title: Analogues of 1,3-dipropyl-8-phenylxanthine: enhancement of selectivity at A1-adenosine receptors by aryl substituents.
abstract: The effect of a variety of aryl substituents on the potency and selectivity of 19 analogues of 1,3-dipropyl-8-phenylxanthine as antagonists at A1- and A2-adenosine receptors in brain tissue was determined. The 4-sulfamoylphenyl and 4-carbamoylphenyl analogues are potent and somewhat selective for the A1 receptor. None of the dihydroxyphenyl analogues are remarkably potent, but all are selective for the A1 receptor. 1,3-Dipropyl-8-(2-hydroxy-4-methoxyphenyl)xanthine is the most selective A1 antagonist of the analogues with a A1/A2 potency ratio of about 90.
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011983:Receptors, Purinergic; D013329:Structure-Activity Relationship; D014970:Xanthines / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D011956:Receptors, Cell Surface; D011983:Receptors, Purinergic; D014970:Xanthines; C049140:1,3-dipropyl-8-phenylxanthine