Convenient and Efficient Method for Synthesis of Bis‐Hetaryl Ketones and Evaluation of Their Antimicrobial Activity

Sodium 1‐aryl‐3‐(3‐(ethoxycarbonyl)‐5‐methyl‐1H‐pyrazol‐4‐yl)‐3‐oxoprop‐1‐en‐1‐olate was used as precursor for the preparation of some novel derivatives of various fused azolotriazine ring systems via coupling reactions with hetaryldiazonium salts. Hydrazinolysis of the latter products yielded the corresponding pyrazolopyridazine derivatives. The structures of the products were established by their spectral data and elemental analyses. The antibacterial and antifungal activities of some of the new products were also evaluated.     

Synthesis and characterization of some novel bis‐thiazoles

The bis‐thiosemicarbazone derivative 3 was prepared and reacted with N‐aryl‐2‐oxopropane hydrazonoyl chloride 4a‐g and ethyl (N‐arylhydrazono)chloroacetate 7a‐e in absolute ethanol in the presence of triethylamine at reflux afforded a new series of thiazoles 6a‐g and 9a‐e , respectively. Also, thiosemicarbazone derivative 3 was reacted with N′‐phenylbenzohydrazonoyl chloride 10 to give the respective bis‐thiadiazole derivative 12 . Moreover, the reaction of 3 with a number of haloketones and haloesters furnished the respective bis‐thiazole derivatives 14 , 16 , 18 , and 20 . The mechanisms that account for formation of products 6 , 9 , and 12 were discussed. Also, the molecular structure of the synthesized compounds was illustrated by spectroscopic and elemental analysis.     

Structural Elucidation and Antimicrobial Evaluation of Novel [1,2,4]Triazolo[4,3‐a]pyrimidines and Pyrido[2,3‐d][1,2,4]triazolo[4,3‐a]pyrimidinones

1,3‐Di(thiophen‐2‐yl)prop‐2‐en‐1‐one ( 1 ) was utilized in the synthesis of 4,6‐di(thiophen‐2‐yl)‐3,4‐dihydropyrimidine‐2(1H)‐thione ( 2 ) and 5,7‐di(thiophen‐2‐yl)‐2‐thioxo‐2,3‐dihydropyrido[2,3‐d]pyrimidin‐4(1H)‐one ( 4 ). The latter thiones were used in the synthesis of two new series of [1,2,4]triazolo[4,3‐a]pyrimidines 10a – i and pyrido[2,3‐d][1,2,4]triazolo[4,3‐a]pyrimidinones 5a – i via reaction with the appropriate hydrazonoyl halides using triethylamine as a basic catalyst in dioxane. The mechanism of formation of the synthesized compounds was discussed, and the assigned structure was established via microanalysis, spectral data (infrared, ¹H NMR, and Mass), and density functional calculations. Moreover, the newly synthesized products were evaluated for their antimicrobial activities, and the results show that some derivatives have been well with mild activities. Finally, quantum chemistry calculations confirmed the mechanism and structure of the products.     

A theoretical study of substitution effects on halogen–π interactions

Ab initio calculations are performed to analyse the existence of intermolecular halogen···π interactions in NCX complexes with YC≡CY, where X = Cl, Br and Y = H, CN, F, Cl, OH, NH₂, and CH₃. Molecular geometries and interaction energies of the complexes are investigated at the MP2/aug-cc-pVTZ level of theory. Our results indicate that the interaction energies for the NCX···YC≡CY complexes lie in the range between ?0.5 and ?5.9 kcal/mol. The physical nature of the interactions is studied using symmetry-adapted perturbation theory (SAPT). The stability of the X···π interactions is predicted to be attributable mainly to electrostatic and dispersion effects.     

Synthesis,Molecular Docking Study,and Cytotoxic Activity against MCF Cells of New Thiazole–Thiophene Scaffolds

Investigating novel compounds that may be useful in designing new, less toxic, selective, and potent breast anticancer agents is still the main challenge for medicinal chemists. Thus, in the present work, acetylthiophene was used as a building block to synthesize a novel series of thiazole-bearing thiophene derivatives. The structures of the synthesized compounds were elucidated based on elemental analysis and spectral measurements. The cytotoxic activities of the synthesized compounds were evaluated against MCF-7 tumor cells and compared to a cisplatin reference drug, and against the LLC-Mk2 normal cell line using the MTT assay, and the results revealed promising activities for compounds 4b and 13a. The active compounds were subjected to molecular modeling using MOE 2019, the pharmacokinetics were studied using SwissADME, and a toxicity radar was obtained from the biological screening data. The results obtained from the computational studies supported the results obtained from the anticancer biological studies.     

Study of the migration of additives from plasticized PVC

The aim of this paper is to study the interactions between packaging and food. For that purpose, additives were first characterized. Kinetic studies of their specific migrations have been carried out by using different analytical methods such as gas chromatography, Fourier transform infrared spectroscopy, atomic absorption spectrometry and differential scanning calorimetric analysis. The influence of various parameters such as temperature, agitation, nature of food simulant and initial concentration of plasticizer was considered.