(E)-8-(3,4-Dihydroxystyryl)-7-methyl-1,3-dipropylxanthine 151539-46-7 1H-Purine-2,6-dione, 3,7-dihydro-8-(2-(3,4-dihydroxyphenyl)ethenyl)-1,3-dipropyl-7-methyl-, (E)-