New Schiff-base ligands containing thiophene terminals: Synthesis, characterization and biological activities

Synthesis and Biological Evaluation of New Schiff Bases Derived from 4-Amino-5-(3-fluorophenyl)-1,2,4-triazole-3-thione

The treatment of infectious diseases is a challenging issue faced by the medical community. The emergence of drug-resistant strains of bacteria and fungi is a major concern. Researchers and medical professionals are working to develop new and innovative treatments for infectious diseases. Schiff bases are one a promising class of compounds. In this work, new derivatives were obtained of the 4-amino-5-(3-fluorophenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione reaction, with corresponding benzaldehydes with various substituents at position 4. The antibacterial and antifungal activities of all synthesized compounds were tested. Several new substances have shown moderate antifungal activity against Candida spp. The highest activity directed against C. albicans was shown by compound RO4, with a 4-methoxyphenyl moiety and an MIC value of 62.5 µg/mL. In order to check the toxicity of the synthesized compounds, their effect on cell lines was examined. Additionally, we tried to elucidate the mechanism of the antibacterial and antifungal activity of the tested compounds using molecular docking to topoisomerase IV, D-Alanyl-D-Alanine Ligase, and dihydrofolate reductase.

Novel N-benzyl-2-oxo-1,2-dihydrofuro [3,4-d]pyrimidine-3(4H)-carboxamide as anticancer agent: Synthesis, drug-likeness, ADMET profile, DFT and molecular modelling against EGFR target

A novel compound N-benzyl-2-oxo-1,2-dihydrofuro [3,4-d]pyrimidine-3(4H)-carboxamide (DHFP) was synthesized by addition, rearrangement, and intramolecular cyclization reactions. The three-dimensional geometry of DHFP has been determined by density functional theory calculations in the gas phase. Thus, the geometrical properties of DHFP such as the bond lengths, bond angles, and dihedral bond angles have been determined in the optimized molecular configuration. Also, the HOMO-LUMO energies were calculated. The charge distribution of the DHFP has been calculated by Natural Population Analysis (NPA) approach. NMR and FTIR spectra were calculated and compared with their experimental corresponding to confirm the synthesis of the DHFP. The anticancer activities of the DHFP were also determined on human colon cancer (HT29) and prostate cancer (DU145) cell lines. Molecular docking studies of the DHFP with EGFR tyrosine kinase, which is responsible for cancer cell proliferation and growth, were performed and it was observed that docking interaction took place. The DHFP has the potential to be a drug, as it is determined that DHFP obeys Lipinski's five rules, can cross the blood-brain barrier, and can be rapidly absorbed from the gastrointestinal wall.

Schiff-base ligands containing phenanthroline terminals: Synthesis, characterization, biological activities and molecular docking study

Three new phenanthroline-derived ligands were synthesized by the Schiff base condensation method. The first ligand was the result of 1,10-phenanthroline-2-carboxyaldehyde reaction with 1,4-diaminobutane (L1). The other ligands were obtained 1,6-diaminohexane (L2) and 1,8-diaminooctane (L3) with the phenanthroline aldehyde in separate reactions. The structures of all ligands were elucidated using spectral techniques such as FT-IR, ¹³C NMR, ¹H NMR and LC ESI/MS. The geometric properties of ligands such as bond lengths, bond angles, dihedral angles, electronic properties, HOMO and LUMO energies were calculated by using the Gaussian 09w programme. Ligands were optimized with B3LYP and 6-311++G(2d,p) basis set and NMR and FT-IR spectra were calculated. Experimental and theoretical spectrum data were compared. All of the ligands showed antibacterial activity against Staphylococcus aureus ATCC 25923 and Bacillus cereus ATCC 11778. The anticancer activities of the ligands were also determined against human breast cancer (MCF7) and prostate cancer (DU145) cell lines. In addition, which conformation of the ligands was determined by the theoretical calculations. Docking studies of ligands with bovine serum albumin (BSA) were performed using Autock Tools 1.5.6 programme.