The present invention provides compounds of the formula wherein R.sup.1,
R.sup.2, R.sup.3 and n have meaning as described in the specification, as
adenosine A.sub.2B receptor agonists and, thus, may be employed for the
treatment of diseases in mammals that are mediated by the A.sub.2B
receptor including, but not limited to, septic shock, cystic fibrosis,
impotence, diarrhea, and cardiac diseases Cardiac diseases include
hyperplasia consequent to hypertension, arteriosclerosis, and heart
attack