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•Investigation of the corrosion inhibition of two pyrazole derivatives.•The adsorption of inhibitors obeys Langmuir adsorption isotherm and surface morphology was examined by ...SEM.•Potentiodynamic polarization curves reveal that tested inhibitors acts as a mixed type.•DFT, MC and MD simulations were performed.
Corrosion inhibition is a vast area of research and its development is attracting increasing attention from researchers. Given the different biological activities that present these compounds, in the present work, we investigated two dimethyl-1H-pyrazole derivatives namely: (E)-N'-benzylidene-2-(3,5-dimethyl-1H-pyrazol-1-yl)acetohydrazide (DPP) and E)-N'-(4-chlorobenzylidene)-2-(3,5-dimethyl-1H-pyrazol-1-yl)acetohydrazide (4-CP) as corrosion inhibitors for mild steel (MS) in 1 M HCl using weight loss (WL), electrochemical techniques potentiodynamic (PP) polarization, electrochemical impedance spectroscopy (EIS), surface examinations by scanning electron microscopy (SEM). Theoretical studies such as quantum chemical and molecular simulations studies were used to support the experimental findings. Analyses on mass loss (ML) and electrochemical properties confirmed adsorption of inhibitor as a protective layer on the surface of MS. The inhibition efficiency of DPP and 4-CP was enhanced as the concentration of inhibitors increased but decrease with rising temperature. The maximum inhibition efficiency for DPP and 4-CP at 10−3 M concentration has been obtained 80 % and 94 % respectively. Analysis of adsorption isotherms revealed that adsorption of DPP and 4-CP on MS surface follows Langmuir isotherm. Potentiodynamic polarization study confirmed that DPP and 4-CP are of mixed-kind inhibitors. EIS investigations displayed that the polarization resistance raised to 93.7 Ω cm2 and 287.7 for DPP and 4-CP, respectively at 10-3 M. Furthermore, to get detailed electronic/atomic-level findings regarding the dimethyl-1H-pyrazole derivatives interactions over the MS substrate, theoretical investigations applying molecular dynamics (MD) and density functional theory (DFT) methods were conducted. The results extracted from these approaches affirmed the DPP and 4-CP adsorption on the MS adsorbent.
This work aims to evaluate the antimicrobial activity of some new quinoline derivatives linked to pyrazole derivatives. The target compounds pyrazolylvinylquinoline 11a-g and 12a-g were achieved by ...the reaction of 2-chloro-6-nitro-3-quinolinecarboxaldehyde (4) with bromotriphenylphosphonylmethylpyrazole derivatives 9a,b to give the new quinoline derivatives 10a,b which in turn reacted with different aryl amines to afford 11a-g and 12a-g. Pyrazole derivatives 9a,b were obtained by the reaction of hydroxymethylpyrazole derivatives 8a,b with triphenylphosphine hydrobromide. Antimicrobial evaluation of the newly synthesized compounds showed that most of the new compounds appeared active toward Gram-positive bacteria more than Gram-negative bacteria. The biological evaluation of compounds 12d-g displayed the highest antimicrobial activity against the tested microorganism strains. Additionally, compounds 12d and 12f showed excellent activity against P. aeruginosa (MIC50 0.019 mg/mL), while compounds 11d, 11f, 12e, and 12g displayed good activity against the same microorganism (MIC50 0.07 mg/mL). On the other hand, most of the new compounds have moderate activity against E. coli. Compounds 12d and 12f showed excellent activity versus C. albicans in vitro antifungal activity (MIC50 0.15 mg/mL) comparing to or slightly lower than that of Fluconazole. Using molecular docking simulations, we evaluated the binding affinities and interactions of four chosen derivatives 12d-g with a target PDB code 3WT0 protein.
One important class of heterocyclic compounds, are pyrazole derivatives. These compounds consist of a pyrazole core and have many biological and pharmacological activities. Also, some of natural ...products having pyrazole molecules in their structures that give particular properties to these compounds. Today, interesting to nanoparticles due to the special characteristics of them for the organic synthesis, is increased. In this review, we focused on the synthesis different derivatives of pyrazole using nanoparticles.
