Studies on Thiophene Derivatives. I. Syntheses of 2-Amino-1, 1-di (2-thienyl) alkanols

It was found that 3-piperidino-1, 1-di (2-thienyl) butene prepared by Adamson possessed an antitussive action. The compound has one amino group at the 3-position, and one double bond between 1 and 2. However, ephedrine used as an antitussive for a long time has one amino group at 2-position and a hydroxyl group at 1-position. Therefore, 2-amino-1, 1-di (2-thienyl) propanols and 2-amino-1, 1-di (2-thienyl)-ethanols which have one amino group at 2-position and hydroxyl group at 1-position were synthesized, in order to investigate the structure-activity relationship of the antitussive. The compounds were synthesized by the condensation of 1-aminoalkane-1-carboxylic acid esters and thiophene (the lithium method).