The structure of N-carboxyphenylhydrazido-glycine (IV) is based on the following evidence:(1) Its infrared spectrum shows a single peak at 3247 cm.-l and an amide I1 absorption at 1553 cm.-I, characteristic of secondary amide^.^(2) Its ultraviolet spectrum has maxima at 2330 and 2820 k., characteristic of 2-acyl-1-phenylhydrazines. s (3) Its ethyl ester was cleaved by Raney nickel to give hydantoic acid ethyl ester (VI).