A natural product inspired fragment-based approach towards the development of novel anti-bacterial agents

The discovery of new antibiotics with novel modes of action to combat antimicrobial resistance (AMR) is of vital importance. The natural product simocyclinone D8 (SD8) is a potent inhibitor of DNA gyrase. Its bi-functional structure and novel mode of action serve as an inspiring lead for antibiotic development. Herein we describe a proof of principle fragment-based approach towards the development of a new class of coumarin-quinolone hybrids. We demonstrate that the coumarin moiety is required for the observed inhibitory activity (IC50 ~3 M) of the hybrid compound, which is in part mediated through stabilisation of a cleaved-DNA intermediate.