Synthesis and evaluation of the pharmacological activity of rigid analogues of sympathomimetic catecholamines derived from bicyclo[2.2.1]heptane.

endo-3-Amino-exo-2-(3,4-dihydroxyphenyl)-2-hydroxybicyclo[2.2.1]he ptane (4a) and its N-isopropyl derivative (4b) were synthesized and assayed for their adrenergic activity on various isolated preparations. Compounds 4a and 4b, tested up to a dose of 10(-4) M, did not reveal any activity, either stimulant or blocking, on the alpha- and beta-adrenoceptors. Possible rationalizations of the results obtained, however, are suggested.