(-)-(S)-8-(3-Oxocyclopentyl)-1,3-dipropylxanthine 151581-23-6 1H-Purine-2,6-dione, 3,7-dihydro-8-(3-oxocyclopentyl)-1,3-dipropyl-, (S)- APAXIFYLLINE Apaxifylline [USAN:INN]