2-Aminothiophene-3-carboxylates and carboxamides as adenosine A1 receptor allosteric enhancers.

Three series of 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene and 2-amino-5,6,7,8-tetrahydrocyclohepta[b]thiophenes with 3-carboxylates and carboxamides have been prepared using the Gewald synthesis and evaluated as A(1)AR allosteric enhancers. The structure-activity relationships of these classes of compound are described. A number of compounds, notably 7b, are more potent and efficacious than PD81,723 (1).