* To whom correspondence should be addressed.
Received January 20, 2000; Revision received February 21, 2000
Urethane type derivatives of ethylene diamine (EDA) were synthesized and tested as inhibitors of rat liver mitochondrial monoamine oxidase (MAO) A and B. The nature of the aromatic ring and the position of substituents in it were crucial for manifestation of the inhibitory activity. 3,4- and 2,4-Chlorobenzyloxycarbonyl-EDA derivatives were the most potent MAO A inhibitors. The inhibition of both MAO A and to a lesser extent MAO B depended on preincubation time with these inhibitors. The activity of both enzymes did not recover completely after repeated sedimentation and resuspension of inhibitor-treated mitochondria. The data suggest that these compounds exhibit properties of tight-binding reversible inhibitors of MAO A and B. The development of a new generation of MAO inhibitors causing simultaneous reversible nonselective inhibition of MAO A and B must meet one important criterion, the same type of inhibition of both the enzymes.
KEY WORDS: monoamine oxidase, reversible inhibitors of monoamine oxidase, urethane type derivatives of ethylene diamine