Successful application of serum shift prediction models to the design of dual targeting inhibitors of bacterial gyrase B and topoisomerase IV with improved in vivo efficacy

A series of dual targeting inhibitors of bacterial gyrase B and topoisomerase IV were identified and optimized to mid-to-low nanomolar potency against a variety of bacteria. However, in spite of seemingly adequate exposure achieved upon IV administration, the in vivo efficacy of the early lead compounds was limited by high levels of binding to serum proteins. To overcome this limitation, targeted serum shift prediction models were generated for each subclass of interest and were applied to the design of prospective analogs. As a result, numerous compounds with comparable antibacterial potency and reduced protein binding were generated. These efforts culminated in the synthesis of compound 10, a potent inhibitor with low serum shift that demonstrated greatly improved in vivo efficacy in two distinct rat infection models.