4lp0

Publication Abstract from PubMed

The discovery and optimization of a new class of bacterial topoisomerase (DNA gyrase and topoisomerase IV) inhibitors binding in the ATP domain are described. A fragment molecule, 1-ethyl-3-(2-pyridyl)urea, provided sufficiently potent enzyme inhibition (32 muM) to prompt further analogue work. Acids and acid isosteres were incorporated at the 5-pyridyl position of this fragment, bridging to a key asparagine residue, improving enzyme inhibition, and leading to measurable antibacterial activity. A CF3-thiazole substituent at the 4-pyridyl position improved inhibitory potency due to a favorable lipophilic interaction. Promising antibacterial activity was seen versus the Gram-positive pathogens Staphylococcus aureus and Streptococcus pneumoniae and the Gram-negative pathogens Haemophilus influenzae and Moraxella catarrhalis . Precursor metabolite incorporation and mutant analysis studies support the mode-of-action, blockage of DNA synthesis by dual target topoisomerase inhibition. Compound 35 was efficacious in a mouse S. aureus disease model, where a 4.5-log reduction in colony forming units versus control was demonstrated.

Fragment-to-Hit-to-Lead Discovery of a Novel Pyridylurea Scaffold of ATP Competitive Dual Targeting Type II Topoisomerase Inhibiting Antibacterial Agents.,Basarab GS, Manchester JI, Bist S, Boriack-Sjodin PA, Dangel B, Illingworth R, Sherer BA, Sriram S, Uria-Nickelsen M, Eakin AE J Med Chem. 2013 Oct 29. PMID:24098982^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.