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Background: Benzimidazoles have a wide range of synthetic applications in medicinal chemistry and biological activities like anti-tumor/anti-proliferative activities etc. Moreover, different heterocyclic moieties attached to the benzimidazole ring improved anticancer activities. Methods: All the chemicals were purchased from Aldrich Chemical Company, are of AR grade and used as received. Microanalytical data (C, H, and N) were analyzed on a Carlo Erba model 1108 analyzer. Melting points were measured by the Kofler apparatus and were uncorrected. Spectroscopic data were obtained using the following instruments: Fourier transform infrared spectra (KBr discs, 4000-400 cm-1) by Shimadzu IR-408 Perkin Elmer 1800 instrument; 1H NMR and 13C NMR spectra by JEOL Resonance Inc. Tokyo, Japan, JNM-ECZ400S/L1 using DMSO-d6 as a solvent containing TMS as the internal standard. Chemical shifts (δ) are reported in parts per million (ppm), and coupling constants (J) are reported in Hertz (Hz). Results: We chose sulfosalicylic acid as a promoter for forming benzimidazole-acrylonitrile derivatives, which is an eco-friendly reaction, and we applied a series of synthesized compounds 3a-g in nematicidal activity. The results indicate that the concentrations of all treatments significantly kill M. incognita. Conclusion: This model reaction procedure provides a better method for preparing benzimidazoleacrylonitrile, which is superior to other methods. This protocol simplifies handling model reactions with mild reaction conditions, a short time period, a simple set-up, a fast reaction rate, and so on.

In present study, an isoxazole derivative, namely, (Z)-4-(4-hydroxy-3-methoxybenzylidene)-3-methylisoxazol-5(4H)-one referred here as (IOD) has been studied as an environment-friendly corrosion inhibitor for mild steel (MS) in acidic medium (1 M HCl). The present work was investigated by gravimetric, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), fourier-transform infrared (FT-IR) spectroscopy techniques. Atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) confirmed the surface morphologies of the MS surface with and without IOD in the acid medium. The inhibition efficiency (I.E.) of IOD was increased by rising its concentration attaining maximum value (96.6%) at 300 ppm at 30 °C and decreases with increasing temperature from 30 °C to 60 °C. The adsorption of studied inhibitor followed Langmuir adsorption isotherm model. The PDP study revealed that the IOD acts as a mixed-type inhibitor with predominating anodic effect. The EIS study confirmed that increasing IOD concentration enhances the charge transfer resistance (Rct) and then reduces the double layer capacitance (Cdl) owing to the development of a protective layer on the MS surface.

The present study aims to explore the effect of 2-nitroacridone, an antimicrobial compound, on low carbon steel (LCS) corrosion in acid solution (1 M HCl). The compound was tested at various concentrations (0.001−10 mM) and five temperatures (25, 35, 45, 55, and 65 °C) to determine the optimal concentration and temperature range for the best corrosion inhibiting effect. In evaluating the inhibition efficiency, weight loss measurement, potentiodynamic polarization measurement, electrochemical impedance spectroscopy, SEM/EDAX/AFM and DFT measurements were used. The inhibition efficiency increases with the increase in concentration and decreases with temperature. The maximum inhibition efficiency was found (94.96%) at 25 °C in the presence of 5 mM concentration of the studied compound. The various adsorption isotherms were also explored to find the best fit, which was found to obey the Langmuir adsorption isotherm. The thermodynamic parameters (Ea, Kads, ΔG°ads) have also been calculated and discussed. The potentiodynamic polarization study revealed that 2-nitroacridone behaved as a mix-type of inhibitor that predominantly inhibited the anodic reaction. Moreover, a correlation between the inhibition efficiency of the studied compound and certain molecular parameters were determined by quantum chemical computations.

