The ketone XIII, obtained by Friedel-Crafts reaction of toluene with homoveratroyl chloride, was converted by the Leuckart reaction to the formamido derivative IXb which was used as the starting product for the synthesis of amines IIIb-Vb. Reduction of the ketone XIII gave the alcohol XVI which was treated with hydrogen chloride and afforded the chloro compound XVII. Its substitution reactions with 1-methylpiperazine, 1-(2-hydroxyethyl)piperazine and 1-phenylpiperazine resulted in the piperazines VIb-VIIIb. Acylations of the amine IIIb with acetic anhydride and homoveratroyl chloride gave the amides Xb and XIb which, together with the formamide IXb, were subjected to the Bischler-Napieralski reaction. 3,4-Dihydroisoquinolines XXII-XXIV were obtained and reduced to the 1,2,3,4-tetrahydroisoquinolines XXVb-XXVIIb. Treatment of XXVIIb with formaldehyde afforded the berbine derivative XXVIII. Demethylation of the amine IIIb with hydrobromic acid resulted in the title compound IIIa. Similar demethylations of the dimethoxyamines IVb-VIIIb, XXVb and XXVIb led to the dihydroxyamines IVa-VIIIa, XXVa and XXVIa which are dopamine derivatives. Reaction of Va with benzoyl chloride gave the dibenzoate XXX. The CNS activities of the compounds prepared are of a low degree. Several of them (IIIa-VIa, IIIb-Vb, XXVb) show in higher doses signs of central stimulant action but only for compound IVa an antireserpine effect was proven. The expected anticataleptic activity was found only in a low degree with compound VIIIa; on the contrary, compounds IIIa and XXVa are procataleptogenic. Some compounds (IIIa, IXb, XXVIa, XXVIII) potentiated thiopental. In single cases local anaesthetic, spasmolytic, hypotensive, hypertensive, hypoglycaemic, diuretic and antiarrhythmic effects were observed.
Anticataleptic activity of 2-substituted derivatives of 3(H)-quinazolin-4-one