Abstract
The behavior of 4-amino-5-carboxy-2-methylpyrimidine (ACMP) was compared with those of 2-aminoisonicotinic acid (ANA) and 2-aminoisonicotinic acid (AINA) in water. The behaviors of these compounds were investigated spectrophotometrically by comparison with those of the corresponding ethyl ester and 1-methyl betaine. The Edsall-Blanchard equation was used to evaluate the equilibrium constants, Kz between zwitterion from and uncharged from in water. The evaluated Kz values indicated that ACMP, ANA and AINA existed almost completely in the zwitterion form in water, respectively. This result was in good agreement with the spectrophoto-chemical observations.
