The reaction of ethyl 2-oxo-2H-chromene-3-carboxylate with hydrazine hydrate

Fragment merging approach for design, synthesis, and biological assessment of urea/acetyl hydrazide clubbed thienopyrimidine derivatives as GSK-3β inhibitors

New thienopyrimidine derivatives were designed and synthesized as GSK-3β inhibitors based on the structure of active binding site of GSK-3β enzyme. In this study, compounds 6b and 6a were found to be moderate GSK-3β inhibitors with IC50s 10.2 and 17.3 μM, respectively. Molecular docking study was carried out by docking the targeted compounds in the binding site of the GSK-3β enzyme using the MOE program. Moreover, ADME study was performed to predict certain pharmacokinetic properties. The results showed that all synthesized compounds may not be able to penetrate the blood brain barrier; so, the chances of CNS side effects are predicted to be low. CYP1D6 is predicted to be inhibited by compounds (5a, 5d, 6a, 9a and 9b), So drug-drug interactions are expected upon administration of these compounds.

Synthesis, Molecular Docking, Dynamics, Quantum-Chemical Computation, and Antimicrobial Activity Studies of Some New Benzimidazole-Thiadiazole Hybrids

In this study, some new compounds, which are 2-aminothiadiazole derivatives linked by a phenyl bridge to the 2-position of the benzimidazole ring, were designed and synthesized as antimicrobial agents. The structures of the compounds were elucidated by ¹H and ¹³C NMR spectroscopy, high-resolution mass spectrometry, and elemental analysis. The antifungal activities of the synthesized compounds were tested on Candida albicans, Candida krusei, Candida glabrata, and Candida parapsilosis. Compound 5f is more active against C. albicans and C. glabrata than standard fluconazole and varicanazole. Compounds were also evaluated for their counteracting activity against Gram-positive Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa and Gram-negative Enterococcus faecalis, Bacillus subtilis, and Staphylococcus aureus. Compounds 5c and 5h had minimum inhibitory concentrations against E. faecalis close to that of the standard azithromycin. Molecular docking studies were performed against Candida species' 14-α demethylase enzyme. 5f was the most active compound against Candida species, which gave the highest docking interaction energy. The stabilities of compounds 5c and 5f with CYP51 were tested using 100 ns molecular dynamics simulations. According to the theoretical ADME calculations, the profiles of the compounds are suitable in terms of limiting rules. HOMO-LUMO analysis showed that 5h is chemically more reactive (represented with the lower ΔE = 3.432 eV) than the other molecules, which is compatible with the highest antibacterial activity result.

Synthesis of new benzimidazole derivatives containing 1,3,4-thiadiazole: their in vitro antimicrobial, in silico molecular docking and molecular dynamic simulations studies

A series of some new benzimidazole-1,3,4-thiadiazoles was synthesized. The structures of target substances were confirmed by using ¹H-NMR and ¹³С-NMR spectroscopy, mass spectrometry and elemental analysis. The synthesized compounds were evaluated for antimicrobial activity against six bacterial strains namely Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (ATCC 27853), Enterococcus faecalis (ATCC 2942), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 29213)and four fungal strains namely Candida albicans (ATCC 24433), Candida krusei (ATCC 6258), Candida parapsilosis (ATCC 22019) and Candida glabrata (ATCC 9). Antimicrobial data revealed that compounds 4f and 4i with MIC of < 0.97 µg/mL were found to be most effective against E. coli. Among the studied molecules, compounds 4f and 4i showed the best antifungal activity with MIC value of 1.95 µg/mL. Additionally, docking studies were performed towards the most promising compounds 4f and 4i, in the active site of DNA gyrase revealing strong interactions. A molecular dynamics (MD) simulation analysis was also used to investigate the dynamic nature, binding interaction, and protein-ligand stability.

Solvent-Free Ring Cleavage Hydrazinolysis of Certain Biginelli Pyrimidines

Certain Biginelli pyrimidines with ester substitution in C5 were subjected to unexpected ring opening upon solvent-free reaction with hydrazine hydrate to give three products: pyrazole, arylidenehydrazines, and urea/thiourea, respectively. The nonisolable carbohydrazide intermediates are formed firstly followed by the intermolecular nucleophilic attack of terminal amino group of hydrazide function on sp2 C6 rather than the sp3 C4 to give the ring adduct which was produced as a final product.

Design, synthesis, biological activities and 3D-QSAR of new N,N'-diacylhydrazines containing 2,4-dichlorophenoxy moieties

A series of new N,N'-diacylhydrazine derivatives were designed and synthesized. Their structures were verified by 1H-NMR, MS and elemental analysis. The herbicidal activities and plant growth regulating activity of these N,N'-diacylhydrazines were evaluated. The herbicidal activity results showed that most of these N,N'-diacyl-hydrazines showed excellent in vivo activities against Echinochloa crus-galli, Digitaria sanguinalis, Brassica napus, Amaranthus retroflerus. Most of them exhibited higher herbicidal activities against dicotyledonous weeds than monocotyledonous weeds. To further investigate the structure-activity relationship, comparative molecular field analysis (CoMFA) was performed on the basis of herbicidal activity data. Both the steric and electronic field distributions of CoMFA are in good agreement in this work.