Fused ring heterocyclic analogs of A-81080 (pA(2)=9.9) were synthesize
d and their activities in the rabbit aorta in vitro assay were measure
d. The best compounds (pA(2)=8.6) in series 1 had R(1)=Et, R(2)=H, W=Z
=C-H, and Y=C-Ome or C-COOH. In series 2, the best compound (pA(2)=8.3
) had R(1)=Et, R(2)=H, W=N-Me, X=C-H, and Y=N.