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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125114, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39288604

RESUMO

A number of new substances were included into the (5Z)-5-[(2-piperidinequinoline-3-yl)methyl]-2-chloroquinoline structural framework. The condensation process 2-chloroquinoline, which served as a crucial reagent in the reaction with 3-carbaldehydes to produce 2,4-thiazolidinedione, allowed for the production of 1,3-thiazolidine-2,4-dione. The newly developed substances were described by means of their reactions with halide compounds, particularly those pertaining to substituted N-alkylation. Elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), and proton nuclear magnetic resonance spectroscopy (1H NMR) were used to identify the chemical. Furthermore, the antibacterial activity of the produced compounds was evaluated in vitro against a range of pathogens, including Bacillus subtilis, and Escherichia coli. Moreover, docking experiments were conducted using the PDF enzyme of E. coli to improve our understanding of the binding mechanism between the synthesized 5(A-N) compounds and the enzyme.

2.
J Biomol Struct Dyn ; : 1-9, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254288

RESUMO

The intercalative yeast t-RNA binding behavior of some metallo-surfactant complexes, Co(ip)2(TA)2](ClO4)3 (1) and [Co(dpq)2(TA)2](ClO4)3 (2) where TA = Tetradecylamine (Myristylamine), ip = imidazo[4,5-f][1,10]phenanthroline and dpq = dipyrido[3,2-d:2'-3'-f]quinoxaline containing π-conjugated systems (both below and above critical micelle concentration) have been investigated by means of absorption spectral titration, competitive binding, circular dichroism, cyclic voltammetry, and viscometry measurements. Absorption spectral titration results implicate yeast tRNA has significant effects on the binding behaviors of two surfactant complexes via intercalative mode showed a significant absorption band of hypochromicity with red shift. The intrinsic binding constant values below and above CMC were determined as Kb = 6.12 × 105 M-1, 2.31 × 106 M-1, for complex (1) and 7.23 × 105 M-1, 3.57 × 106 M-1, for complex (2). In both sets of complexes (1) and (2), the complexes bind more strongly to yeast tRNA in the above critical micelle concentration can be hydrophobic and confirm intercalation. Competitive displacement studies confirmed that complexes bind to yeast tRNA via intercalative mode. Cyclic voltammetry studies suggest the increasing amounts of yeast tRNA, the cathodic potential Epc for the two complexes shows a positive shift in peak potential indicated the process of binding via intercalation. These observations were further validated by CD, and hydrodynamic measurements. All these studies suggesting that a surfactant complex binds to yeast tRNA appear to be mainly intercalative because of hydrophobicity due to extending aromaticity of the π system of the ligand and planarity of the complex has a significant effect on tRNA binding affinity increasing in the order of complexes containing ligands ip < dpq.Communicated by Ramaswamy H. Sarma.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122693, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37028097

RESUMO

In this study, we report a new class of metallo-surfactant assisted silver nanoparticle produced by reduction process via AgNO3 solution and extract of Turnera Subulata (TS) in aqueous which act as reducing and metallo-surfactant [Co(ip)2(C12H25NH2)2](ClO4)3 (ip = imidazo[4,5-f][1,10]phenanthroline) act as stabilizing agent. In this study the silver nanoparticles produced using Turnera Subulata extract has showed yellowish brown color formation and an absorption peak at 421 nm signaling the biosynthesis of silver nanoparticles. The presence of functional groups in the plant extracts were identified by FTIR analysis. In addition, the effects of ratio, changing the concentration of the metallo surfactant, TS plant leave extract, metal precursors, and pH of the medium have been investigated on the scale of the Ag nanoparticles. Spherical shaped, crystalline in nature and ∼50 nm sized particles were recorded using TEM and DLS analysis. Furthermore, the mechanistic insights into cysteine and dopa detection by silver nanoparticles were investigated using HR-TEM analysis. This induces aggregation in stable silver nanoparticles owing to selective and strong interaction of -SH group of cysteine with silver nanoparticle surface. The biogenic Ag NPs are found to be highly sensitive to amino acids of dopa and cysteine with the diagnosis maximum for both amino acids as low as 0.9 µM (dopa) and 1 µM (cysteine) under optimized conditions.


