3(R)-{2-[(3S)-(tert-butyldimethylsilanyloxymethyl)-2-oxo-5-phenyl-2,3-dihydrobenzo[e][1,4]diazepin-1-yl]acetylamino}-4-samicarbazone-butyric acid tert-butyl ester

4-semicarbazone-3(S)-[2-(2-oxo-5-phenyl-3(R)-(phenylcarbamoyloxymethyl)-2,3-dihydro-benzo[e][1,4]diazepin-1-yl)acetylamino]butyric acid tert-butyl ester

4-semicarbazone-3(S)-[2-(2-oxo-5-phenyl-3(R)-(4-chlorophenylcarbamoyloxymethyl)-2,3-dihydro-benzo[e][1,4]diazepin-1-yl)acetylamino]butyric acid tert-butyl ester

4-semicarbazone-3(S)-[2-(2-oxo-5-phenyl-3(R)-(4-methoxyphenylcarbamoyloxymethyl)-2,3-dihydro-benzo[e][1,4]diazepin-1-yl)acetylamino]butyric acid tert-butyl ester

4-semicarbazone-3(S)-[2-(2-oxo-5-phenyl-3(R)-(2,4-difluorophenylcarbamoyloxymethyl)-2,3-dihydro-benzo[e][1,4]diazepin-1-yl)acetylamino]butyric acid tert-butyl ester