Résumé: Four 4-phenyldiazenyl phenyl aminophosphonates were successfully synthesized using an eco-friendly one-pot Kabachnik-Fields reaction. The reaction involved aromatic aldehydes, 4-(Phenyldiazenyl) aniline, and diethylphosphite, with Ni(SO4).6H2O (5 mol%) serving as an efficient catalyst. Conducted at room temperature under solvent-free conditions within 20 min, the reaction yielded excellent chemical results, with up to 90 % yields. The compounds underwent characterization through IR, UV-vis, NMR (1H, 13C, 31P), and HRMS. The antibacterial activity of the synthesized molecules was evaluated against two Gram-negative bacteria (Escherichia coli ATTC 25922, Pseudomonas aeruginosa ATTC 27853) and the Gram-positive bacterium (Staphylococcus aureus ATTC 25923) at different compound concentrations (32-128 µg/ml) compared to Cefixime. The results revealed significant antibacterial activity of molecules 4b, 4c and 4d against the two Gram-negative bacteria and 4b against S. aureus, with a minimum inhibitory concentration (MIC) of 0.5 µg/mL, surpassing the reference drug. DFT calculations at B3LYP 6-311G (2d, p) basis set were employed for geometry optimization, stability and reactivity studies, including HOMO/LUMO, ΔEGAP, dipole moment, electronegativity, electrophilicity, and calculated thermodynamic descriptors (Enthalpy and Gibbs Free Energy). The molecular docking studies confirmed strong interactions between the synthesized compounds and proteins, with binding affinities ranging from -9.6 to -6.8 kcal/mol. Notably, diethyl (4-biphenyl (4-phenyldiazenyl) phenylamino) methylphosphonate (4b) demonstrated the highest efficiency, making it a promising antibacterial candidate according to both experimental and computational assessments.

Résumé: The G-protein coupled receptors (GPCRs) form a large protein family in the human genome that have been widely studied and classified into classes and phylogenetic subfamilies. However, there still exist orphan GPCRs that are not classified in any of the known subfamilies and new bioinformatics approaches are still needed to address this issue. One of the interesting features of GPCRs is that a large proportion of these proteins are encoded by intronless genes. In this work, we are interested in the study of Rhodpsin-like GPCRs proteins encoded by this kind of genes. After a manual validation of their gene structure, we studied some of their properties including the number of exons, chromosomal location and protein length. The same trend was found for intronless GPCRs as compared to total GPCRs, particularly the uneven chromosomal distribution with a large number (one third) of GPCRs on chromosomes 1 and 11. The proportion of intronless GPCRs among all Rhdopsin-like GPCRs was estimated to about 26% which is significantly less than previously reported. Significant differences in protein length were found between subfamilies. We then used composition properties of DNA and protein sequences to classify intronless Rhodopsin-like GPCRs. Principal component analysis was used to identify key variable and then a discriminant analysis was used to compute discriminant functions that best separates the phylogenetic subfamilies. We found that the most important features to separates the groups is the proportion of aromatic amino acids in protein sequence and the contrast between (A+T) versus (G+C) in coding sequence. These functions are finally used to classify fourteen putative or unclassified GPCRs.