Congeners of the .alpha. conformer of dopamine derived from octahydrobenz[h]isoquinoline

Abstract

Two synthetic paths were investigated for the preparation of cis and trans 8,9-dioxygenated octahydrobenz[h]isoquinoline ring systems. A sequence involving intramolecular Diels-Alder cyclization of a ring-opened intermediate product of a benzocyclobutene derivative was more satisfactory. The trans-fused isomers of the title compounds are frozen congeners of the .alpha. conformer of dopamine, isomeric with certain other tricyclic heterocycles which elicit a high degree of dopamine agonist activity. The present series of compounds exhibited a very low potency in an assay for dopamine-like actions in cats. A possible reason for this inactivity was suggested.