Abstract: This invention relates to certain novel compounds and derivatives thereof, their synthesis, and their use as selective alpha-1a adrenergic receptor antagonists. One application of these compounds is in the treatment of benign prostatic hyperplasia. These compounds are selective in their ability to relax smooth muscle tissue enriched in the alpha 1a receptor subtype without at the same time inducing orthostatic hypotension. One such tissue is found surrounding the urethral fining. Therefore, one utility of the instant compounds is to provide acute relief to males suffering from benign prostatic hyperplasia, by permitting less hindered urine flow. Another utility of the instant compounds is provided by combination with a human 5-alpha reductase inhibitory compound, such that both acute and chronic relief from the effects of benign prostatic hyperplasia are achieved.

Abstract: Disclosed are spirocyclic compounds of the formula: ##STR1## The compounds of formula I are oxytocin antagonists useful in the treatment of preterm labor and dysmenorrhea, and for the stoppage of labor preporatory to Caesarian delivery. Also disclosed are pharmaceutical compositions containing these compounds as well as methods for preparing the compounds.