RESUMO
The SARS-CoV-2 pandemic is currently causing an unprecedented global health emergency since its emergence in December 2019. In December 2021, the FDA granted emergency use authorization to nirmatrelvir, a SARS-CoV-2 main protease inhibitor, for treating infected patients. This peptidomimetic is designed with a nitrile warhead, which forms a covalent bond to the viral protease. Herein, we investigate nirmatrelvir analogs with different warheads and their inhibitory activities. In addition, antiviral activities against human alphacoronavirus 229E was also investigated along with a cell-based assay. We discovered that the hydroxymethylketone and ketobenzothiazole warheads were equipotent to the nitrile warhead, suggesting that these analogs can also be used for treating coronavirus infections.
RESUMO
Staphylococcus aureus is the main aetiological agent responsible for the majority of human skin infections. Of particular concern is the methicillin-resistant variety, commonly known as MRSA. The extensive use of the first-line topical antibiotic of choice, mupirocin, has inevitably resulted in the emergence of resistant strains, signalling an urgent need for the development of new antibacterials with new mechanisms of action. In this work, we describe how we designed a novel cationic nonapeptide, containing only leucine and two lysine residues, with potent anti-MRSA activity and a rapid bactericidal mode of action. Coupled to a favourable safety profile towards human skin fibroblasts, we believe nonapeptide 11 has high potential for further development as a mupirocin replacement candidate to treat skin infections caused by MRSA.