Bencyclane fumarate (I) was decomposed in aqueous buffer solution from pH 1.2 to 6.3 in order to examine its stability and mechanism of hydrolysis. It was found that I was hydrolyzed with pseudo first-order kinetics, and the pH-rate profile was a straight line of slope-1. The activation energy (Ea) was calculated to be 33.0 kcal/mol from Arrhenius plots. Further examination of the decomposition mechanism through kinetic analysis suggested a new ...