5-hydroxy-3,7-dihydropurine-2,6,8-trione 5-hydroxyuric acid 6960-30-1 NSC69826 5-Hydroxy-2,6-dioxo-2,5,6,7-tetrahydro-1H-purin-8-olate 5-Hydroxyisourate C11821 nchembio768-comp2