(2R)-2-(4-{N-[(1R)-2-Hydroxy-3-(2-phenylacetylamino)-1-benzylpropyl]carbamoyl}(4S)-5,5-dimethyl(1,3-thiazolidin-2-yl))-2-(2-phenylacetylamino)-N-benzylacetamide AIDS-005498 AIDS005498 Penicillin deriv.