The title compound, KW-3902 3.1.0(3,7)]nonyl)-3,7-dihydro-1H-purine-2,
6-dione, C20H28N4O2}, is a selective adenosine A1-receptor antagonist.
In the crystal of KW-3902, the mirror plane of the 3-noradamantyl gro
up is nearly in the plane of the xanthine moiety. The two propyl side
chains have fully extended conformations and are on the same side of t
he xanthine plane.