Hydrolytic degradation of N,N′-ethylenedimaleimide: Crystal structures of key intermediates and proposed mechanisms

Maleimide groups are used extensively in bioconjugation reactions, but limited mechanistic studies are available regarding their hydrolysis reactions . In this paper, five single-crystal structures related with the reaction of four-step hydrolytic degradation of N,N ′-ethylenedimaleimide have been investigated. On the basis of experimental results, the reaction mechanisms without or with water catalysis are proposed, which could provide some enlightenment into the study of similar hydrolytic degradations.