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1.
PLoS One ; 19(3): e0299364, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38551992

RESUMO

The purpose of this study is to examine the possibility of GO to be used as an adsorbent for five novel potentially hazardous azo-dyes for their removal from aqueous solution. Adsorption characteristics of GO for azo-dyes removal were investigated by means of experimental and computational DFT as well as Monte Carlo approaches. Experimental studies include the effect of adsorbent dose, contact time, and initial concentration, while computational investigation involves DFT and Monte Carlo (MC) simulations. Through DFT studies geometric, electronic, and thermodynamic parameters were explored and possible mechanism of interactions and adsorption energies by predicted through MC by searching lowest possible adsorption complexes. Experimental data were evaluated by Langmuir models in order to describe the equilibrium isotherms. Equilibrium data fitted well to the Langmuir model. Thermodynamic parameters i.e., free energy change, enthalpy change, and entropy change revealed that the removal of azo-dyes by adsorption on the surface of GO molecular sieves was spontaneous. Nature of the process was found to be physiosorption involving non-covalent interaction. The study unveiled that GO can be used as an efficient adsorbent material for the adsorption of azo-dyes from aqueous solution.


Assuntos
Compostos Azo , Poluentes Químicos da Água , Adsorção , Cinética , Termodinâmica , Indicadores e Reagentes , Água , Corantes , Concentração de Íons de Hidrogênio
2.
Int J Biol Macromol ; 263(Pt 1): 130231, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368975

RESUMO

Three newly synthesized amantadine thiourea conjugates namely MS-1 N-(((3 s,5 s,7 s)-adamantan-1-yl)carbamothioyl)benzamide, MS-2 N-(((3 s,5 s,7 s)-adamantan-1-yl)carbamothioyl)-4-methylbenzamide and MS-3 N-((3 s,5 s,7 s)-adamantan-1-ylcarbamothioyl)-4-chlorobenzamide were investigated for their structures, bindings (DNA/ elastase), and for their impact on healthy and cancerous cells. Theoretical (DFT/docking) and experimental {UV-visible (UV-), fluorescence (Flu-), and cyclic voltammetry (CV)} studies indicated binding interactions of each conjugate with DNA and elastase enzyme. Theoretically and experimentally calculated binding parameters for conjugate - DNA interaction revealed MS-3 - DNA to have most significant binding with comparatively greater values of binding parameters {(Kb/M-1: docking, 3.8 × 105; UV-, 5.95 × 103; Flu-,1.55 × 105; CV, 1.52 × 104), (∆G/ kJmol-1: docking, -32.09; UV-, -22.40; Flu-,-30.81; CV, -24.82)}. The docked structures, greater bindings site size values (n), and the trend in DNA viscosity changes in the presence of each conjugate concentration confirmed a mixed binding mode of interaction among them. Conjugate - elastase binding by docking agreed with the experimental anti-elastase findings. Cytotoxicity studies of each tested conjugate demonstrated greater cytotoxicity for cancerous (MG-U87) cells in comparison to control, while for the normal (HEK-293) cells the cytotoxicity was found comparatively low. Overall exploration suggested that MS-3 is the most effective candidate for DNA binding, anti-elastase, and for anti-glioma activities.


Assuntos
Amantadina , Tioureia , Humanos , Tioureia/farmacologia , Tioureia/química , Células HEK293 , Simulação de Acoplamento Molecular , Amantadina/farmacologia , DNA/química , Elastase Pancreática
3.
Molecules ; 29(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38257232

RESUMO

Additive manufacturing (AM), commonly referred to as 3D printing, has revolutionized the manufacturing landscape by enabling the intricate layer-by-layer construction of three-dimensional objects. In contrast to traditional methods relying on molds and tools, AM provides the flexibility to fabricate diverse components directly from digital models without the need for physical alterations to machinery. Four-dimensional printing is a revolutionary extension of 3D printing that introduces the dimension of time, enabling dynamic transformations in printed structures over predetermined periods. This comprehensive review focuses on polymeric materials in 3D printing, exploring their versatile processing capabilities, environmental adaptability, and applications across thermoplastics, thermosetting materials, elastomers, polymer composites, shape memory polymers (SMPs), including liquid crystal elastomer (LCE), and self-healing polymers for 4D printing. This review also examines recent advancements in microvascular and encapsulation self-healing mechanisms, explores the potential of supramolecular polymers, and highlights the latest progress in hybrid printing using polymer-metal and polymer-ceramic composites. Finally, this paper offers insights into potential challenges faced in the additive manufacturing of polymer composites and suggests avenues for future research in this dynamic and rapidly evolving field.