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In this study, six pyrazole derivatives containing hetero atoms have been analyzed using theoretical calculation method. The ligands were tested by HF, B3LYP and M06-2X methods using 3-21G, 6-31G, ...6-31G(d, p), and sdd basis sets. The results showed that Ligand 5 has a HOMO value of -7.470 at HF / 6-31g (d.p) level. These ligands were investigated in IR, NMR, and UV-VIS spectrum, then experimental values were compared with IR and NMR spectrum data. The solvents, whose effects were investigated in UV-VIS spectrum, were gas phase (ε = 1), toluene (ε = 2.3741), chloroform (ε = 4.7113), methanol (ε = 32.613), water (ε = 78.3553), and n-methylformamide-mixture (ε = 181.56). Metal complexes of tested ligands were produced with copper, nickel, and zinc. Lastly, the interactions between these six pyrazole derivatives and three proteins, namely 3dju, 2IJN, and 1JNX, were also examined. Biological and anti-cancer properties of six pyrazole derivatives were analyzed by DockingServer. In docking calculations, Estimated Free Energy of Binding value of Ligand 5 was found to be -4.87, -4.82, -1.73 respectively, which indicated the highest biological activity.
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•These ligands are calculated at HF, B3LYP and M06-2X method with 3-21G, 6-31G, 6-31G(d,p) and sdd basis set.•Studied ligands are investigated IR, NMR and UV-VIS spectrum.•Biological and anti-cancer properties of six pyrazoly derivatives are analyzed by DockingServer.
Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. The presence of this nucleus in ...pharmacological agents of diverse therapeutic categories such as celecoxib, a potent anti-inflammatory, the antipsychotic CDPPB, the anti-obesity drug rimonabant, difenamizole, an analgesic, betazole, a H2-receptor agonist and the antidepressant agent fezolamide have proved the pharmacological potential of the pyrazole moiety. Owing to this diversity in the biological field, this nucleus has attracted the attention of many researchers to study its skeleton chemically and biologically. This review highlights the different synthesis methods and the pharmacological properties of pyrazole derivatives. Studies on the synthesis and biological activity of pyrazole derivatives developed by many scientists around the globe are reported.
In recent times, there has been an increased demand in the search for probing materials for numerous substances in the environment such as the detection of metals ions. In this study, a new class of ...pyrazolyl-sulfonamide derivatives of para-nitroaniline were synthesized following a multistep approach. The ligands and complexes were characterized using NMR spectroscopy, IR spectroscopy, and mass spectrometry. All the compounds C1–C3 were synthesized in very good yields (85%–92%) and their photo-physical properties measured. All the compounds show fluorescence behaviour with emissions within the UV and far visible range with quantum yields between 7.7% and 25.7%. TD-DFT calculations predictions for the electronic transitions present are in good agreement with experimental observations.
Fluorescent probing studies conducted on the compounds show that C1–C3 were analytically sensitive and possessed significant selectivity towards Cu2+ (for C3) and Zn2+ (for C1 and C2) ions with detection limits between 0.011 and 0.103 mg/L for Cu2+ ions and 0.002–0.135 mg/L for Zn2+ ions. Overall, C1 was found to be the most sensitive molecule for the metals studied, having good quantum yield and better selectivity for Zn2+ ion compared to Cu2+.
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One-third of the world's population infected tuberculosis (TB), and more than 1 million deaths annually. The co-infection between the mainly pathogen Mycobacterium tuberculosis (MTB) and HIV, and the ...incidence of drug-resistant TB, multi-drug resistant TB, extensively drug-resistant TB as well as totally drug-resistant TB have further aggravated the mortality and spread of this disease. Thus, there is an urgent need to develop novel anti-TB agents against both drug-susceptible and drug-resistant TB. The wide spectrum of biological activities and successful utilization of pyrazole-containing drugs in clinic have inspired more and more attention towards this kind of heterocycles. Numerous of pyrazole-containing derivatives have been synthesized for searching new anti-TB agents, and some of them showed promising potency and may have novel mechanism of action. This review aims to outline the recent achievements in pyrazole-containing derivatives as anti-TB agents and their structure-activity relationship.
This review aims to outline the recent advances in the discovery of pyrazole-containing derivatives as anti-TB agents and the SAR of these heterocycles. Display omitted
•This review aims to outlines the recent advances of pyrazole-containing derivatives as anti-TB agents as well as the SAR.
