1,4-Benzodiazepine N-nitrosoamidines: useful intermediates in the synthesis of tricyclic benzodiazepines.
1,4-Benzodiazepine N-nitrosoamidines have been used as scaffolds for the preparation of different tricyclic derivatives. Replacement of the N-nitrosoamidine moiety through treatment with the nucleophiles acetylhydrazine, aminoacetaldehyde dimethylacetal and 1-amino-2-propanol, followed by an acid-catalyzed cyclization step, afforded triazolo and imidazobenzodiazepines 1, 6, and 7, respectively, in good yields. When acetylhydrazine is used as a nucleophile, the overall process provides an alternative route to alprazolam (1b) and triazolam (1c), respectively.
Fustero
Santos
S
Departamento de Química Orgánica, Universidad de Valencia, 46100-Burjassot, Valencia, Spain. santos.fustero@uv.es
González
Javier
J
del Pozo
Carlos
C
D000578:Amidines / Q000737:chemistry*; D001569:Benzodiazepines / Q000737:chemistry*; D003500:Cyclization; D009574:Nitro Compounds / Q000737:chemistry*
D000578:Amidines; D009574:Nitro Compounds; D001569:Benzodiazepines