4.
RSC Adv ; 13(49): 34497-34509, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38024971

RESUMO

The reduction of nitrogen oxides (NOx) to NH3, or N2 represents a crucial step in mitigating atmospheric NO3 and NO2 emissions, a significant contributor to air pollution. Among these reduction products, ammonia (NH3) holds particular significance due to its utility in nitrogen-based fertilizers and its versatile applications in various industrial processes. Platinum-based catalysts have exhibited promise in enhancing the rate and selectivity of these reduction reactions. In this study, we employ density functional theory (DFT) calculations to explore the catalytic potential of Pt nanoparticle (PtNP)-supported ZrO2 for the conversion of NO3 to NH3. The most favorable pathway for the NO3 reduction to NH3 follows a sequence, that is, NO3 → NO2 → NO → ONH → ONH2/HNOH → NH2/NH → NH2 → NH3, culminating in the production of valuable ammonia. The introduction of low-state Fe and Co dopants into the ZrO2 support reduces energy barriers for the most challenging rate-determining hydrogenation step in NOx reduction to NH3, demonstrating significant improvements in catalytic activity. The incorporation of dopants into the ZrO2 support results in a depletion of electron density within the Pt cocatalyst resulting in enhanced hydrogen transfer efficiency during the hydrogenation process. This study aims to provide insights into the catalytic activity of platinum-based ZrO2 catalysts and will help design new high-performance catalysts for the reduction of atmospheric pollutants and for energy applications.

5.
J Mol Model ; 29(10): 305, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37670084

RESUMO

CONTEXT: Adsorption of 1 and 2 H2O molecules for hydrogen production and storage on the surface of pristine, carbamic acid and 2-amino 3-acetylpyridine functionalized SWCNTs with the dimensionality of (2, 4), (5, 5), and (6, 0) at various positions, i.e., center and edges were investigated by using computational DFT calculations. Adsorption energies and structural and electronic parameters were determined for pristine and functionalized SWCNTs with four different H2O orientations. Functionalization of 2-amino 3-acetylpyridine resulted in more favorable adsorption energies for 1 and 2 H2O molecules splitting as compared to spitting on pristine and carbamic acid functionalized SWCNT. Calculated adsorption constant, Kad confirmed greater binding interactions of functionalized SWCNTs with 1 and 2 H2O molecules as compared to pristine SWCNT. Isosurface for the adsorption of 1 and 2 H2O molecules on pristine and functionalized SWCNTs elaborated altered electrophilic and nucleophilic character. Effect of H2O concentration was monitored to determine hydrogen storage capacity which was found to be 7.17 wt.% for thirty molecules. An important finding of study is production of Stone-Wales (SW) defect upon H2O adsorption leading to increase in hydrogen production and its storage capacity. The functionalization of topological defected SWCNTs provides distinctive applications of CNTs for gas storage purposes.t: METHODS: In the current study, First Principal Density Functional Theory (DFT) calculations were carried which provides greater computational efficiency as compared to many traditional quantum mechanical methods. SCME: ADF (2018) modeling suite software with in framework of DFT approach using exchange correlation (XC) LDA-GGA (Generalized Gradient Approximation) with PBE (Perdew, Burke and Ernzerhof) functional and DZ (Double beta) basis set was employed to investigate structural, energetic and electronic aspects of adsorption on the surface of pristine, carbamic acid and 2-amino 3-acetly pyridine functionalized SWCNTs. (2, 4), (5, 5) and (6, 0) SWCNTs were designed using Avogadro's software and were imported to SCM: ADF graphical interface and were optimized as adsorbent. Single point energy (SPE), geometry optimization and high accuracy frequency calculations were performed to determine energetic, electronic and thermodynamic characteristics and feasibility of adsorption using XC of GGA-PBE functional & DZ basis set.