Phytochemical investigations of the ethanolic extract of leaves of Crateva religiosa (Family: Capparaceae) resulted in the isolation of four compounds viz. (E)-ethyl-4-((3-(4-hydroxyphenyl)acryloyl)oxy)-2-methyl-5-oxotetrahydrofuran-2-carboxylate (Cg-1) named as Cratin, Cg-2, Cg-3, and Cg-4. Cg-1 has been reported for the first time from any natural source and has not been synthesized so far. Cg-2, Cg-3, and Cg-4 were also isolated first time from this plant source. Their structures were elucidated based on chemical and physical data viz. (elemental analysis, FT-IR, UV, 1H NMR, 13C NMR, and mass). Single crystal X-ray analysis was further used for the authentication of the structure of the isolated compounds in the case of Cg-1, including chemical modification of Kaempferol Cg-2 to Cg-2-Me, to get suitable crystals for X-ray diffraction study. The isolated novel compound Cg-1 and the methyl ether of kaempferol (Cg-2-Me) were screened for DNA binding studies with ct-DNA using UV-Visible spectroscopy, fluorescence, circular dichroism studies. Molecular docking was performed to understand the interaction between DNA and the compound studied and showed groove binding interaction (non-intercalation).

Aim: The study aimed to synthesize chromeno-pyrazolo[1,2-b]phthalazine-6,9,14(7H)-trione analogs with the help of silica-supported bismuth nitrate catalyst. Background: Nitrogen-containing heterocyclic compounds are widespread, and their applications to pharmaceuticals, agrochemicals, and functional materials are becoming more and more important. Pyrazoles are an important class of compounds for new drug development, as they are the core structure of numerous biologically active compounds, including blockbuster drugs such as celecoxib, viagra, pyrazofurine, and many others. Similarly, heterocycles containing a phthalazine moiety are of current interest due to their pharmacological and biological activities; for example, pyrazolo[1,2-b]phthalazinedione is described as an anti-inflammatory, analgesic, antihypoxic, and antipyretic agent. Objective: In continuation of our ongoing investigation for the synthesis of efficient and simple approaches for the preparation of heterogeneous catalysts, herein we wish to disclose a highly efficient, simple, and one-pot synthesis of chromeno-pyrazolo-phthalazine derivatives via a one-pot multi-component reaction between 4- hydroxycoumarin, aromatic/heterocyclic aldehydes and 2,3-dihydro-1,4-phthalazinedione using silica-supported bismuth nitrate as an inexpensive, environmentally friendly and reusable catalyst under solvent-free conditions. Material and Methods: Microanalytical data (C, H, and N) were collected on Carlo Erba analyzer model 1108. The microwave synthesis was performed in Anton Paar, Monowave 300 microwave synthesizer. Melting points were measured in open glass capillaries in the Kofler apparatus and are uncorrected. Spectroscopic data were obtained using the following instruments: Fourier transform infrared spectra (KBr discs, 4000-400 cm-1) by Shimadzu IR-408 Perkin-Elmer 1800 instrument; 1H NMR and 13C NMR spectra by Bruker Avance-II 400 MHz using DMSO-d6 as a solvent containing TMS as the internal standard. Mass spectra were set down on a JEOL D-300 mass spectrometer. Results: In continuation of our ongoing studies to synthesize heterocyclic and pharmaceutical compounds by mild, facile, and efficient protocols, herein we wish to report our experimental results of the synthesis of chromeno- pyrazolo-phthalazine derivatives under solvent-free condition derivatives, using various aromatic/heterocyclic aldehydes in the presence of silica-supported bismuth nitrate catalyst. The prepared catalyst was characterized by various physical and chemical techniques. Conclusion: We have demonstrated an efficient reaction path for the synthesis of new aryl and heteroaryl chromeno-pyrazolo[1,2-b]phthalazine-6,9,14(7H)-trione by one-pot three-component condensation of aryl/ heteroaryl aldehydes, 2,3-dihydro-1,4-phthalazinedione and 4-hydroxy coumarin using silica-supported bismuth nitrate (SSBN) under microwave irradiation. The scheme not only offers the use of microwave at low temperatures and significant yield of products but also affords mild reaction conditions, without harmful solvent, shorter reaction times, high purity, operational simplicity, and easy workup.

