Driven by the appearance of antibiotic-resistant bacterial pathogens, there is an ever-pressing need for new antibiotics. Complete genome sequencing of many microbial species has highlighted, during the last decade, a large number of potential molecular targets. Among them, nicotinamide adenosine dinucleotide kinase (NAD kinase) is a ubiquitous enzyme involved in the last step of NADP biosynthesis. NAD(P) biosynthesis is a promising, albeit relatively unexplored, target pathway for the development of novel antimicrobial agents. Thanks to significant functional and structural characterization, bacterial NAD kinases can be regarded as novel and attractive for the development of selective antibacterial drugs. We have recently identified following a « target-guided synthesis » approach, a series of micromolar inhibitors of NAD kinase. Some showed promising bactericidal activities on Staphylococcus aureus. A patent was deposited protecting a first family of nucleoside derivatives. In this project, we aim to demonstrate the antibacterial activity of our compounds in vivo using a mouse model of staphylococcal infection. We will also confirmed in vitro the mechanism of action and validate NAD kinase as the actual target of these new antibacterial series. In parallel, biological activity will be improved by chemical optimization of our current hits. All together these data will strengthen our results recently patented (EP 10290679.9).