Development of 1-(2-aminophenyl)pyrrole-based amides acting as human topoisomerase I inhibitors

Topoisomerases are ubiquitous enzymes in the human body, particularly involved in cancer development and progression. Topoisomerase I (topoI) performs DNA relaxation reactions by "controlled rotation" rather than by "strand passage." The inhibition of topoI has become a useful strategy to control cancer cell proliferation. Nowadays, different compounds have undergone clinical trials, but the search for new molecular entities is necessary and benefits from medicinal chemistry efforts. Pyrrole-based compounds emerged as promising antiproliferative agents, with particular interest in breast cancer therapy and topoI inhibition. Starting from these observations and based on the scaffold-hopping approach, we developed a small library of 1-(2-aminophenyl)pyrrole-based amides (7a-f) as new anticancer agents. Tested on a panel of cancer cell lines, 7a-f displayed the most interesting profile in MDA-MB-231 cells, where the most active compounds, 7d-f, were able to induce death by apoptosis. Direct enzymatic assays and docking simulations on the topoI active site (PDB: 1A35) revealed the inhibitory activity and potential binding site for the newly developed 1-(2-aminophenyl)pyrrole-based amides.

Development of Quinazolinone Derivatives as Modulators of Virulence Factors of Pseudomonas aeruginosa Cystic Fibrosis Strains

Pseudomonas aeruginosa (PA), one of the ESKAPE pathogens, is an opportunistic Gram-negative bacterium responsible for nosocomial infections in humans but also for infections in patients affected by AIDS, cancer, or cystic fibrosis (CF). Treatment of PA infections in CF patients is a global healthcare problem due to the ability of PA to gain antibiotic tolerance through biofilm formation. Anti-virulence compounds represent a promising approach as adjuvant therapy, which could reduce or eliminate the pathogenicity of PA without impacting its growth. Pyocyanin is one of the virulence factors whose production is modulated by the Pseudomonas quinolone signal (PQS) through its receptor PqsR. Different PqsR modulators have been synthesized over the years, highlighting this new powerful therapeutic strategy. Based on the promising structure of quinazolin-4(3H)-one, we developed compounds 7a-d, 8a,b, 9, 10, and 11a-f able to reduce biofilm formation and the production of virulence factors (pyocyanin and pyoverdine) at 50 µM in two PA strains responsible for CF acute and chronic infections. The developed compounds did not reduce the cell viability of IB3-1 bronchial CF cells, and computational studies confirmed the potential ability of novel compounds to act as potential Pqs system modulators.