6.
RSC Adv ; 13(18): 11982-11999, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37077261

RESUMO

Two novel benzimidazole ligands (E)-2-((4-(1H-benzo[d]imidazole-2-yl)phenylimino)methyl)-6-bromo-4-chlorophenol (L1) and (E)-1-((4-(1H-benzo[d]imidazole-2-yl)phenylimino)methyl)naphthalene-2-ol (L2) with their corresponding Cu(ii), Ni(ii), Pd(ii) and Zn(ii) complexes were designed and synthesized. The compounds were characterized by elemental, IR, and NMR (1H & 13C) spectral analyses. Molecular masses were determined by ESI-mass spectrometry, and the structure of ligand L1 was confirmed by single crystal X-ray diffraction analysis. Molecular docking was carried out for the theoretical investigation of DNA binding interactions. The results obtained were verified experimentally by UV/Visible absorption spectroscopy in conjunction with DNA thermal denaturation studies. It was observed that ligands (L1 and L2) and complexes (1-8) were moderate to strong DNA binders, as evident from the binding constants (K b). The value was found to be highest for complex 2 (3.27 × 105 M-1) and lowest for 5 (6.40 × 103 M-1). A cell line study revealed that breast cancer cells were less viable to the synthesized compounds compared to that of standard drugs, cisplatin and doxorubicin, at the same concentration. The compounds were also screened for in vitro antibacterial activity for which complex 2 showed a promising broad-spectrum effect against all tested strains of bacteria, almost in the proximity of the reference drug kanamycin, while the rest of the compounds displayed activity against selected strains.

7.
Molecules ; 28(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36985680

RESUMO

Bis-acyl-thiourea derivatives, namely N,N'-(((4-nitro-1,2-phenylene)bis(azanediyl)) bis(carbonothioyl))bis(2,4-dichlorobenzamide) (UP-1), N,N'-(((4-nitro-1,2-phenylene) bis(azanediyl))bis(carbonothioyl))diheptanamide (UP-2), and N,N'-(((4-nitro-1,2-phenylene)bis(azanediyl))bis(carbonothioyl))dibutannamide (UP-3), were synthesized in two steps. The structural characterization of the derivatives was carried out by FTIR, 1H-NMR, and 13C-NMR, and then their DNA binding, anti-urease, and anticancer activities were explored. Both theoretical and experimental results, as obtained by density functional theory, molecular docking, UV-visible spectroscopy, fluorescence (Flu-)spectroscopy, cyclic voltammetry (CV), and viscometry, pointed towards compounds' interactions with DNA. However, the values of binding constant (Kb), binding site size (n), and negative Gibbs free energy change (ΔG) (as evaluated by docking, UV-vis, Flu-, and CV) indicated that all the derivatives exhibited binding interactions with the DNA in the order UP-3 > UP-2 > UP-1. The experimental findings from spectral and electrochemical analysis complemented each other and supported the theoretical analysis. The lower diffusion coefficient (Do) values, as obtained from CV responses of each compound after DNA addition at various scan rates, further confirmed the formation of a bulky compound-DNA complex that caused slow diffusion. The mixed binding mode of interaction as seen in docking was further verified by changes in DNA viscosity with varying compound concentrations. All compounds showed strong anti-urease activity, whereas UP-1 was found to have comparatively better inhibitory efficiency, with an IC50 value of 1.55 ± 0.0288 µM. The dose-dependent cytotoxicity of the synthesized derivatives against glioblastoma MG-U87 cells (a human brain cancer cell line) followed by HEK-293 cells (a normal human embryonic kidney cell line) indicated that UP-1 and UP-3 have greater cytotoxicity against both cancerous and healthy cell lines at 400 µM. However, dose-dependent responses of UP-2 showed cytotoxicity against cancerous cells, while it showed no cytotoxicity on the healthy cell line at a low concentration range of 40-120 µM.


Assuntos
Neoplasias Encefálicas , Urease , Humanos , Simulação de Acoplamento Molecular , Células HEK293 , Antibacterianos/farmacologia , DNA/química , Tioureia/química , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia
8.
ACS Omega ; 8(1): 333-345, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643508

