英文别名4-[(2-ethoxybenzoyl)amino]-2-methyl-5-propylpyrazole-3-carboxamide; Sildenafil Carboxamide Impurity; 4-[(2-Ethoxybenzoyl)amino]-1-Methyl-3-propyl-1H-pyrazole-5-carboxamide; Sildenafil Di-Amide Impurity; Sildenafil Impurity 28; 1H-Pyrazole-5-carboxamide, 4-[(2-ethoxybenzoyl)amino]-1-methyl-3-propyl-