(E)-8-(4,5-Dimethoxy-2-nitrostyryl)-1,3-diethyl-7-methylxanthine 155271-55-9 1H-Purine-2,6-dione, 3,7-dihydro-1,3-diethyl-8-(2-(4,5-dimethoxy-2-nitrophenyl)ethenyl)-7-methyl-, (E)-