A green approach has been developed for the synthesis of a series of benzylidene acrylate 3(a-p) from differently substituted aromatic/heterocyclic aldehydes and ethyl cyanoacetate in excellent yields (90-98%), and employing silica bonded N-(Propylcarbamoyl)sulfamic acid as a recyclable catalyst under solvent-free condition. The molecular structure of compounds 3b, 3d and 3i were well supported by single-crystal X-ray crystallographic analysis. The present protocol bears wide substrate tolerance and is believed to be more practical, efficient, eco-friendly, and compatible as compared to existing methods. In-silico approaches were implemented to find the biochemical and physiological effects, toxicity, and biological profiles of the synthesized compounds to determine the expected biological nature and confirm a drug-like compound. A molecular docking study of the expected biologically active compound was performed to know the hypothetically binding mode with the receptor. Also, reverse docking is applied to recognize receptors from unknown protein targets for drug-like compounds to explain poly-pharmacology and binding postures with different receptors.

Corrosion is the degradation of a metal due to its reaction with the environment. One of the most efficient ways of securing metal surfaces from corrosion is the use of corrosion inhibitors. Their efficacy is connected to their chemical composition, their molecular structures, and their adsorption affinities on the metal surface. This review article focuses on the prospects of different types of monomeric and gemini surfactants, mixed surfactants systems, surfactants- additives mixed systems, inhibitors-surfactants (as additives) mixed systems, and ionic liquid based surfactants as promising corrosion-inhibiting formulations in the aqueous phase and the role of surfactants in developing protective coatings. The analysis starts with an accurate overview of the characteristics, types, and structure-property-performance relationship of anti-corrosion formulations of such inhibitors.

Aim and Objective:In the synthesis of heterocyclic compounds, acrylonitrile derivatives are the most important and appropriate precursors. These compounds are the most important intermediates and subunits for the enhancement of molecules having pharmaceutical or biological interests. Nitrogen-containing compounds have received extensive consideration in the literature over the years.Materials and Methods:A facile, economic and efficient method has been developed for the synthesis of acrylonitrile derivatives using p-nitrophenylacetonitrile and aromatic/heterocyclic aldehydes in the presence of zinc chloride at room temperature. Spectroscopic data were obtained using the following instruments: Fourier transform infrared spectra (KBr discs, 4000-400 cm-1) by Shimadzu IR-408 Perkin-Elmer 1800 instrument; 1H NMR and 13C NMR spectra by Bruker Avance-II 400 MHz using DMSO-d6 as a solvent containing TMS as the internal standard.Results:To continue our ongoing studies to synthesize heterocyclic and pharmaceutical compounds by mild, facile and efficient protocols, herein we wish to report our experimental results on the synthesis of acrylonitrile derivatives, using various aromatic/heterocyclic aldehydes and p-nitrophenylacetonitrile in the presence of zinc chloride in ethanolic media at room temperature. Some of the new compounds were tested for their human serum albumin activity (HSA) while a study of interaction with HSA protein was performed for compounds 3a and 3b. The results show that compound 3b binds tightly to HSA as compared to compound 3a.Conclusion:It can be concluded that acrylonitrile derivatives can be synthesized by an efficient method via the reaction of p-nitrophenylacetonitrile with aromatic/heterocyclic aldehydes by the use of zinc chloride as an effective solid catalyst. The remarkable features of this procedure include excellent yields (90-95%), short reaction period (30 min.), moderate reaction environment, easy workup procedure and managing of the catalyst. This method may find a wide significance in organic synthesis for the synthesis of the Z-acrylonitrile.

