ID 2.4.2.20 DE dioxotetrahydropyrimidine phosphoribosyltransferase. AN dioxotetrahydropyrimidine-ribonucleotide diphosphorylase. AN dioxotetrahydropyrimidine-ribonucleotide pyrophosphorylase. CA 5,6-dihydrouridine 5'-monophosphate + diphosphate = 5,6-dihydrouracil + CA 5-phospho-alpha-D-ribose 1-diphosphate. CC -!- Acts, in the reverse direction, on uracil and other pyrimidines and CC pteridines containing a 2,4-diketo structure. //