Reaction catalyzed by xanthine dehydrogenase (1.17.1.4)
+
+
H2O
=
+
4-hydroxypyrazolo(3,4-d)pyrimidine
+
ferricyanide
+
H2O
=
4,6-dihydroxypyrazolo(3,4-d)pyrimidine
+
ferrocyanide
