AIDS-005472 AIDS005472 Penicillin deriv. [2R-[2.alpha.(R*),4.beta.(R)]]-5,5-Dimethyl-.alpha.-[(phenylacetyl)amino]-N-(phenylmethyl)-4-[[[1-(2-phenyl-1-(hydroxymethyl)propyl]amino]carbonyl]-2-thiazolidineacetamide