RESUMO

Herein, a novel and environmentally benign solid catalyst was fabricated by grafting WO3 active species onto the ZnCo2O4@CeO2 support for efficient levulinic acid production from corncob waste biomass. The morphological, compositional, and textural properties of the designed catalyst were investigated using different characterization techniques to identify suitable catalyst formulation with enhanced catalytic activity and stability. The results demonstrated that WO3 active species were successfully loaded with uniform distribution onto the support to develop a robust catalyst with both acidic and basic sites. The experimental investigation showed that among the catalysts, WO3(10 wt %)/ZnCo2O4@CeO2 exhibited the best catalytic activity, providing a maximum levulinic acid yield of 78.49% at the optimal conditions of 6 wt % catalyst dosage, reaction temperature of 180 °C, and reaction time of 200 min. The presence of an optimum number of both acid and base active sites on the catalyst surface could lead to the highest catalytic activity of the synthesized catalyst. Finally, the reusability investigation indicated that the synthesized catalyst possessed sufficient recyclability of up to four times for the levulinic acid production from the selected biomass with negligible drop in the catalytic activity.

9.
Materials (Basel) ; 15(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36431459

RESUMO

The slow solvent evaporation approach was used to create a single crystal of (C7H6N3O2)2[ZnCl4] at room temperature. Our compound has been investigated by single-crystal XRD which declares that the complex crystallizes in the monoclinic crystallographic system with the P21/c as a space group. The molecular arrangement of the compound can be described by slightly distorted tetrahedral ZnCl42- anionic entities and 5-nitrobenzimidazolium as cations, linked together by different non-covalent interaction types (H-bonds, Cl…Cl, π…π and C-H…π). Hirshfeld's surface study allows us to identify that the dominant contacts in the crystal building are H…Cl/Cl…H contacts (37.3%). FT-IR method was used to identify the different groups in (C7H6N3O2)2[ZnCl4]. Furthermore, impedance spectroscopy analysis in 393 ≤ T ≤ 438 K shows that the temperature dependence of DC conductivity follows Arrhenius' law. The frequency-temperature dependence of AC conductivity for the studied sample shows one region (Ea = 2.75 eV). In order to determine modes of interactions of compound with double stranded DNA, molecular docking simulations were performed at molecular level.

10.
Heliyon ; 8(8): e10098, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36046526

RESUMO

Various N- and S-containing 5-membered heterocycles such as imidazole-2-thiones, thiazolidinones and thiazolidin-2-imines are among the most eminent biologically active organic heterocycles and are present in many marketed drugs. In view of their synthetic and biological significance, an efficient synthesis of two novel thiazolidine-2-imines (4a-b) utilizing a three-component one-pot approach starting from an aldimine, an alkyne and isothiocyanates has been developed. The reaction proceeded via a 5-exo digonal (5-exo dig) cyclization of a propargyl thiourea, formed in situ in the presence of Zn(II)-catalyst. The structures of the resulting products are elucidated by spectroscopic methods and X-ray crystallography. A DFT study explored the structural, thermodynamic and molecular electrostatic potential parameters for the compounds. The newly synthesized compounds (4a & 4b) were evaluated for the inhibition of tyrosinase both in vitro and in silico. The in vitro results revealed that the synthesized thiazolidine-2-imines (4a-b) showed good inhibition activity towards mushroom tyrosinase (IC50 = 1.151 ± 1.25 and 2.079 ± 0.87 µM respectively) in comparison to the kojic acid standard (IC50 = 16.031 ± 1.27 µM) a commonly used anti-pigment agent in plant and animal tissues. The experimental inhibition was further assessed by molecular docking studies between synthesized ligands and the human tyrosinase protein complex to investigate the intermolecular interactions responsible for tyrosinase inhibition activity.

11.
J Pak Med Assoc ; 72(7): 1391-1395, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36156566

RESUMO

OBJECTIVE: To determine clinical characteristics, obstetrics and perinatal outcome of coronavirus disease 2019 infection in pregnant women. METHODS: The cross-sectional study was conducted at the Department of Obstetrics and Gynaecology of the Ruth Pfau Civil Hospital, Karachi, and Dow University of Health Sciences, Karachi, from August 2020 to July 2021, and comprised pregnant women with suspicion of coronavirus disease 2019 infection, who underwent recommended testing, and were found to be positive. Oral swabs for the presence of infection were also taken from the neonate within 24 hours of delivery. Data was analysed using Stata 11. RESULTS: There were 41 women with a mean age of 27±5 years, a mean gestational age of 35±3 weeks, and mean parity 1.2±1.01. Of them, 3(7.3%) women died. Medical complications found along with coronavirus disease 2019 infection were pregnancy-induced hypertension 2(4.8%), eclampsia 4(11%) and diabetes mellitus 2(4.8%). Fever was the most common symptom seen in 12(30%) women, followed by cough 7(20%) and shortness of breath 6(14%). Majority 32(82%) of the women underwent caesarean section. The most common maternal complication was postpartum haemorrhage 6(20%). Also, 36(86%) women required intensive care unit stay for a mean 5±9 days. CONCLUSIONS: Fever, followed by cough and breathlessness, were the most common clinical features. Most common maternal and foetal complication was postpartum haemorrhage and low birth weight, respectively.


