Antibodies were raised to a 1-benzazepine hapten (I) and the properties of 2 of the strongly binding clones, designated C3 and C5, as catalysts examd. Neither antibody catalyzed the reaction for which they were first generated, electrophilic substitution in the benzene ring, but C3 catalyzed the hydrolysis of an aralkyl 4-nitrophenyl ester with a rate enhancement of >106 compared with the background solvolysis rate. The mechanism of the hydrolysis reaction seems to involve general base catalysis on the basis of chem. modification expts. and isotope effects on the reaction rate in D2O. The possibility that C3 might catalyze other reactions (elimination, deuterium exchange, and epoxide opening) was investigated but no other reactions were obsd. In contrast, C5 catalyzed none of the reactions investigated. The properties of the 2 antibodies are discussed with respect to their ability to bind compds. structurally related to the hapten.
|Number of pages||7|
|Journal||Journal of the Chemical Society, Perkin Transactions 1|
|Publication status||Published - 1992|
- 4-nitrophenyl ester
- catalytic antibody
- ammonium hapten