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The benzimidazole moiety in the title molecule, C19H25N5O, is almost planar and oriented nearly perpendicular to the triazole ring. In the crystal, C—H...O hydrogen bonds link the molecules into a network structure. There are noμ-μinteractions present but two weak C—H...π(ring) interactions are observed. A Hirshfield surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (62.0%), H...C/ C...H (16.1%), H...N/N...H (13.7%) and H...O/O...H (7.5%) interactions. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated via the dispersion energy contributions in the title compound. [ABSTRACT FROM AUTHOR]

This work reports on an inhibition and adsorption performance study of two quinazoline derivatives ((2-(2-chlorophenyl)-2,3-dihydroquinazolin-4(1H)-one) and (2-(2,4- dichlorophenyl)-2,3-dihydroquinazolin-4(1H)-one)) named ZB3 and ZB4, which were synthesized and examined using carbon nuclear magnetic resonance (13C NMR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The assessment of the corrosion prevention of these two compounds for MS in 1.0 M HCl was performed employing potentiodynamic polarization (PDP) and (EIS) electronic impedance spectroscopy. The experiments performed showed that both derivatives operate well to prevent corrosion and their efficiencies exceed 85% at a concentration of 10-3. Moreover, it is discovered that the three chemicals' adsorption on the m-steel surface complies with Langmuir adsorption isotherm equation. The m-steel surface submerged in the corrosive solution was characterized by scanning electron spectroscopy (SEM) in conjunction with energy dispersive spectroscopy (EDS), spectroscopy using atomic force microscopy (AFM), X-Ray diffraction, and FTIR analysis. The findings showed that the examined inhibitors are well adsorbed, generating a barrier layer for the msteel's surface. DFT calculations and Monte Carlo (MC) simulation were used to directly correlate the electronic and adsorption properties, respectively, with the experimental corrosion inhibition efficiencies obtained for quinazoline and its 2 investigated derivatives. [ABSTRACT FROM AUTHOR]

In the present study, a simplest and most effective method was applied to removal of Cu2+ ions from an aqueous solution using Montmorillonite clay, nontoxic and abundantly available as an adsorbent. The used adsorbent was characterized using X-ray diffraction (XRD), the X-ray fluorescence spectrometry, Fourier Transform Infrared Spectroscopy (FT-IR) and scanning electron microscope (SEM) coupled with EDX analysis. Adsorption experiments were conducted under various conditions, i.e., contact time, initial concentration, pH of Cu(II) ions solution, adsorbent mass, and particle size. The results proved that the adsorption of Cu(II) ions by Montmorillonite clay was favorable at pH=5.5 with an extraction yield of 85% after 30 min contact. The equilibrium isotherm data were analyzed using the Langmuir and Freundlich equations. In all cases, the adsorption process fitted the second-order kinetics well, and the isotherm equation due to Freundlich showed good fits with the experimental data. In order to value our Cu-Montmorillonite clay (Cu-MC) support, we thought of applying it as recyclable heterogeneous catalyst for the condensation of Knoevenagel. The model reaction was carried out at room temperature, using a quantity of 0.5 mg of catalyst and a volume of 2ml of ethanol, the reaction yield was excellent (87%). The recyclable solid catalyst was effective for five successive cycles, indicating that this clay is a potentially eco-friendly heterogeneous catalyst. [ABSTRACT FROM AUTHOR]

The 4H-pyranopyrazoles are an important class of heterocyclic compounds due to their pharmacological and biological properties.[1] Compounds bearing the pyranopyrazole system have been found to have various biological activities, for instance antimicrobial,[2] anti-cancer[3] and anti-inflammatory properties,[4] analgesic activity,[5] activity as hypoglycemic,[3] hypotensive,[6] and vasodilatory agents,[7] inhibitory activity toward human Chk1 kinase,[8] molluscicidal activity[9] and antifungal properties.[10] In addition, such heterocycles bearing 4H-pyran units are important precursors in the synthesis of a large family of medicinally useful compounds.[11] The use of natural catalysts in organic synthesis offers many advantages in sustainable chemistry because the catalysts are inexpensive, readily available, non-toxic and show high selectivity. In summary, a catalyst derived from snail shells proved to be extremely effective in the four-component synthesis of pyranopyrazole derivatives I via i the one-pot reaction of aromatic aldehydes, ethyl acetoacetate, hydrazine, and malononitrile. Maleki, H. Eshghi, M. Barghamadi, N. Nasiri, A. Khojastehnezhad, S. S. Ashrafi and O. Pourshiani, Res. Chem. Intermed., 42, 3071 (2016). [Extracted from the article]

