A series of substituted 9, 10-dihydroxyhexahydrobenzo [f] thieno [c] quinolines (TB [f] Q), varying with respect to the position of the thiophene relative to the benzo [f] quinoline core and the nature and position of the substituent on the thiophene, were prepared and evaluated for their affinity and selectivity for the dopamine D1-like receptor. The thieno [3, 2- c] B [f] Q regioisomers bearing a small alkyl (C1-C3) substituent at the 2 position were ...