentration. Permeation studies indicated that the rate of permeation increased with a decrease in PVA concentration. The permeation rate was found to be higher for samples without nanoclay. The overall results suggest nanocomposite films as excellent candidates for transdermal drug delivery application.

4.
ACS Omega ; 7(19): 16716-16727, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35601321

RESUMEN

End-capped modification is an efficient approach for enhancing the power conversion efficiency of organic solar cells (OSCs). Herein, five novel acceptor molecules have been designed by end-capper modification of the recently synthesized molecule NTIC (R). Different geometric and photovoltaic properties like frontier molecular orbital analysis, absorption maximum, transition density matrix analysis, reorganizational energy, binding energy, oscillator strength, energy of excitation, and charge transfer analysis of designed and reference molecules have been computed by employing density functional theory and time-dependent density functional theory. Designed molecules expressed a narrow energy band gap (E g) with red-shifting in the absorption spectrum. Additionally, low excitation and binding energies are also noted in designed molecules. Excellent values of hole and electron reorganizational energies suggested that designed molecules are effective contributors to the development of the active layer of the organic solar cells. Further, a complex study is also performed for evaluation of charge transfer between the acceptor molecule and the donor polymer. Results of all analyses recommended that designed molecules are effective candidates for high-performance organic solar cell applications.

6.
J Mol Model ; 28(3): 67, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35201436

RESUMEN

Organic solar cells (OSCs) with bulk heterojunction (BHJ) structures consisting of electron-donor and electron-acceptor materials have achieved impressive progress over the past decade, demonstrating their great potential in practical applications. In this study, we have designed five fullerene-free acceptor-based molecules containing indaceno-dithiophene as a central core moiety. We studied the optoelectronic features of these newly architecture molecules by using DFT and TD-DFT approaches. For the investigation of the optoelectronic characteristics of the reference and newly designed molecules, we performed different parameters including FMO's, absorption maxima, excitation energy, transition density matrix (TDM) along with binding energy, dipole moment, the partial density of states, charge mobility, and charge transfer analysis. Among all engineered molecules, SK1 has proven to be the most efficient solar cell due to its promising optoelectronic and photovoltaic properties. SK1 reveals smaller band-gap (Egap = 1.959 eV) and lesser λh (0.0070 eV) and λe (0.0051 eV). SK1 illustrated comparable binding energy value (0.33 eV) and lowest excitation energy (1.62 eV) which will lead to improved power conversion efficiency values. The SK1 molecule demonstrated the highest λmax value (764 nm) in the solvent phase which could lead to redshift absorption for achieving the high efficiency of OSCs. This molecular modeling approves that the best working efficiency of organic solar devices can be achieved by terminal group modifications due to their promising photovoltaic and optoelectronic properties. It is evident from the current analysis that all the theoretically fabricated molecules (SK1-SK5) are fabulous and highly suggested to experimental workers for their synthesis and advancement of these highly competent solar devices in the future.

7.
Curr Org Synth ; 18(6): 592-597, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-33441077

RESUMEN

AIMS: The aim of the present research was to synthesize glycoluril derivative 2,4-Bis(4- cyanobenzyl)glycoluril through a convergent scheme. BACKGROUND: For this purpose, Sandmeyer reaction procedure was employed for the synthesis of said compound. The structure of the pure compound was confirmed by using different spectroscopic techniques, such as 1HNMR, 13C-NMR and (HR-MS) Mass spectrometry. OBJECTIVE: Convergent synthesis of 2,4-BIS (4-CYANOBENZYL)GLYCOLURIL USING SANDMEYER REACTION and urease inhibition study. METHODS: The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. The electronic properties of the newly synthesized compound and thiourea were determined by using density functional theory. RESULTS: Furthermore, the compound was evaluated against urease enzyme and was found to be potent inhibitors with an IC50 value of 11.5 ± 1.50 µM when compared with standard inhibitor thiourea (IC50 = 21.0 ± 1.90 µM). The compound may serve as a lead compound to synthesize new cyano-based bambusuril in the future with enhanced biological properties. CONCLUSION: We have synthesized a new glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril by the sandmeyer reaction. It has been obtained in the form of light yellowish powder in good yield (96%). Glycoluril based macrocycles have been used in various fields; starting from the 2,4-Bis(4-nitrobenzyl)glycoluril (already reported compound), which has undergone reduction (CH3OH,Pt/C) , diazotization (NaNO2/HCl), cyanation (CuCl/KCN), respectively in order to synthesize the desired new glycoluril derivative. The obtained product will be used as a building block for the synthesis of the cyano based bambusuril marcocycle in the future. The yield of the obtained product has been monitored by using different amounts of cyanating reagent, but the best results are shown by the use of 4 mmol of CuCl/KCN. KCN with CuCl assisted the conversion of diazo group into the cyano group with enhanced yield when used in excess amount. It acts as a catalyst. The solubility characteristic of 2,4-Bis(4-cyanobenzyl)glycoluril has also been determined in different organic solvents. 1H NMR technique proved to be very helpful for the structure determination of our desired product. Benzylic protons give signals at 7.5 ppm and 7.8 ppm, respectively. The downfield peaks confirm the presence of CN group near the benzylic protons. Methine protons show a signal at 5.2 ppm, which ensures the basic skeleton of glycoluril. Ureidyl protons also confirm the synthesis of the heterocyclic 2,4-Bis(4-cyanobenzyl)glycoluril compound. The negative and positive electrostatic potential sites, molecular descriptors, and charge density distribution of frontier molecular orbitals are revealing that 4a with promising sites for electrophilic and nucleophilic attacks would result to enhance the urease inhibition, which is in good agreement with the experimental data.


