The structure of fenoterol, a β2-adrenoceptor agonist used in therapy, has been joined with furoxan NO-donor moieties to give new NO-donor β2-agonists. The furazan analogues, devoid of the property to release NO, were also synthesized for comparison. All the compounds retained β2-agonistic activity at micromolar or submicromolar concentration when tested on guinea pig tracheal rings precontracted with carbachol. Among the ...