Assuntos
COVID-19 , Hemorragia Pós-Parto , Adulto , Cesárea , Tosse , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez , Gestantes , Adulto Jovem
12.
RSC Adv ; 12(27): 17596-17606, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35765454

RESUMO

Purinergic signaling is regulated by a group of extracellular enzymes called ectonucleotidases. One of its members i.e., ecto-5'-nucleotidase (h-e5'NT) is involved in the final step of the enzymatic hydrolysis cascade that is the conversion of adenosine monophosphate (AMP) to adenosine and therefore, involves the regulation of adenosine level in extracellular space. The overexpression of h-e5'NT has been observed in various pathological conditions such as hypoxia, inflammation and cancers, and led to various complications. Hence, the identification of a potent as well as selective inhibitor of h-e5'NT is of greater importance in therapeutic treatment of various diseases. Azomethine-thioxoimidazolidinone derivatives were studied for their inhibition potential against e5'NT enzyme along with cytotoxic potential against cancer cell lines possessing overexpression of e5'NT enzyme. The derivative (E)-3-((4-((3-methoxybenzyl)oxy)benzylidene)amino)-2-thioxoimidazolidin-4-one (4g) displayed selective and significant inhibition towards h-e5'NT with an IC50 value of 0.23 ± 0.08 µM. While two other derivatives i.e., (E)-3-(((5-bromothiophen-2-yl)methylene)amino)-2-thioxoimidazolidin-4-one (4b) and 2-thioxo-3-((3,4,5-trimethoxybenzylidene)amino)imidazolidin-4-one (4e), exhibited non-selective potent inhibitory behavior against both human and rat enzymes. Moreover, these derivatives (4b, 4e and 4g) were further investigated for their effect on the expression of h-e5'NT using quantitative real time polymerase chain reaction. Additionally, molecular docking and DFT studies were also performed to determine the putative binding mode of potent inhibitors within the enzyme active site. HOMO, LUMO, ΔE, and molecular electrostatic potential maps were computed by DFT and the charge transfer regions within the molecules were identified to find out the regions for electrophilic and nucleophilic attack.

13.
Aust J Prim Health ; 28(4): 315-320, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35638126

RESUMO

BACKGROUND: To contribute to the World Health Organization's End TBStrategy, the active tuberculosis (TB) case-finding approach has been proven effective. METHODS: A total of 66 chest camps were organised for patients in 15 selected districts in Punjab, Pakistan, in 2017. A mixed-method process evaluation was conducted in four randomly selected districts to evaluate the use of chest camps for active TB case finding to reach the maximum number of people with TB and to assess the implementation outcomes, such as effectiveness, feasibility, fidelity, and costs. RESULTS: Results indicated that 1458 attendees visited 24 chest camps in four selected districts. Among attendees, 297 presumptive cases were found and smear-tested; and 34 of the smear-tested were diagnosed as smear-positive TB patients. The prevalence of smear-positive TB patients among the chest camp participants was found to be 2.3%. The findings from interviews showed that preparation of chest camp activities, especially the involvement of community leaders, was found to be effective in achieving the desired level of attendance. The respondents found attending the chest camps for TB symptoms feasible and acceptable. The chest camp costs approximately US$280, including the pre-camp mobilisation events, whereas the cost per TB-positive patient was found to be US$197.64. CONCLUSIONS: The higher number of attendees without TB symptoms, the low proportion of smear-negative case registrations; and relatively high unit cost (per patient detected) were the areas identified for further attention. The study supports the continuation of chest camp activity, with further attention required for quality and efficiency concerns.


