NEW BASE-ALTERED ADENOSINE ANALOGUES: SYNTHESIS AND AFFINITY AT ADENOSINE A(1) and A(2A) RECEPTORS

N(6)-Substituted adenosine analogues containing cyclic hydrazines or chiral hydroxy (ar)alkyl groups, designed to interact with the S2 and S3 receptor subregions, have been synthesized and their binding to the adenosine A(1) and A(2A) receptors have been investigated. Examples of both types of compounds were found to exhibit highly selective binding (K(i) in low nM range) to the rat A(1) receptor.