To study the interaction of the series of pyridinium based gemini surfactants (GS) (referred to as m-Py-m, m = 14, 16); 4,4′-(propane-1,3-diyl)bis(1-(2-(tetradecyloxy)-2-oxoethyl) dipyridinium chloride (14-Py-14), and 4,4′-(propane-1,3-diyl) bis(1-(2-(hexadecyloxy)-2-oxoethyl)dipyridinium chloride (16-Py-16) with bovine serum albumin (BSA), various physicochemical and spectroscopic tools such as tensiometry, steady-state fluorescence, synchronous fluorescence, pyrene fluorescence, UV–visible, far-UV circular dichroism (CD) were utilized at physiological pH (7.4) and 298 K in combination with computational molecular modeling analysis. The tensiometric results show significant modifications in interfacial and thermodynamic parameters for m-Py-m GS upon BSA combination, deciphering the gemini surfactant-BSA interaction. Steady-state fluorescence analysis evaluates the structural alterations of BSA with the addition of m-Py-m GS. The plots of Stern-Volmer, modified Stern-Volmer, and thermodynamic parameters were used to determine the binding type of m-Py-m GS to BSA. The synchronous fluorescence spectra state a mild effect of gemini surfactants on the emission intensity of tyrosine (Tyr) residues, on the other hand, tryptophan (Trp) residues showed a significant effect. Post addition of GS, the plot of pyrene fluorescence reveals the mild micropolarity fluctuations via the probe (pyrene) molecules encapsulated in BSA. UV–visible experiments support the complex formation between the BSA and m-Py-m GS. Far-UV CD measurements revealed the modifications in the secondary structure of protein produced by m-Py-m GS. Furthermore, we also used the computational molecular modeling for attaining deep insight into BSA and m-Py-m GS binding and the results are supported with our experimental results.

An efficient procedure for the one-pot synthesis of 4-arylmethylene-3- methylisoxazol-5-ones from ethyl acetoacetate, hydroxylamine hydrochloride, and various aromatic aldehydes using sodium acetate as a safe, clean, and green catalyst in ethanol is reported. This simple, synthetic and eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (90–95% yield), high purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis and, more notably, it improved the selectivity for (Z)-isoxazol-5-ones derivatives. By performing DFT calculations, it was found that the (Z)-isomer of compound 4a is stabilized by 6.54 kcal mol−1 more than the (E)-isomer and The Z-isomer of 4g is also more stable, by 4.36 kcal mol−1. All of the compounds were tested for interaction study with ct-DNA. Compounds 4a and 4b shows the most effective binding affinity with ct-DNA in comparison of other synthesized compounds. The interaction studies of compound 4a and 4b with ct-DNA showed groove binding interaction (non-intercalation) with both compounds. On the other hand, compound 4a (K = 5.9 × 105 M−1) shows higher binding affinity to the ct-DNA than compound 4b (K = 4.5 × 105 M−1). The molecular modeling results illustrated that compound 4b strongly binds to groove of DNA by relative binding energy of docked structure −6.35 kcal mol−1.

The reaction of o -halobenzoic acid with aniline derivatives and their subsequent cyclization reaction yielded the acridone derivatives. The series of nitro acridone derivatives were prepared by Ullmann condensation in presence of copper as catalyst and were characterized by FTIR, 1 H, 13 C NMR and mass spectra. The structure of 5-nitro-(2-phenyl amino) benzoic acid ( 4 ) was confirmed by X-ray crystallography and was found to crystallize in P 2 1 / c space group. The in vitro efficacy of the compounds for their acetylcholinesterase (AChE) and antimicrobial inhibitory activities have been evaluated against the standard drugs Ampicillin and Gentamicin against Gram positive and Gram negative bacteria. 1,7-Dinitroacridone was found to be the most potent AChE inhibitor (IC 50 = 0.22 μM). Moreover, the compounds have been screened for their antioxidant activity using the DPPH assay. Also, docking study results were found to be in good agreement with the results obtained through in vitro experiments. The docking study further predicted possible binding conformation.