A Chemical Method for the Preparation of Novel 1,5‐Benzodiazepines Acting as CCK‐B Antagonists in High Enantiomeric Purity.

Abstract A series of new N-(1,5-benzodiazepin-3-yl)-N′-arylureas, 2 , bearing an alkyl substituent at the N5 position of the benzodiazepine nucleus has been studied as potential CCK-B antagonists. The homochiral compounds were obtained by resolving their precursors (amines 4 ) with a new resolution method based on the reaction between the amines and the chiral auxiliary 5 , the subsequent separation of the diastereomers ( 6 and 7 ) and the eventual removal of the auxiliary moiety by hydrogenation. The resolved amines and the corresponding final ureas showed good enantiomeric excesses.