PURINE-SUBSTITUTED ADENOSINE DERIVATIVES WITH SMALL N-6-SUBSTITUENTS AS ADENOSINE RECEPTOR AGONISTS

Adenosine, 6-hydroxylaminopurineriboside (HAPR), N6-methyladenosine an d various derivatives of which the synthesis is described, were evalua ted as adenosine receptor ligands in radioligand binding studies to pr obe the relative importance for affinity of small N-6-substituents. Th e findings were incorporated in a recently developed three-dimensional model for the adenosine A, receptor, rationalising the more or less e qual contribution to affinity of such different substituents as -OH an d -CH3.