Synthesis and specific nootropic activity of (-)-cytisine derivatives with carbamide and thiocarbamide moieties in their structure
N-(methylcytisinyl)-N-substituted ureas, N-substituted cytisine-12- carbamides, and cytisine-12- thiocarbamide were prepared by reaction of (-)-cytisine with urea and thiourea and of (-)-cytisine and its 12-N-methyl-3-amino derivative with isocyanates. Their specific nootropic activity was studied in vivo. The therapeutic index was determined for the lead compound. Promising candidates for further pharmacological testing were found.