2-Thiazolidineacetamide, N-[2-(dimethylamino)ethyl]-4-[[[2-[[[(2R,4S)-5,5-dimethyl-2-[(1R)-2-oxo-1-[(phenylacetyl)amino]-2-[(phenylmethyl)amino]ethyl]-4-thiazolidinyl]carbonyl]amino]ethyl]amino]carbonyl]-5,5-dimethyl-.alpha.-[(phenylacetyl)amino]-, (.alpha.R,2R,4S)- AIDS-029858 AIDS029858 Penicillin G, ET(NH)2 deriv.