Levothyroxine Sodium EP Impurity J;L-3,3- Diiodothyronine;L-3,3- Diiodothyronine; (2S)-2-amino-3-[4-(4-hydroxy-3-iodophenoxy)-3-iodophenyl]propanoic acid;Alanine, 3-[4-(4-hydroxy-3-iodophenoxy)-3-iodophenyl]-, L- (8CI);(2S)-2-amino-3-[4-(4-hydroxy-3-iodophenoxy)-3-iodophenyl]propanoic acid,O-(4-Hydroxy-3-iodophenyl)-3-iodotyrosine,Impurity in commercial preparation of Levothyroxine.,Levothyroxine Impurity