Asunto(s)
Inhibidores Enzimáticos , Ureasa , Teoría Funcional de la Densidad , Inhibidores Enzimáticos/farmacología , Imidazoles , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Ureasa/metabolismo
8.
Chem Commun (Camb) ; 51(22): 4666-9, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25690137

RESUMEN

Bambusuril-based receptors have been used in conjunction with (1)H NMR spectroscopy to recognize mixtures of inorganic anions in aqueous solutions. This was achieved by examining complexation-induced changes in the receptors' (1)H NMR fingerprints. This approach enables the simultaneous identification of up to 9 anions and the quantification of up to 5 anions using a single receptor in DMSO-d6 containing 5% D2O. Toxic perchlorate was recognized and quantified at 0.1 µM (1.8 ppb, mol mol(-1)) concentration in pure water.


Asunto(s)
Imidazoles/química , Compuestos Macrocíclicos/química , Aniones/análisis , Espectroscopía de Resonancia Magnética , Conformación Molecular , Protones , Soluciones , Factores de Tiempo , Agua/química
9.
Angew Chem Int Ed Engl ; 54(1): 276-9, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25385515

RESUMEN

Synthetic receptors that function in water are important for the qualitative and quantitative detection of anions, which may act as pollutants in the environment or play important roles in biological processes. Neutral receptors are particularly appealing because they are often more selective than positively charged receptors; however, their affinity towards anions in pure water is only in range of 1-10(3)  L mol(-1) . The anion-templated synthesis of a water-soluble bambusuril derivative is shown to be an outstanding receptor for various inorganic anions in pure water, with association constants of up to 10(7)  L mol(-1) . Furthermore, the macrocycle discriminates between anions with unprecedented selectivity (up to 500 000-fold). We anticipate that the combination of remarkable affinity and selectivity of this macrocycle will enable the efficient detection and isolation of diverse anions in aqueous solutions, which is not possible with current supramolecular systems.


Asunto(s)
Aniones/aislamiento & purificación , Imidazoles/química , Compuestos Macrocíclicos/química , Agua/análisis , Aniones/análisis , Sitios de Unión , Imidazoles/síntesis química , Compuestos Macrocíclicos/síntesis química , Modelos Moleculares
10.
Org Biomol Chem ; 6(19): 3542-51, 2008 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-19082155

RESUMEN

6-(Thien-2-yl) and 6-(fur-2-yl)salicylates are prepared by TiCl(4)-mediated [3 + 3] cyclocondensations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-(thien-2-yl)- and 3-(fur-2-yl)-3-silyloxy-2-en-1-ones, respectively. The regioselectivity of the cyclization depends on the substitution pattern of the 3-silyloxy-2-en-1-one.


Asunto(s)
Butadienos/química , Salicilatos/síntesis química , Cristalografía por Rayos X , Ciclización , Salicilatos/química , Estereoisomerismo , Especificidad por Sustrato
12.
J Org Chem ; 72(16): 6255-8, 2007 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-17604399

RESUMEN

Functionalized dibenzo[b,d]pyran-6-ones were prepared by formal [3 + 3] cyclization of 1,3-bis(silyl enol ethers) with 3-silyloxy-2-en-1-ones or 1,1-diacetylcyclopropane to give functionalized salicylates, Suzuki cross-coupling reactions of the corresponding triflates, and subsequent BBr3-mediated lactonization. A second approach to dibenzo[b,d]pyran-6-ones relies on the [3 + 3] cyclization of 1,3-bis(silyl enol ethers) with 1-(2-methoxyphenyl)-1-(trimethylsilyloxy)alk-1-en-3-ones and subsequent BBr3-mediated lactonization.


Asunto(s)
Química Orgánica/métodos , Piranos/química , Silanos/química , Benzoatos/química , Éteres/química , Modelos Químicos , Conformación Molecular , Oxígeno/química , Piranos/síntesis química , Salicilatos/química
13.
Chem Biodivers ; 4(7): 1578-85, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17638339

RESUMEN

Calligonolides A (1) and B (2), two new butanolides, and a new steroidal ester, 3, have been isolated from the whole plant of Calligonum polygonoides, together with four known compounds, tetracosan-4-olide, beta-sitosterol and its glucoside, and ursolic acid. Their structures were elucidated by spectroscopic and mass-spectrometric studies. Compounds 1-3 showed moderate inhibitory potential against lipoxygenase from soybean.


Asunto(s)
Inhibidores de la Lipooxigenasa/aislamiento & purificación , Lipooxigenasa/metabolismo , Polygonaceae/enzimología , Inhibidores de la Lipooxigenasa/química , Inhibidores de la Lipooxigenasa/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología
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