A series of 1-[1-(benzo-1,4-dioxan-2-ylmethyl)-4-piperidinyl]benzimid azolones with various substituents in both aromatic rings have been synthesized and tested for neuroleptic activity (antiapomorphine effects and [3H]spiroperidol binding) as well as extrapyramidal effects (cataleptogenic effect). A strong dependence of activity on the 5-substituent in the benzimidazolone moiety could be demonstrated. Some compounds show a large split between the desired antiapomorphine and the undesired extrapyramidal effect. From these, 1-[1-(benzo-1,4-dioxan-2-ylmethyl)-4-piperidinyl]-5-chlor obenzimidazol-2-one hydrochloride (HR 723), 12, has been selected for further preclinical and toxicological profiling.

No abstract

Because tyrosine and dopa can be regarded as precursors of adrenomedullary hormones and melanin, radioiodinated derivatives of these compounds were tested for their accumulation in the adrenal medulla and in melanomas of various animal species. The highest level of accumulation in the adrenal medulla was attained in mice and rats with iodinated beta-hydroxy-alpha-methyltyramine, and in melanomas of mice with iodinated alpha-methyltyrosine. The results could not be reproduced to the same extent in other species.

No abstract

6 Nomifensine differs from the tricyclic antidepressants by virtue of its effect on the dopaminergic system.