Assuntos
Escarro , Tuberculose , Humanos , Paquistão/epidemiologia , Prevalência , Tuberculose/diagnóstico , Tuberculose/epidemiologia
14.
Molecules ; 27(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35056668

RESUMO

Imidazolidine and thiazolidine-based isatin derivatives (IST-01-04) were synthesized, characterized, and tested for their interactions with ds-DNA. Theoretical and experimental findings showed good compatibility and indicated compound-DNA binding by mixed mode of interactions. The evaluated binding parameters, i.e., binding constant (Kb), free energy change (ΔG), and binding site sizes (n), inferred comparatively greater and more spontaneous binding interactions of IST-02 and then IST-04 with the DNA, among all compounds tested under physiological pH and temperature (7.4, 37 °C). The cytotoxic activity of all compounds was assessed against HeLa (cervical carcinoma), MCF-7 (breast carcinoma), and HuH-7 (liver carcinoma), as well as normal HEK-293 (human embryonic kidney) cell lines. Among all compounds, IST-02 and 04 were found to be cytotoxic against HuH-7 cell lines with percentage cell toxicity of 75% and 66%, respectively, at 500 ng/µL dosage. Moreover, HEK-293 cells exhibit tolerance to the increasing drug concentration, suggesting these two compounds are less cytotoxic against normal cell lines compared to cancer cell lines. Hence, both DNA binding and cytotoxicity studies proved imidazolidine (IST-02) and thiazolidine (IST-04)-based isatin derivatives as potent anticancer drug candidates among which imidazolidine (IST-02) is comparatively the more promising.


Assuntos
Antineoplásicos/farmacologia , DNA/metabolismo , Imidazolidinas/química , Isatina/farmacologia , Neoplasias/tratamento farmacológico , Tiazolidinas/química , Antineoplásicos/química , Proliferação de Células , Células HeLa , Humanos , Isatina/química , Células MCF-7 , Estrutura Molecular , Neoplasias/patologia , Relação Estrutura-Atividade
15.
Med Chem ; 18(2): 199-208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34561991

RESUMO

BACKGROUND: Heterocyclic compounds display versatile biological applications, so the aim of this paper was to prepare biologically important heterocycles with enhanced bacterial resistance and to evaluate for their various structural features that are responsible for their biological properties. OBJECTIVE: The objective was to synthesize bacterial resistance compounds with enhanced antibacterial properties. METHODS: Ester moiety containing thiazole ring was converted into its hydrazide derivatives. These heterocyclic derivatives were cyclized into another ring oxadiazole; hence a hybrid ring system of two biologically active rings was prepared. RESULTS: All the synthesized compounds were characterized by spectroscopic techniques and were screened for their antibacterial potential; they possess significant antibacterial activities. CONCLUSION: New hybrid heterocyclic ring systems were synthesized by cyclization of hydrazide derivatives by adopting two step strategy in good yields. All the synthesized compounds were evaluated for their antioxidant activities; they showed moderate to significant activities. QSAR and Molecular docking studies were performed to determine the mode of interaction. Experimental and computational data is in accordance with the determined antibacterial activities.


Assuntos
Antibacterianos , Oxidiazóis , Antibacterianos/farmacologia , Benzamidas , Simulação de Acoplamento Molecular , Oxidiazóis/farmacologia , Tiazóis
16.
J Inorg Biochem ; 224: 111590, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34507110

RESUMO

The bidentate N-(1-Alkylpyridin-4(1H)-ylidene)amide (PYA) pro-ligands [H2LBn][Cl]2 (2), and [H2LMe][TfO]2 (3) were prepared by simple alkylation reactions of the known compound, N,N-di(pyridin-4-yl)oxalamide (H2L, 1). The Pd(II) complexes, [Pd(LBn)2][Cl]2 (4), [Pd(LMe)2][Cl][TfO] (5), Pd(LBn)Cl2 (6) and Pd(LMe)Cl2 (7) were synthesized through reactions between these pro-ligands and suitable Pd(II) substrates in the presence of base. The molecular structures of 3 and 6 were obtained by single crystal X-ray structure determinations. Studies of the experimental and computational DNA binding interactions of the compounds 1-7 revealed that overall 4 and 6 have the largest values for the binding parameters Kb and ΔGbo. The results showed a good correlation with the steric and electronic parameters obtained by quantitative structure activity relationship (QSAR) studies. In-vitro cytotoxicity studies against four different cell lines showed that the human breast cancer cell lines MCF-7, T47D and cervical cancer cell line HeLa had either higher or similar sensitivities towards 4, 6 and 2, respectively, compared to cisplatin. In general, the cytotoxicity of the compounds, represented by IC50 values, decreased in the order 4 > 6 > 2 > 5 > 3 > 1 > 7 in cancer cell lines. Apoptosis contributed significantly to the cytotoxic effects of these anticancer agents as evaluated by apoptosis studies.


