A convenient method was developed for synthesizing 3-amino-1,5-benzodiazepine-2-one
derivatives via a Michael addition reaction of o-phenylenediamine with dehydroalanine HFI or HOBt ester derivatives (HFI = 1,1,1,3,3,3-hexafluoro-2-propyl;
HOBt = 1,2,3-benzotriazol-1-ol monohydrate), followed by cyclization. Interestingly,
the regio- and diastereoselectivities were confirmed by comparing the HFI and HOBt
esters. These simple methods were used to synthesize various N-substituted 3-amino-1,5-benzodiazepine-2-one derivatives in good yields.
Key words
1,5-benzodiazepines - Michael additions -
o-phenylenediamine - dehydroalanine - intramolecular cyclization