Nocathiacin analogs: Synthesis and antibacterial activity of novel water-soluble amides.

Novel water-soluble amide analogs were synthesized from nocathiacin I (1) through the formation of the carboxylic acid intermediate followed by coupling to primary or secondary amines. Several compounds with potent antibacterial activity and adequate water solubility were identified. Of these, compound 19 was selected for more extensive evaluation because of its excellent in vitro antibacterial activity and in vivo efficacy, as well as clean off-target screening.