Synthesis and copper-dependent antimycoplasmal activity of 1-amino-3-(2-pyridyl)isoquinoline derivatives. 1. Amides.

In order to investigate the antimycoplasmal activity of compounds structurally related to 2,2'-bipyridyl, a series of both aliphatic and aromatic amides derived from 1-amino-3-(2-pyridyl)isoquinoline were synthesized. The most active compounds appeared to be as active as Tylosin, an antimycoplasmal therapeutic that is used in veterinary practice, in the presence of a small nontoxic amount of copper. Furthermore, it was found that antimycoplasmal activity depends on the hydrophobic fragmental value of amide residue. A quantitative structure-activity relationship established the optimal hydrophobic fragmental value of the amide residue to be 0.30.