Volkova_1983_Bioorg.Khim_9_926

Cyclization of polymethylene bischloroethylamines, differing in the methylene chain-length (n = 6 or 10) and the N-substituents (R = CH3 or CH2C6H5), was carried out and the respective aziridinium derivatives were obtained. These derivatives of hexamethonium and decamethonium manifested reversible inhibition (Ki approximately 100-1 microM) and irreversible alkylating activity (kII approximately 10(2) M-1 . min-1) towards acetylcholinesterase from human erythrocytes and horse serum butyrylcholinesterase. Upon varying n and R, the alkylation biomolecular rate constants changed symbately with changes in the reversible inhibition constants. The most potent alkylating agent with respect to acetylcholinesterase (kII 7,8 x 10(2) M-1 . min-1) and butyrylcholinesterase (kII 4,2 . 10(2) M-1 . min-1) was found to be the aziridinium analog of hexamethonium with R = CH2C6H5. Based on the kinetic data, the problem of alkylation of anionic sites in the catalytic and allosteric centers of the two cholinesterases is discussed.