. "Catalysis of the reaction: 4-amino-2-methyl-5-diphosphomethylpyrimidine + 4-methyl-5-(2-phosphoethyl)-thiazole + H(+) = diphosphate + thiamine phosphate." . . "thiamin-phosphate diphosphorylase activity" . "thiamine-phosphate diphosphorylase activity" . "2-methyl-4-amino-5-hydroxymethylpyrimidine-diphosphate:4-methyl-5-(2-phosphoethyl)thiazole 2-methyl-4-aminopyrimidine-5-methenyltransferase activity" . "thiamin-phosphate pyrophosphorylase activity" . "thiamine monophosphate pyrophosphorylase activity" . "thiamine phosphate pyrophosphorylase activity" . "thiamine-phosphate pyrophosphorylase activity" . "thiamine-phosphate synthase activity" . "TMP diphosphorylase activity" . "TMP pyrophosphorylase activity" . "TMP-PPase activity" . . .