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Pyrazole is a five-membered aromatic heterocyclic ring with two adjacent nitrogen atoms C3H3N2H.The presence of this nucleus in pharmacological agents of various therapeutic ...categories gifts a broad spectrum of biological activities and pharmaceuticals that contain pyrazole like celecoxib (anti-inflammatory), CDPPB (antipsychotic), Rimonabant (anti-obesity), Difenamizole, (Analgesic), Betazole (H2 receptor agonist), Fezolamide (Antidepressant), etc…
The pharmacological potential of the pyrazole fraction is proved in many publication where they synthesized and evaluated pyrazoles against several biological agents. The aim of this article review is to survey recent works linking pyrazole structures to anticancer activities corresponding to 9 different type of cancer.
•Inhibition behavior of PPA and PMB for carbon steel is studied.•Both inhibitors are mixed type.•SEM, EDX and UV–Visible studies support the formation of inhibitor film on carbon steel surface.•DFT ...and MDS was performed to explain the corrosion inhibition performance of both inhibitors.
Corrosion inhibition performance of two pyrazole derivatives, namely N-((1H-pyrazol-1-yl)methyl)pyrimidin-2-amine (PPA), 2-(((1H-pyrazol-1-yl)methyl)amino)benzoic acid (PMB), carbon steel (CS) was assessed in 1 M HCl medium by means of electrochemical impedance spectroscopy (EIS), weight loss, potentiodynamic polarization measurements (PDP), Uv–visible spectroscopy, and scanning electron microscopy with energy dispersive X-ray (SEM- EDX), as well as molecular modeling techniques. Results indicated that the inhibition efficiencies increased with the concentration of inhibitor, but decreased proportionally with temperature to reach a maximum of 94 % for PPA and 92 % for PMB at 10−3 M and 303 K, respectively, whereas it was 76.9 and 72.3 %, respectively, at 10−3M and 333 K. PDP plots reveal the anodic-type behavior of PPA while the mixed-type behavior of PMB. The EIS plots showed that charge transfer resistance increased and double-layer capacitance decreased with increasing the concentration of studied inhibitors due to the adsorption of inhibitor molecules on the CS surface. Moreover, the adsorption of pyrazole derivatives on the CS surface obeys the Langmuir adsorption isotherm and contains a chemisorption mechanism. Thermodynamic parameter magnitudes suggest that pyrazole derivatives were physiosorbed on the CS surface. SEM-EDX revealed the formation of an adsorption-related protective inhibitor film on the CS surface. Theoretical studies using density functional theory (DFT) for PPA and PMB molecules are performed in gas and aqueous phase conditions. The calculated data are in good agreement with the experimental results. Molecular Dynamic simulations (MDS) exhibit that the neutral and protonated forms of PPA and PMB adsorb on Fe (110) surface with a parallel mode.
The reaction of hydroxymethyl pyrazole derivatives with one equivalent of the appropriate primary amine yields N-((1h-pyrazol-1-yl) methyl) pyrimidin-2-amine (L1), 2-(((1h-pyrazol-1-yl) methyl) ...amino) benzoic acid (L2), and ethyl 5-methyl-1-(((6-methyl-3-nitropyridin-2-yl) amino) methyl)-1h-pyrazole-3-carboxylate (L3). The structure of synthesized compounds (L1-L3) was identified by FT-IR, UV–visible, proton NMR spectroscopy, mass spectroscopy, and single crystal X-ray crystallography. The armed pyrazoles (L1-L3) were crystallized in the space groups C2/c, P21/n and P-1 for L1, L2, and L3 respectively. Crystallographic analysis revealed that N–H of the amine group and Nitrogen or Oxygen atoms are in-plane with the aromatic ring. The aminomethyl chain forms a distorted second plane. The angle between the two planes is observed to be 76.07° (N2–C7–N5–N19) for L1, 62.12° (N34–C63–N22–N35) for L2, 60.84° (N3–C8–N2–N1), and 0.41° (N1–C4–C3–O1/O2) for L3 was studied. Theoretical physical and chemical properties calculations have been performed on the studied armed pyrazoles (L1-L3) using three different programs: Petra, Osiris, & Molinspiration (POM). The geometric parameters of the optimized structure are in agreement with the experimental data obtained from the X-ray structures. The origin of the biological activity against breast cancer and microbes has also been confirmed.
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•The antitumor, antimicrobial activity of novel armed pyrazole derivatives was evaluated.•Identification of potential combined antimicrobial/antitumor pharmacophore sites by crystallographic analyses.•Computed quantum chemical descriptors based upon POM calculations have been used to correlate with biological activity.
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