title: Antibacterial activities of Groebke-Blackburn-Bienaymé-derived imidazo[1,2-a]pyridin-3-amines.
abstract: We sought to explore the imidazo[1,2-a]pyridin-3-amines for TLR7 (or 8)-modulatory activities. This chemotype, readily accessed via the Groebke-Blackburn-Bienaymé multi-component reaction, resulted in compounds that were TLR7/8-inactive, but exhibited bacteriostatic activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). To investigate the mechanism of antibacterial activity of this new chemotype, a resistant strain of S. aureus was generated by serially passaging the organism in escalating doses of the most active analogue. A comparison of minimum inhibitory concentrations (MICs) of known bacteriostatic agents in wild-type and resistant strains indicates a novel mechanism of action. Structure-activity relationship studies have led to the identification of positions on the scaffold for additional structural modifications that should allow for the introduction of probes designed to examine cognate binding partners and molecular targets, while not significantly compromising antibacterial potency.
authors.affiliation: Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence, KS 66047, USA.
authors.forename: Nikunj M
authors.initials: NM
authors.lastname: Shukla
authors.forename: Deepak B
authors.initials: DB
authors.lastname: Salunke
authors.forename: Euna
authors.initials: E
authors.lastname: Yoo
authors.forename: Cole A
authors.initials: CA
authors.lastname: Mutz
authors.forename: Rajalakshmi
authors.initials: R
authors.lastname: Balakrishna
authors.forename: Sunil A
authors.initials: SA
authors.lastname: David
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry* / Q000494:pharmacology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D011725:Pyridines / Q000737:chemistry* / Q000494:pharmacology*; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D007093:Imidazoles; D011725:Pyridines