Assuntos
Amidas/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Paládio/química , Compostos de Piridínio/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X/métodos , DNA/química , Células HeLa , Humanos , Ligantes , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
17.
Cureus ; 13(5): e15216, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34178535

RESUMO

Introduction Induction of labor (IOL) is characterized by stimulating contractions of the uterus just before the instantaneous onset of labor, with or without amniotomy. According to the recommendation of the World Health Organization (WHO), induction must only be carried out when there is a clear medical need for one and when potential benefits outweigh the expected harm that may be caused by it. The present study was to determine the frequency of fetomaternal outcomes among pregnant women subject to the induction of labor. Methods The present prospective cross-sectional study was conducted over a period of one year starting from June 17, 2018, to July 25, 2019, in the Department of Obstetrics and Gynecology Unit III, Civil Hospital Karachi. After institutional ethical committee approval, 302 pregnant women who were subject to induction of labor were enrolled using a non-probability consecutive sampling technique. Outcome variables, i.e., postpartum hemorrhage, mode of delivery, hospital stay more than seven days, birth asphyxia, Apgar score < 7 at five minutes, neonatal jaundice, and low birth weight were noted. IBM Statistical Package for Social Sciences (SPSS) Statistics for Windows, version 21.0 (IBM Corp., Armonk, NY) was used for data analysis. Results A total of 302 women with an average age range was 18-45 years with a mean age of 28.5 ± 4.47, body mass index (BMI) 29.83 ± 3.83, and mean gestational age was 37 ± 4.3. Almost 205 (67.9%) of the cases were booked. One hundred and eighty (59.6%) were nulliparas, 57(18.8%) had para-1, 43 (14.4%) had para-2, and 22 (7.14%) had par-3. When fetomaternal outcome among the pregnant women subject to induction of labor was observed, postpartum hemorrhage was observed in 55 (18.21%), hospital stay more than seven days was in 51 (17%), birth asphyxia was in 45 (14.9%), neonatal jaundice was in 53 (17.6%), low birth weight was in 15 (4.96%), Apgar score < 7 was in 48 (16%), 39 (13%) women underwent for C-section and 263 (87%) of the women delivered vaginally. Conclusion This study concludes that the induction of labor (IOL) is safe and reliable and less risk of adverse feto-maternal outcome is associated with pregnancies between 37 weeks and 42 weeks of gestation. The evidence regarding IOL prior to 37 weeks and beyond 42 weeks of gestation is inadequate to reach any conclusion.

18.
Bioorg Chem ; 109: 104707, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33639362

RESUMO

1-(adamantane-1-carbonyl-3-(1-naphthyl)) thiourea (C22H24N2OS (4), was synthesized by the reaction of freshly prepared adamantane-1-carbonyl chloride from corresponding acid (3) with ammonium thiocyanate in 1:1 M ratio in dry acetone to afford the adamantane-1-carbonyl isothiocyanate (2) in situ followed by treatment with 1-naphthyl amine (3). The structure was established by elemental analyses, FTIR, 1H, 13C NMR and mass spectroscopy. The molecular and crystal structure were determined by single crystal X-ray analysis. It belongs to triclinic system P - 1 space group with a = 6.7832(5) Å, b = 11.1810(8) Å, c = 13.6660(10) Å, α = 105.941(6)°, ß = 103.730(6)°, γ = 104.562(6)°, Z = 2, V = 910.82(11) Å3. The naphthyl group is almost planar. In the crystal structure, intermolecular CH···O hydrogen bonds link the molecules into centrosymmetric dimers, enclosing R22(14) ring motifs, while the intramolecular NH···O hydrogen bonds enclose S(6) ring motifs, in which they may be effective in the stabilization of the structure. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H … H (59.3%), H … C/C … H (19.8%) and H … S/S … H (10.1%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. DFT, molecular docking and urease inhibition studies revealed stability and electron withdrawing nature of 4 as compared to DNA base pairs and residues of urease. The DNA binding results from docking, UV- visible spectroscopy, and viscosity studies indicated significant binding of 4 with the DNA via intercalation and groove binding. Further investigation of the compound was done on hepatocellular carcinoma; Huh-7 cell line as well as normal human embryonic kidney; Hek-293 cell line. The compound showed significant cytotoxic activity against Huh-7 cells in comparison to normal Hek-293 cells indicating selective cytotoxicity towards cancer cells.


