A series of 1-(p-nitrophenyl)-2-aminoethanol derivatives and their morpholine analogues have been synthesized and pharmacologically investigated in order to confirm some pharmacological observations made with the N-isopropyl-substituted compounds. In agreement with the previously obtained results, the weak alpha-adrenergic-stimulating activity and the potentiating effect on the responses to norepinephrine found in the open-chain compounds persist in their corresponding semirigid cyclic analogues. The results are discussed in the light of common knowledge of the structure-activity relationships of alpha-adrenergic drugs.