111516-03-1 15260-10-3 172846-16-1 54784-63-3 EINECS 239-304-5 L-Threonine, N-((1,1-dimethylethoxy)carbonyl)-O-(phenylmethyl)- N-((1,1-Dimethylethoxy)carbonyl)-O-(phenylmethyl)-L-threonine NSC 334365 O-Benzyl-N-tert-butoxycarbonyl-L-threonine