Assuntos
Adamantano/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Tioureia/análogos & derivados , Urease/metabolismo , Adamantano/síntese química , Adamantano/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular , Cristalografia por Raios X , DNA/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Tioureia/síntese química , Tioureia/química , Tioureia/farmacologia , Urease/genética
19.
J Biomol Struct Dyn ; 39(10): 3548-3564, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32397836

RESUMO

The work presented in this paper describes the synthesis of two new aryl Schiff bases [(E)-N-(4-(benzyloxy)-3-methoxybenzylidene)-5-(1-(4-isobutylphenyl)ethyl)-1,3,4-thiadiazol-2-amine] (ASB-1) and [(E)-N-(4-(benzyloxy)benzylidene)-5-(1-(4-isobutylphenyl)ethyl)-1,3,4-thiadiazol-2-amine] (ASB-2). These compounds were characterized by different analytical techniques and then studied for DNA binding. Binding studies were carried out at neutral pH (7.0) and at 37 °C by theoretical and experimental methods including DFT, molecular docking, spectroscopy (UV-visible, fluorescence), cyclic voltammetry (CV) and viscometry. Further investigations of these compounds were done on hepatocellular carcinoma; Huh-7 cancer cell line. Binding constant, free energy change and binding site size, i.e. Kb, ΔG and n were evaluated which indicated that both ASB-1 and ASB-2 bind significantly and spontaneously with the DNA. However, data revealed relatively greater binding of ASB-1 with DNA. Spectral and voltammetric results were found supportive of each other. Binding site sizes and viscosity measurements verified the mixed binding mode of interactions as observed in molecular docking analysis, i.e. intercalation with groove binding. DNA binding studies were very well correlated with the in-vitro studies performed on Huh-7 cell line as well as normal HEK-293 cell lines. The compound ASB-1 not only showed greater binding affinity toward DNA but also showed greater anticancer potency with least IC50 value as compared to ASB-2.


Assuntos
Antineoplásicos , Tiadiazóis , Antineoplásicos/farmacologia , DNA , Células HEK293 , Humanos , Ibuprofeno/farmacologia , Simulação de Acoplamento Molecular , Bases de Schiff , Tiadiazóis/farmacologia
20.
J Mol Model ; 26(10): 291, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32995926

RESUMO

Herein, we demonstrate effect of substituents on optoelectronic properties of discotic liquid crystals (DLCs) by using density functional theory (DFT) calculations at B3LYP/Lanl2Z level of theory. Three parent DLCs, namely, (1) benzene-1,3,5-triyl tris(3,5-dialkoxybenzoate), (2) N1, N3, N5-tris(3-alkoxyphenyl)benzene-1,3,5-tricarboxamide, and (3) trialkyl 4, 4', 4″-(benzenetricarbonyltris (azanediyl)) tribenzoate benzoate and their -N and -S group derivatives of 1, 2, and 3, were investigated to observe the change in optoelectronic response of these systems. The frontier molecular orbital studies and electron affinity values indicate that the studied compounds are stable against the oxygen and moisture present in air. The calculated charge transfer integrals, electron, and hole mobility values revealed that parent DLCs and their derivatives can be employed as an effective n-type material for OLEDs; however, derivatives have enhanced charge transfer values compared with their parents. For better understanding of the thermochemistry and effect of substituents, frequency calculations were carried out. P1-D4 derivative having R = -NH-CO-CH3 terminal group came out to be theoretically the most favored having the lowest ΔG value. Computed UV/visible spectroscopic analysis showed minimum absorbance and maximum transmittance for derivative P2-D1 having -S-NH2 substituent. Molecular electrostatic potential surfaces mapped at potential range, i.e., - 8.531e-3esu to + 8.531e-3esu, describe electrophilic and nucleophilic characteristics. Introduction of electron donor groups enhanced electrical conductivity, excitation energy, and charge transfer integral, thus increasing optoelectronic properties of DLCs. However, these claims require further experimental verification.

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