Assuntos
Aminoácidos , Nanopartículas Metálicas , Colorimetria , Nanopartículas Metálicas/química , Cisteína/química , Prata/química , Tensoativos , Extratos Vegetais/química , Di-Hidroxifenilalanina
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 122015, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36283203

RESUMO

The binding interaction of surfactant cobalt(III) complex, cis-[Co(bpy)2(HA)2](ClO4)3, in which bpy is 2,2-bipyridine and HA is hexadecylamine or cetylamnine with DNA was through intercalative mode via the long aliphatic chains present in the ligands. The binding was investigated by various techniques, electronic absorption, fluorescence spectroscopy, circular dichroism (CD), cyclic voltametry (CV) and viscosimetry measurements. The spectroscopic studies together with cyclic voltammetry and viscosity experiments support that the surfactant cobalt(III) complex binds to calf thymus DNA by intercalation through the aliphatic chain present in the complex into the base pairs of DNA. The presence of bipyridine ligand with larger π-frame work may also enhance intercalation. UV-vis., spectrum showed 4 nm bathochromic shift of the absorption band at 352 nm along with significant hypochromicity for the absorption band of the complex. The intrinsic binding constants(at below and above CMC are Kb = 2.41 × 105M-1, Kb = 3.12 × 106M-1 respectively) is more in keeping with intercalators and suggests this binding mode. The viscosity measurements showed that the surfactant cobalt(III) complex-DNA interaction can be hydrophobic and confirm intercalation. Moreover, the complex induced detectable changes in the CD spectrum of CT-DNA. Competitive binding study with ethidium bromide (EB) shows that the surfactant complex exhibits the ability to displace the DNA-bound EB indicating that the complex binds to DNA in strong competition with EB for the intercalative binding site. Also, CV results confirm this mode because, with increasing the CT-DNA concentration, shift to higher potential was observed. Besides the effect of binding of surfactant cobalt(III) complex to DNA in presence of ß-cyclodextrin has also studied. This binding of the surfactant cobalt(III) complex in presence of ß-cyclodextrin medium has been prevented (at below and above CMC are Kb = 5.45 × 104M-1, Kb = 6.92 × 105M-1 respectively) due to the incorporation of the aliphatic chains into the cavity of ß-cyclodextrin. In presence of ß-cyclodextrin the binding occur through surface and (or) groove binding can be attributed to the inclusion of the long aliphatic chain that is present in one of the ligands into cyclodextrin.


Assuntos
Tensoativos , beta-Ciclodextrinas , Tensoativos/química , Cobalto/química , 2,2'-Dipiridil , Ligantes , DNA/química , Tomografia Computadorizada por Raios X , Viscosidade
5.
Biomimetics (Basel) ; 7(4)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36546921

RESUMO

Electronic absorption spectroscopy was used to study the ETR of surfactant-cobalt(III) complexes containing imidazo[4,5-f][1,10]phenanthroline, dipyrido[3,2-d:2'-3'-f]quinoxaline and dipyrido[3,2-a:2',4'-c](6,7,8,9-tetrahydro)phenazine ligands by using ferrocyanide ions in unilamellar vesicles of dipalmitoylphosphotidylcholine (DPPC) and 1-butyl-3-methylimidazolium bromide ((BMIM)Br), at different temperatures under pseudo-first-order conditions using an excess of the reductant. The reactions were found to be second-order and the electron transfer is postulated as occurring in the outer sphere. The rate constant for the electron transfer reactions was found to increase with increasing concentrations of ionic liquids. Besides these, the effects of surfactant complex ions on liposome vesicles in these same reactions have also been studied on the basis of hydrophobicity. We observed that, below the phase transition temperature, there is an increasing amount of surfactant-cobalt(III) complexes expelled from the interior of the vesicle membrane through hydrophobic effects, while above the phase transition temperature, the surfactant-cobalt(III) complexes are expelled from the interior to the exterior surface of the vesicle. Kinetic data and activation parameters are interpreted in respect of an outer-sphere electron transfer mechanism. By assuming the existence of an outer-sphere mechanism, the results have been clarified based on the presence of hydrophobicity, and the size of the ligand increases from an ip to dpqc ligand and the reactants become oppositely charged. In all these media, the ΔS# values are recognized as negative in their direction in all the concentrations of complexes employed, indicative of a more ordered structure of the transition state. This is compatible with a model in which these complexes and [Fe(CN)6]4- ions bind to the DPPC in the transition state. Thus, the results have been interpreted based on the self-aggregation, hydrophobicity, charge densities of the co-ligand and the reactants with opposite charges.

