Structure-activity relationships among desmethyl derivatives of neuroleptics and antidepressants for substrate specificty to indolethylamine N-methyltransferase from rabbit lung.

Desmethylperazine (norperazine) and desmethylprochlorperazine (norprochlorperazine), like nor1- and nor2chlorpromazine, are excellent substrates for indolethylamine N-methyltransferase (NMT) and also inhibit the formation of dimethyltryptamine (DMT) from N-methyl-tryptamine (NMT). Nortriptyline and protriptyline, antidepressant compounds which like NMT contain a secondary amino group, also serve as substrates for INMT but lack in inhibitory effect on DMT formation.