An efficient synthetic method for the synthesis of novel chiral analogous of cilazapril and CCKA antagonists

An efficient synthetic method for the synthesis of novel chiral cilazapril and analogous of CCKA_antagonists is desciribed. The reactions proceed via acidic deprotection of tert-butyl -9 (S)-phthalimido octahydro-6, 10-dioxo- -6H- pyridazo[1,2-a] [1,2] diazepine-1(S)-carboxylate, without isolation, which then coupled with 1-methyl-3-amino-1,3- dihydro-5-phenyl-(2H)-1,4-benzodiazepine-2- one and allylamine using diethyl phosphorocyanidate as a coupling reagent afforded novel peptidomimetics in excellent yield. This sequence of reactions provided a simple four-reaction sequence and efficient synthesis of novel peptidomimetics.