6.
Anticancer Agents Med Chem ; 19(15): 1855-1862, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31429695

RESUMO

BACKGROUND: Cancer remains a major health concern throughout history and is responsible for huge numbers of deaths globally. The sensitivity of cancer cells to anticancer drugs is a crucial factor for developing effective treatments. METHODS: Pyrrolo[1,2-a]azepines coupled with benzothiazole and fluorinated aryl thiourea scaffolds have been synthesized, and their potential as cytotoxic agents was investigated against different cancer cell lines such as human ovarian cancer (SK-OV-3), cervical cancer (HeLa), colon adenocarcinoma (HT-29) and non-small-cell lung carcinoma (A549). Cytotoxicity of new compounds was confirmed using SRB assay against non-cancer MDCK cell line. In addition, free radical scavenging activity of new pyrrolo[1,2-a]azepines was examined by adopting DPPH and ABTS assays. RESULTS: The results concluded that the presence and position of fluorine atom(s) on the thiourea unit played a significant role in order to gain anticipated efficacies. Results of the cytotoxic assay against non-cancer MDCK cells showed that these new derivatives are safe to study further. New structures were confirmed using spectral and elemental analyses. CONCLUSION: Pyrrolo[1,2-a]azepines endowed with a benzothiazole entity and fluorinated aryl thiourea substituents were derived aiming to furnish remarkable antioxidant and anticancer activities. New molecules generated showed interesting biological result correlated with the structure and substituent of the final derivatives. Specifically, numbers and position of fluorine atoms on the thiourea unit influenced the biological profile of the mentioned compounds.


Assuntos
Antineoplásicos/química , Antioxidantes/química , Azepinas/química , Benzotiazóis/química , Tioureia/química , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Azepinas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Halogenação , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
7.
Arch Pharm (Weinheim) ; 352(9): e1900051, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31339585

RESUMO

Chrysin-based sulfonylpiperazines 7a-k were synthesized and investigated for their in vitro free radical scavenging potential as well as cytotoxic efficacies against selected cancer cell lines. Cytotoxicity of the new compounds toward noncancer cells was confirmed using the SRB assay against Madin-Darby Canine Kidney cells. Reaction of piperazine with different substituted benzenesulfonyl chlorides in triethylamine furnished sulfonylpiperazines (3a-k), which were then allowed to react with 7-(4-bromobutoxy)-5-hydroxy-2-phenyl-4H-chromen-4-one (6) prepared reacting chrysin with 1,4-dibromobutane to give the final derivatives 7a-k. The results concluded that chrysin-sulfonylpiperazines exerted better antioxidant and anticancer efficacies than previously studied chrysin-piperazine precursors. For example, compounds 7h, 7j, and 7k with 4-OCF3 , 4-OCH3 , and 2,4-diOCH3 groups exhibited the best antioxidant potential against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals. Moreover, halogenated analogues (7b, 7c, 7g, and 7h) demonstrated promising anticancer potential against SK-OV3, HeLa, and HT-29 cell lines, whereas those bearing a methoxy functional group (7j and 7k) had beneficial effects against the cell lines A-549 and HT-29. Thus, it can be confirmed from the bioassay results that the overall structural design as well as proper substitution is crucial to deliver the anticipated biological effects. Spectroscopic techniques such as FT-IR, 1 H NMR, 13 C NMR, mass and elemental analysis (CHN) were carried out to confirm the final structures.


Assuntos
Antineoplásicos/síntese química , Antioxidantes/síntese química , Flavonoides/química , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Sobrevivência Celular/efeitos dos fármacos , Cães , Radicais Livres/química , Células HT29 , Células HeLa , Humanos , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Estrutura Molecular , Picratos/química , Ácidos Sulfônicos/química
8.
Bioorg Chem ; 87: 23-30, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30852234

RESUMO

Two series of sulfonylpiperazines linked [1,3]dioxolo[4,5-g]chromenones were synthesized featuring phenyl (7a-k) and chalcone (12a-k) bridge representing flavones or homoisoflavonoids core. New molecules are synthesized utilizing aldol condensation to inspect as antioxidants against DPPH and ABTS+ and antiproliferative agents toward selected human cancer cell lines. Cytotoxicity of new compounds was confirmed using SRB assay against non-cancer MDCK cell line. The results concluded that both individual structures of 7 and 12 were vital for modulating pharmacological potencies and presence of different electron withdrawing and electron donating functional group(s) on the phenylsulfonyl entity yielded varied biological effects. Substituent h (OCF3) and j, k (OCH3) were found to play a crucial role scavenging DPPH and ABTS+ as well as inhibiting cancer cell lines SK-OV-3 and HT-29. Moreover, molecules bearing halogen atom(s) such as substituent b-g expressed excellent inhibitory potential against HeLa and A-549 cancerous cell lines. Bioassay data displayed some interesting structure-activity relationships which are discussed in this paper. The results justified that tested derivatives are promising antioxidants and cytotoxic agents and warrant further structural optimization and bioassay studies. Spectroscopic techniques such as FT-IR, 1H NMR, 13C NMR and elemental analysis (CHN) were carried out to confirm the final structures.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cromonas/farmacologia , Piperazina/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antioxidantes/síntese química , Antioxidantes/química , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromonas/química , Cães , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Picratos/antagonistas & inibidores , Piperazina/química , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidores
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