alloxazine benzo[g]pteridine-2,4-dione isoalloxazine chebi_ontology 214.18040 InChI=1S/C10H6N4O2/c15-9-7-8(13-10(16)14-9)12-6-4-2-1-3-5(6)11-7/h1-4H,(H2,12,13,14,15,16) Beilstein:991206 HAUGRYOERYOXHX-UHFFFAOYSA-N 0 O=c1nc2[nH]c3ccccc3nc2c(=O)[nH]1 CHEBI:37327 C10H6N4O2 benzo[g]pteridine-2,4(3H,10H)-dione 214.04908