Marcia Pérez-Fehrmann

Antimicrobial resistance (AMR) remains a major threat to modern medicine, fueled by the excessive use of antibiotics and the spread of multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). In this study, we designed and synthesized a series of 2-aryl-4-aminoquinazoline derivatives bearing an aminoalkylimidazole linker, combining two pharmacophoric motifs associated with antimicrobial activity. Starting from anthranilamide, the compounds were prepared in three straightforward steps, affording good yields and high purity. Their structures were confirmed by FT-IR spectroscopy, ¹H and ¹³C nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS). Biological evaluation showed that series 5 exhibited strong selectivity toward S. aureus, with compounds 5c and 5d displaying minimum inhibitory concentrations (MICs) between 2.2 and 4.4 µM. No significant activity was observed against other tested strains. Cytotoxicity assays in HepG2 cells revealed moderate to low inhibition. Molecular docking indicated preferential binding to dihydrofolate reductase (DHFR) and relevant interactions with topoisomerase IV, resembling reference inhibitors. ADME analysis predicted favourable absorption, blood–brain barrier permeability, and compliance with Lipinski’s rules.

The synthesis of (E)-1-(1-benzyl-5-methyl-1H-1,2,3-triazol-4-yl)-3-phenyl-2-propen-1-one derivatives was carried out in two steps, using benzylic chloride derivatives as starting material. The structural determination of intermediates and final products was performed by spectroscopic methods: infrared spectroscopy, nuclear magnetic resonance spectroscopy and mass spectrometry (IR, NMR, and MS). In vitro evaluation of cytotoxic activity on adherent and non-adherent cells showed that triazole chalcones exhibited significant activity against three of the five cell lines studied: non-Hodgkin lymphoma U937, glioblastoma multiform tumor T98G, and gallbladder cancer cells Gb-d1. In contrast, the cytotoxic activity observed for cervical cancer HeLa and gallbladder adenocarcinoma G-415 was considerably lower. Additionally, in the cell lines where activity was observed, some compounds demonstrated an In vitro inhibitory effect superior to that of the control, paclitaxel. Molecular docking studies revealed specific interactions between the synthesized ligands and therapeutic targets in various cell lines. In U937 cells, compounds 4a and 4c exhibited significant inhibition of vascular endothelial growth factor receptor (VEGFR) kinase, correlating with their biological activity. This effect was attributed to favorable interactions with key residues in the binding site. In T98G cells, compounds 4r and 4w showed affinity for transglutaminase 2 (TG2) protein, driven by their ability to form hydrophobic interactions. In Gb-d1 cells, compounds 4l and 4p exhibited favorable interactions with mitogen-activated protein kinase (MEK) protein, similar to those observed with the known inhibitor selumetinib. In HeLa cells, compounds 4h and 4g showed activity against dihydrofolate reductase (DHFR) protein, driven by hydrogen bonding interactions and favorable aromatic ring orientations. On the other hand, compounds 4b and 4t exhibited no activity, likely due to unfavorable interactions related to halogen substitutions in the aromatic rings.

New iodinated 4-(3H)-quinazolinones 3N-substituted with antitumor activity and 3D-QSAR and molecular docking studies as dihydrofolate reductase (DHFR) inhibitors.

A new series of diarylhydrazones derived from 2,4-dinitrophenylhydrazine were synthesized via condensation with aromatic aldehydes whose structures have been determined by mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectra. Yields were 50-99%. All compounds were screened in vitro for their antifungal activity. Preliminary results indicated that compounds 3g and 3h exhibited promising antifungal potency. Understanding of the structure of these compounds establishes a preliminary structure-activity relationship to form the basis of further investigation.