.alpha.-Adrenoreceptor reagents. 3. Synthesis of some 2-substituted 1,4-benzodioxans as selective presynaptic .alpha.2-adrenoreceptor antagonists

Abstract
The synthesis and pharmacological activity [in mice and rats] of a series of 2-substituted derivatives of the selective .alpha.2-adrenoreceptor antagonist idazoxan (RX 781094) is described. Substitution in this position by alkyl, alkenyl, cycloalkenyl and alkoxy groups in many cases gives compounds whose potencies and selectivities are significantly greater than those of the parent compound.