Synthesis and biological assays of a series of 2-phenylpteridine derivatives are described to compare their affinities to adenosine receptors with those of the corresponding adenines, purposely prepared, and 8-azaadenines previously described. This study demonstrates that the enlargement of the five-membered ring of the adenine nucleus to a six-membered one is a modification that does not allow the molecules to maintain high activity towards adenosine receptors; in fact, pteridine derivatives did not show themselves to be good adenosine receptor ligands. On the contrary, N6-cycloalkyl- or N6-alkyl-2-phenyladenines showed a very high affinity and selectivity for A1 adenosine receptors. We demonstrate also that the 9-benzyl substituent is crucial for conferring high affinity for A3 receptors to molecules having a 2-phenyladenine-like nucleus.
|Autori:||GIORGI I; BIAGI G; LIVI O; LEONARDI M; SCARTONI V; PIETRA D|
|Titolo:||Synthesis of new 2-phenyladenines and 2-phenylpteridines and biological evaluation as adenosine receptor ligands|
|Anno del prodotto:||2007|
|Digital Object Identifier (DOI):||10.1002/ardp.200600168|
|Appare nelle tipologie:||1.1 Articolo in rivista|