8-(p-sulfophenyl)-theophylline

8-(p-sulfophenyl)-theophylline is a synthetic, highly water-soluble derivative of theophylline, which belongs to the methylxanthine family.[1][2][3] It acts as a competitive antagonist at adenosine receptors, with notable selectivity for the A2A adenosine receptor subtype (Ki ≈ 57 nM) over A1 (Ki ≈ 3.2 μM), and is essentially inactive at A2B and A3 subtypes at typical concentrations.[1] Its competitive antagonism occurs at the orthosteric binding site, causing functional blockade of adenosine-induced signaling, particularly pathways mediated by Gs and Gi proteins (modulating cAMP and PKA activity).[1] The presence of the p-sulfophenyl group confers strong hydrophilicity and poor blood-brain barrier penetration, meaning it acts predominantly peripherally when administered in vivo. The drug is primarily used as a research tool for investigating peripheral adenosine signaling, cardiovascular pharmacology, and adenosine receptor biology, rather than as a marketed pharmaceutical. It may also modulate phospholipase C-related pathways in relevant tissue models.[1][2]

Other names

8-(p-sulfophenyl)-theophylline8-(4-sulfophenyl)theophyllinePsp-theophylline8-Pspt80206-91-3