2-Amino-1,3,4-thiadazole-5-sulfonamide; Tio-ura2-Amino-1,3,4-thiadazole-5-sulfonamide; Desacetyl acetazolamide; 5-Amino-1,3,4-thiadiazole-2-sulfonamide; Acetazolamide related compound D (USP); 5-Amino-1,3,4-thiadiazole-2-sulfonamide ; Acetazolamide EP Impurity D ;