oxidoreductase activity, acting on CH or CH2 groups thymine dehydrogenase activity https://github.com/geneontology/go-ontology/issues/28070 Catalysis of the reaction: H2O + thymine + acceptor = 5-methyl-barbiturate + donor-H2. RHEA:13469 molecular_function MetaCyc:RXN-8646 GO:0052620