RESUMO
The remarkable spin-charge interconversion ability of transition metal dichalcogenides (TMDs) makes them promising candidates for spintronic applications. Nevertheless, their potential as spintronic terahertz (THz) emitters (STEs) remains constrained mainly due to their sizable resistivity and low spin Hall conductivity (SHC), which consequently result in modest THz emission. In this work, the TMD PtTe2, a type-II Dirac semimetal is effectively utilized to develop efficient STEs. This high efficiency primarily results from the large SHC of PtTe2, stemming from its low resistivity and significant spin-to-charge conversion efficiency, attributed to surface states and the local Rashba effect in addition to the inverse spin Hall effect. Remarkably, the peak THz emission from PtTe2/Co-STE exceeds that of Pt/Co-STE by â¼15% and is nearly double that of a similarly thick Pt/Co-STE. The efficient THz emission in the PtTe2/Co heterostructure opens new possibilities for utilizing the semimetal TMDs for developing THz emitters.
RESUMO
The in vitro antimicrobial properties of some chalcones (1A-1C: ) and chalcone tethred 1,4-disubstituted 1,2,3-triazoles (2A-2U: ) towards different microbial strains viz. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger and Candida albicans are reported. Compounds 2G: and 2U: exhibited better potency than the standard Fluconazole with MIC values of 0.0063 µmol/mL and 0.0068 µmol/mL, respectively. Furthermore, molecular docking was performed to investigate the binding modes of two potent compounds 2Q: and 2G: with E. coli topoisomerase II DNA gyrase B and C. albicans lanosterol 14α-demethylase, respectively. Based on these results, a statistically significant quantitative structure activity relationship (QSAR) model was successfully summarized for antibacterial activity against B. subtilis.
Assuntos
Antibacterianos/farmacologia , Chalconas/farmacologia , Triazóis/farmacologia , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/farmacologia , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/enzimologia , Chalconas/química , Sistema Enzimático do Citocromo P-450/metabolismo , DNA Girase/metabolismo , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Fluconazol/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/metabolismo , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Triazóis/químicaRESUMO
A library of N-Boc protected Leucine-linked 1,4-disubstituted 1,2,3-triazoles was synthesized and fully characterized, in high yield via copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. In vitro antibacterial activity showed that compound 4h found to be more potent than the reference drug Ciprofloxacin (MIC: 0.0196 µmol/mL) against tested bacterial strains S. entrica, B. subtilis, S. aureus, E. coli and P. auroginosa with MIC: 0.0148, 0.0074, 0.0148, 0.0074, and 0.0074 µmol/mL, respectively and antifungal activity with MIC: 0.0148 µmol/mL as compared to reference drug Fluconazole (MIC: 0.0102 µmol/mL) against A. niger and C. albicans fungal strains. Further, the molecular docking study on 4h and its predecessor alkyne 3 by choosing E. coli topoisomerase II, DNA Gyrase (PDB ID: 1KZN) showed better binding with triazole than alkyne and these results were supported by DFT study using B3LYP/6-311G(d,p) basis set.
Assuntos
Simulação por Computador , Leucina/química , Triazóis/síntese química , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/metabolismo , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Técnicas de Química Sintética , DNA Girase/química , DNA Girase/metabolismo , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/metabolismo , Humanos , Simulação de Acoplamento Molecular , Conformação Proteica , Triazóis/metabolismo , Triazóis/farmacocinéticaRESUMO
Pristine ZnO has been widely explored for its use in UV photodetectors; however, the utility of ZnO in broadband photodetectors is still a challenge as it absorbs in the UV region only with low quantum efficiency and responsivity that can be accredited to the high recombination rate of photo-generated charge carriers. To address this issue, we report an Fe-doped 2D ZnO thin film, obtained through band gap engineering, and a 1D electrospun mixed-inorganic monoclinic BiVO4 nanofiber heterostructure on an ITO-coated PET substrate-based broadband photodetector (PD) with ultra-high responsivity and EQE values in comparison to PDs fabricated using expensive cleanroom techniques. BiVO4 plays the dual role of absorbing photons in the visible and NIR regions and creating local electric fields at the interface of the Fe-doped ZnO (FZO)-BiVO4 heterostructure, which helps in the separation of electron-hole pairs. The robustness of the flexible PD was further examined under the conditions of repeated bending cycles (up to 500), yielding a stable response. The responsivity values obtained for UV, visible and NIR irradiation are 7.35 A W-1, 3.8 A W-1 and 0.18 A W-1 with very high EQE values of 2501.7%, 851.2% and 28.3%, respectively. The facile and cost-effective fabrication of the device with high performance provides a new approach for developing flexible electronics and high-performance optoelectronic devices.
