(2R)-2-Phenyl-N-[(phenylmethoxy)carbonyl]glycyl-glycine 1,1-Dimethylethyl Ester is an intermediate used in the synthesis of Piperazinedione-carbonyl D-Phenylglycyl-glycine(P480165), which is an impurity of Piperacillin (P479950), a broad spectrum semi-synthetic antibiotic related to Penicillin.