2,4-dihydroxypteridine + NH4(+) => 2-amino-4-hydroxypteridine + H2O + H(+)
2,4-dihydroxypteridine + nh4(+) => 2-amino-4-hydroxypteridine + h2o + h(+)
2,4-dihydroxypteridine + NH4(+) => 2-amino-4-hydroxypteridine + H2O + H(+)
2,4-dihydroxypteridine + nh4(+) => 2-amino-4-hydroxypteridine + h2o + h(+)