RESUMO
A simple and green synthesis of some fluorinated chalcone-triazole hybrids from propargylated chalcones and organic azides catalyzed by cellulose supported copper nanoparticles click reaction is reported. All the synthesized compounds were well characterized by various analytical and spectroscopic methods. The X-rays crystallographic study of compounds 6k revealed the self assembling properties. The antimicrobial screening results of all the synthesized compounds revealed that most of the triazole hybrids exhibited significant efficacy against tested bacterial and fungal strains. The activity results showed the synergistic effect of biological activity when two pharmacophoric units, i.e. chalcone and 1,2,3-triazole are conjugated. Further, docking simulation of the most active compounds 6p into Escherichia coli topoisomerase II DNA Gyrase B was also carried out.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Chalcona/farmacologia , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Chalcona/síntese química , Chalcona/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Halogenação , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/químicaRESUMO
A series of new dehydroacetic acid chalcone-1,2,3-triazole hybrids as potential antimicrobial agents was designed, synthesized and characterized by FTIR, NMR and HRMS spectral techniques. All the synthesized compounds were screened in vitro against four bacterial strains (Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa) and two fungal strains (Aspergillus niger and Candida albicans). The antimicrobial results indicated that some of the compounds showed remarkable activities comparable to the standard drugs. Most of the compounds exhibited better efficacy compared to the DHA, which is itself an antimicrobial agent. The synergistic effect in biological activity was observed when DHA, chalcone and 1,2,3-triazole are conjugated. The molecular modeling studies of compound 5j into E. coli topoisomerase II DNA gyrase B were also performed.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Chalcona/farmacologia , Desenho de Fármacos , Pironas/farmacologia , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Chalcona/química , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Pironas/química , Staphylococcus epidermidis/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
Cancer is a class of formidable disease with high degree of mortality. Despite much progress in chemotherapy, the problem of drug resistance has led to the search for newer leads with superior efficacy. 1,2,3- Triazoles are among a vast number of nitrogen containing heterocycles studied extensively as pharmacologically important scaffolds. Recently developed copper(I)-catalyzed cycloaddition reaction between organic azides and terminal alkynes yielding 1,4-disubstituted 1,2,3-triazoles has attracted considerable attention because it allows the construction of a vast array of 1,2,3-triazoles with significant potential in pharmaceutical chemistry. In this article, an attempt to summarize the wide range of anticancer agents derived from copper(I)-catalyzed azide alkyne cycloaddition reported by the authors worldwide, has been made. This review includes articles published from 2010 onwards and summarizes the recent progress on the development of 1,4-disubstituted 1H-1,2,3-triazoles as novel anticancer chemotypes with high therapeutic indices.
Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Triazóis/farmacologia , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias/patologia , Triazóis/químicaRESUMO
A series of chalcone linked-1,2,3-triazoles was synthesized via cellulose supported copper nanoparticle catalyzed click reaction in water. The structures of all the compounds were analyzed by IR, NMR and Mass spectral techniques. All the synthesized products were subjected to 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay against a panel of four human cancer cell lines (MCF-7, MIA-Pa-Ca-2, A549, HepG2) to check their anticancer potential. Compound 6h was found to be most active against all the tested cancer cell lines with IC50 values in the range of 4-11 µM and showed better or comparable activity to the reference drug against all the tested cell lines. Cell cycle analysis revealed that compound 6h induces apoptosis and G2/S arrest in MIA-Pa-Ca-2 cells. Compound 6h triggers mitochondrial potential loss in pancreatic cancer MIA-Pa-Ca-2 cells. Further, Compound 6h also triggers caspase-3 and PARP-1 cleavage, which increases in dose dependent manner.