(4S)-3-acetyl-2-((R)-carboxy(3-(2-chlorophenyl)-5-methylisoxazole-4-carboxamido)methyl)-5,5-dimethylthiazolidine-4-carboxylic acid,(4S)-3-acetyl-2-((R)-carboxy(3-(2-chlorophenyl)-5-methylisoxazole-4-carboxamido)methyl)-5,5-dimethylthiazolidine-4-carboxylic acid,Cloxacillin Impurity