ChemInform Abstract: Synthesis and Biological Data of 4-Amino-1-(2-chloro-2-phenylethyl)-1H-pyrazolo [3,4-b]pyridine-5-carboxylic Acid Ethyl Esters, a New Series of A1-Adenosine Receptor (A1AR) Ligands

The synthesis of a new family of A1-adenosine receptor (A1AR) ligands 3a–n has been performed in a straightforward way. Affinity data at A1AR, A2AAR and A3AR in bovine membranes show that these new compounds bind the A1AR in a selective way over A2AAR and A3AR and one of them (3j) presents a very high affinity, probably due to the phenethylamine substituent at C-4.