Lopinavir EP Impurity F 

Chemical Name:  N-[(1S,2S,4S)-1-Benzyl-4-(formylamino)-2-hydroxy-5-phenylpentyl]-2-(2,6-dimethylphenoxy)acetamide (as per EP); 2-(2,6-Dimethylphenoxy)-N-[(2S,3S,5S)-5-formamido-3-hydroxy-1,6-diphenylhexan-2-yl]acetamide (as per USP)

Synonym: Lopinavir N-Formylphenoxyacetamide (USP)