Abstract: The Zn (11)-catalyzed hydrolysis of 6-carboxy-0-(acetyloxy)-2- pyridinecarboxaldoxime (3) consists of two reaction paths. Rates of the paths were proportional to [Zn (II)][OH-] or to [Zn (II)][OH-]*. On the other hand, catalysis by the Cu (11) ion was not observed in the hydrolysis of 3. The results were compared with those previously obtained for the Cu (I1)-or Zn (11)-catalyzed hydrolysis of O-(acetyloxy)-2- ...