Reactions of Heterocyclic beta-enaminoester, Synthesis and Antimicrobial Activity of Novel PyrimidinoPyrimidine Derivatives

In this work the corresponding 4-amino-6-pyridyl-2-phenyl-5-carbethoxypyrimidine (3) was synthesized through a one-pot, three-component reaction of pyridine-3-carbaldehyde, ethyl cyanoacetate and benzamidine hydrochloride in the presence of TEA in refluxing ethanol-DMF mixture. The synthesized pyrimidine (3) was directly transformed to medicinally important pyrimido[4,5-d]pyrimidine derivatives. All the synthesized products were tested and evaluated as antimicrobial agents. Keywords: Pyrimidine-5-ethyl carboxylate derivative, Pyrimido[4,5-d]pyrimidine, Chloroacetyl chlorid

Pyridyl thiosemicarbazide: synthesis, crystal structure, DFT/B3LYP, molecular docking studies and its biological investigations

Abstract N-(pyridin-2-yl)hydrazinecarbothioamide has been synthesized and characterized by single-crystal X-ray and spectroscopic techniques. Furthermore, its geometry optimization, calculated vibrational frequencies, non-linear optical properties, electrostatic potential and average local ionization energy properties of molecular surface were being evaluated using Jaguar program in the Schrödinger’s set on the basis of the density functional concept to pretend the molecular geometry and predict properties of molecule performed by the hybrid density functional routine B3LYP. Furthermore, the docking study of N-(pyridin-2-yl)hydrazinecarbothioamide were applied against negative Escherichia coli bacterial and gram positive Staphylococcus aureus bacterial strains by Schrödinger suite program using XP glide protocol

Confirmed Mechanism for 1,8-Diaminonaphthalene and Ethyl Aroylpyrovate Derivatives Reaction, DFT/B3LYP, and Antimicrobial Activity of the Products

Two new series of perimidine derivatives were prepared from the reaction of 1,8-diaminonaphthalene with ethyl aroylpyrovate followed by coupling for the products. The structures, the mechanism, and the tautomeric forms of the products have been discussed on the basis of spectral data aided with the computational study. Applying Guassian09 software, the reaction mechanism was assured. The energy contents were computed after optimization for all proposed structures. The likely extracted compound has a reduced heat during formation and internal energy which coincides with experimental outcomes. The antimicrobial activity of all products was screened, and their results indicated the presence of five derivatives more potent than the reference drugs used. The simulation procedure was executed by Autodock 4.2 tools over the expected compounds yielded (12 and 21). This computational technique asserts on the drug behavior inside the causative organism proteins. The organisms here match with that used in the antimicrobial and antifungal study

Synthesis, Modeling Study and Antioxidants Activity of New Heterocycles Derived from 4-Antipyrinyl-2-Chloroacetamidothiazoles

The present work reports the preparation of twelve new heterocyclic scaffolds containing an antipyrinyl-thiazole hybrid through the reaction of 4-antipyrinyl-2-chloroacetamido-thiazoles 1 and 6 with various types of nucleophiles, namely; ethyl thioglycolate, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, ammonium thiocyanate, malononitrile, and salicylaldehyde. The constructed compounds were characterized by conventional spectroscopic techniques (IR, 1H NMR, 13C NMR, and mass analysis). A DFT method (material studio package) was used to predict the geometry, bond lengths, bond angles, and dipole moments as well as other global chemical reactivities of the constructed antipyrinyl-thiazole compounds. Also, their semi-core pseudopods calculations (dspp) were carried out with DNP (double numerical basis sets plus polarization functional) to predict the properties of materials. In addition, the antioxidant activity of these antipyrinyl-thiazole scaffolds has been screened by the ABTS method. The results indicated that 2-(4-antipyrinylthiazolylamino)-5-substituitedbenzylidene-thiazol-4(5H)-ones 10b and 10c exhibited the best antioxidant activity with a percentage inhibition of 85.74% and 83.51%, respectively

Design, Synthesis and DFT/DNP Modeling Study of New 2-Amino-5-arylazothiazole Derivatives as Potential Antibacterial Agents

A new series of 2-amino-5-arylazothiazole derivatives has been designed and synthesized in 61–78% yields and screened as potential antibacterial drug candidates against the Gram negative bacterium Escherichia coli. The geometry of the title compounds were being studied using the Material Studio package and semi-core pseudopods calculations (dspp) were performed with the double numerica basis sets plus polarization functional (DNP) to predict the properties of materials using the hybrid FT/B3LYP method. Modeling calculations, especially the (EH-EL) difference and the energetic parameters revealed that some of the title compounds may be promising tools for further research work and the activity is structure dependent

Potential COVID-19 Drug Candidates Based on Diazinyl-Thiazol-Imine Moieties: Synthesis and Greener Pastures Biological Study

A novel series of 1-aryl-N-[4-phenyl-5-(arylazo)thiazol-2-yl)methanimines has been synthesized via the condensation of 2-amino-4-phenyl-5-arylazothiazole with various aromatic aldehydes. The synthesized imines were characterized by spectroscopic techniques, namely 1H and 13C-NMR, FTIR, MS, and Elemental Analysis. A molecular comparative docking study for 3a–f was calculated, with reference to two approved drugs, Molnupiravir and Remdesivir, using 7BQY (Mpro; PDB code 7BQY; resolution: 1.7 A°) under identical conditions. The binding scores against 7BQY were in the range of −7.7 to −8.7 kcal/mol for 3a–f. The high scores of the compounds indicated an enhanced binding affinity of the molecules to the receptor. This is due to the hydrophobic interactions and multi-hydrogen bonds between 3a–f ligands and the receptor’s active amino acid residues. The main aim of using in silco molecular docking was to rank 3a–f with respect to the approved drugs, Molnupiravir and Remdesivir, using free energy methods as greener pastures. A further interesting comparison presented the laydown of the ligands before and after molecular docking. These results and other supporting statistical analyses suggested that ligands 3a–f deserve further investigation in the context of potential therapeutic agents for COVID-19. Free-cost, PASS, SwissADME, and Way2drug were used in this research paper to determine the possible biological activities and cytotoxicity of 3a–f

Synthesis, Modeling Study and Antioxidants Activity of New Heterocycles Derived from 4-Antipyrinyl-2-Chloroacetamidothiazoles

The present work reports the preparation of twelve new heterocyclic scaffolds containing an antipyrinyl-thiazole hybrid through the reaction of 4-antipyrinyl-2-chloroacetamido-thiazoles 1 and 6 with various types of nucleophiles, namely; ethyl thioglycolate, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, ammonium thiocyanate, malononitrile, and salicylaldehyde. The constructed compounds were characterized by conventional spectroscopic techniques (IR, 1H NMR, 13C NMR, and mass analysis). A DFT method (material studio package) was used to predict the geometry, bond lengths, bond angles, and dipole moments as well as other global chemical reactivities of the constructed antipyrinyl-thiazole compounds. Also, their semi-core pseudopods calculations (dspp) were carried out with DNP (double numerical basis sets plus polarization functional) to predict the properties of materials. In addition, the antioxidant activity of these antipyrinyl-thiazole scaffolds has been screened by the ABTS method. The results indicated that 2-(4-antipyrinylthiazolylamino)-5-substituitedbenzylidene-thiazol-4(5H)-ones 10b and 10c exhibited the best antioxidant activity with a percentage inhibition of 85.74% and 83.51%, respectively