Proton NMR studies of protonation in pyridazin-3(2H)-one and 6-hydroxypyridazin-3(2H)-one was written by Barlin, Gordon B.;Fenn, M. David. And the article was included in Australian Journal of Chemistry in 1979.Quality Control of 3-Methoxypyridazine This article mentions the following:
A 1H NMR study of protonation in pyridazin-3-ol and pyridazine-3,6-diol revealed that the processes are not simple and suggests that a mobile tautomeric equilibrium may be involved. In the experiment, the researchers used many compounds, for example, 3-Methoxypyridazine (cas: 19064-65-4Quality Control of 3-Methoxypyridazine).
3-Methoxypyridazine (cas: 19064-65-4) belongs to pyridazine derivatives. The pyridazine derivatives are mostly present in biologically active compounds and are also present with different pharmacophores. Pyridazine is bioavailable (especially in the CNS) and can reduce toxicity. Pyridazine is a component of several drug molecules, and the pyridazine pharmacophore has contributed to a variety of pharmacologically active compounds.Quality Control of 3-Methoxypyridazine
Referemce:
Pyridazine – Wikipedia,
Pyridazine | C4H4N2 – PubChem