Abstract
1-Phenethyl-and 1-[2-(N-alkylanilino)ethyl]-3-alkyl-4-piperidinepropionates were synthesized for physiological evaluation as analgesics. Phenethylamine was condensed with formaldehyde and various alkylmalonic acids, followed by decarboxylation and esterification, to furnish the corresponding 2-alkyl-3-phenethylaminopropionates, which were also prepared from the same amine and 2-alkylacrylates. These were then converted to 3, 3'-(phenethylimino) dipropionic ester derivatives, which were condensed by the Dieckmann method and the crude keto esters were directly submitted to ketonic fission. 1-Phenethyl-3-alkyl-4-piperidinones thus obtained formed a viscous oil, which was allowed to react with phenyllithium and the products were treated with propionic anhydride, to give the ultimate compounds. From N-alkyl-N-Phenylethylenediamine in place of phenethylamine the corresponding piperidinol propionates were similarly prepared. The results of the pharmacological examination of these compounds were described briefly.