In present work, two heterocyclic compounds namely 7-amino-2-(p-tolyl)-2H-thiazolo[3,2-a]pyrimidine-3,5-dione (ATTP) and 7-amino-2-(4-chlorophenyl)-2H-thiazolo [3,2-a]pyrimidine-3,5-dione (ACTP) were investigated for their inhibitory efficiencies against the corrosion of mild steel in HCl 1.0 M medium. Furthermore, the adsorption isotherm of these inhibitors was also studied, the results showing that the adsorption of inhibitors ATTP and ACTP on the surface of mild steel obey Langmuir isotherm. The negative values of ΔGads ° indicate the spontaneity of the adsorption process for both inhibitors. The calculated value of ΔGads ° indicates that the adsorption of ATTP on the surface of mild steel is mixed interaction (chemisorption and physisorption), while the calculated value of ΔGads ° of ACTP suggest the chemisorption adsorption. As well the Density Functional Theory (DFT) was used to study the relationship between the structure of the studied thiazolopyrimidines and their inhibitory efficiencies. The theoretical parameters obtained from DFT are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The inhibiting power of two compounds of thiazolopyrimidine namely 7-amino-2-(p-tolyl)-2H-thiazolo[3,2-a] pyrimidine-3,5-dione (ATTP) and 7-amino-2-(4-chlorophenyl)-2H-thiazolo[3,2-a]pyrimidine-3,5-dione (ACTP) has been studied using electrochemical methods (potentiodynamic polarization and electrochemical impedance (EIS). It is observed that the inhibition efficiency increases with the increasing of the concentration for both studied inhibitors. Also, the maximum efficiency was obtained at 10-3M concentration. Potentiodynamic study indicates that ATTP acted as a mixed type with predominant cathodic, while ACTP acted as a cathodic inhibitor. The effect of the temperature was also studied in the temperature range 298 to 338 K. The results show that the inhibitory efficiency E (%) of ATTP and ACTP increases with the increasing of the temperature from 298 K to 318 K, then it decreases for a temperature higher than 318 K. [ABSTRACT FROM AUTHOR]

An easy synthetic protocol for the synthesis of biologically active benzimidazole, benzothiazole and benzoxazole derivatives has been demonstrated using a hybrid crystal NH3(CH2)4NH3SiF6as a mild and efficient heterogeneous catalyst. Short reaction times, solvent-free conditions, good to excellent yields, easy reusability and use of an eco-friendly catalyst are some of the significant attributes of the present method. [ABSTRACT FROM AUTHOR]

We have described the catalytic activities of dicalcium phosphate dihydrate (DCPD) in the condensation reaction of various substituted benzaldehydes with active methylene compound malononitrile. The influences of reaction conditions on the corresponding catalytic behavior have been investigated. The results showed that the DCPD exhibited high catalytic activity and versatility and that it can be recycled without significant loss of its activity for the condensation reactions, which shows the material is a promising new type of heterogeneous catalyst for the condensation reactions. Meanwhile, the catalytic results of DCPD compared favorably with those of other materials for Knoevenagel reactions reported previously. [ABSTRACT FROM PUBLISHER]

Condensation reactions of various substituted benzaldehydes with active methylene compounds using DCPD as highly active heterogeneous catalyst under green reaction conditions are investigated. [ABSTRACT FROM AUTHOR]

• PY-CH 3 and PY-H act as effective inhibitors for mild steel acidic corrosion. • The adsorption of PY-CH 3 and PY-H followed the Langmuir isotherm model. • Adsorption on the surface is analyzed by AFM, SEM/EDAX, XRD, and FTIR techniques. • Theoretical data provide in-depth understanding of the experimental results. The present paper examines the adsorption of two novel heterocyclic compounds of the pyran derivatives, namely 2-amino-5-oxo-4-(p-tolyl)-4H,5H-pyrano [3,2-c]chromene-3-carbonitrile (PY-CH 3) et 2-amino-5-oxo-4-phenyl-4H,5H-pyrano [3,2-c]chromene-3-carbonitrile (PY-H)against corrosion of mild steel in molar HCl medium. The experimental investigation was carried out using several techniques including Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP). The inhibition efficiencies of PY-CH 3 and PY-H followed the order: 80.0% (PY-CH 3) < 90.0% (PY-H). The adsorption process of PY-CH 3 and PY-H on the mild steel surface follows Langmuir adsorption model. Surface characterization analysis using Scanning Electron Microscopy (SEM) coupled with Energy dispersive X-ray analysis (EDS), Atomic Force Microscopy (AFM), X-ray diffraction analysis (XRD), and Infrared Spectroscopy (FT-IR) supported the formation of a barrier layer that covers the mild steel surface. WL measurements were also tested using inductively coupled spectroscopy (ICP) and UV-Vis spectrometry (UV-Vis). The interaction mechanism of PYCH 3 and PY-H with mild steel surface and their mode of adsorption were studied using DFT and Monte Carlo (MC) simulations, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Al-air batteries are distinguished by their high theoretical energy density, yet their broader application is hindered by hydrogen evolution corrosion. This research focuses Beta (+) d-glucose (S1) and Adonite (S2) as potential corrosion inhibitors for the Al-5052 alloy within a 4 M NaOH solution. Utilizing electrochemical techniques, hydrogen evolution assessments, and surface analyses, our findings indicate enhancements in anode utilization by 21.9% for S1 and 21.1% for S2. Inhibition efficiency reached 65.5% for S1 and 65.1% for both additives at a concentration of 10-3 M. Additionally, the introduction of S1 and S2 markedly increased the nominal specific capacity (654 mA h g -1 for S1 and 629 mA h g -1 for S2) and energy density (1922 W h kg -1 for S1 and 1849 W h kg -1 for S2) of the batteries. These results suggest that managing the electrolyte composition with these additives can significantly enhance battery performance in alkaline environments. Supporting our experimental findings, density functional theory (DFT) and molecular dynamics (MD) analyses confirmed improved anode passivation and beneficial molecular interactions, contributing to the reduction of corrosion in the Al-5052 alloy.