The synthesis and properties of phenolic Schiff bases based on 1,8-naphthyridine

Two new phenolic Schiff bases 1 and 2 based on 1,8-naphthyridine were synthesized. The phenomena of ethanolic solutions of compounds 1 and 2 upon adding sodium hydroxide ethanolic solutions, and of the above solutions in air for some time have been studied by UV–vis absorption spectra. Especially, the exact structures of 1b and 2b have also been studied.