Synthesis and biological evaluation of 1-(4-hydroxy-2-oxo-2H-1-benzopyran-3-yl)pyridinium hydroxide inner salt derivatives.

Eight 1-(4-hydroxy-2-oxo-2H-1-benzopyran-3-yl)pyridinium hydroxide inner salts were synthesized, and the antibacterial, antifungal, anticoccidial, and anthelmintic activities were determined against different microorganisms, the protozoan Eimeria tenella, and trichostrongyle nematodes. All were noninhibitory to Gram-negative bacteria and the parasites. The pyridine, 4-benzylpyridine, and 2-isoquinoline inner salt derivatives controlled only Rhizoctonia solani of the four genera of fungi challenged.