4-[[[3-[2-[[(1,1-Dimethylethyl)amino]carbonyl]-4-ethoxy-1-pyrrolidinyl]-2-hydroxypropyl]amino]carbonyl]-5,5-dimethyl-.alpha.-[(phenylacetyl)amino]-N-(phenylmethyl)-2-thiazolidineacetamide, [2R-[2. AIDS-006807 AIDS006807 Penicillin, 1Pyrrol-OHPrNH2 analog