A. Khalaj et al., A short and efficient synthesis of novel N-(2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl)-2-carboxamides, MONATS CHEM, 132(6), 2001, pp. 747-752
Several novel N-(2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl)-2-ca
rboxamides were prepared by acyl coupling of 2-aminobenzophenones with alph
a-(benzotriazol-1-yl)-N-acylglycines followed by displacement of the benzot
riazole ring with ammonia and cyclization of the resulting monoacyl aminals
. In addition to high yields and shorter reaction sequences due to avoiding
deprotection and acylation of the protected 3-amino-1,4-benzodiazepin-2-on
e intermediates, the present approach did not involve the use of toxic and
odoriferous materials as is the case with other methods.