Allopurinol Related CoMpound E;ethyl 5-(forMylaMino)-1H-pyrazole-4-carboxylate;Allopurinol Related Compound E (25 mg) (ethyl 5-(formylamino)-1H-pyrazole-4-carboxylate);ethyl 5-forMaMido-1H-pyrazole-4-carboxylate;Allopurinol Impurity 5(Allopurinol EP Impurity E)(Allopurinol USP Related Compound E );Allopurinol EP Impurity E(Allopurinol USP Related Compound E);Allopurinol EP Imp E;Allopurinol EP Impurity E or Allopurinol USP Related Compound E