(1S,4R)-4-(2-Amino-6-(cyclopropylamino)-7-oxido-9H-purin-9-yl)-2-cyclopentene-1-methanol

This compound is an N-oxide derivative of abacavir, used as a reference standard for impurity analysis in pharmaceutical quality control. It is structurally characterized by a purine ring system with a cyclopropylamino substituent and a cyclopentenylmethanol group.