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 A1AR 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).
![2-amino-N-(4-chlorophenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide Structure](https://image.chemsrc.com/caspic/211/69438-16-0.png)