Synfacts 2009(6): 0597-0597  
DOI: 10.1055/s-0029-1216709
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Four-Component Ugi Approach to Benzodiazepines

Contributor(s): Victor Snieckus, Toni Rantanen
M. Sañudo, M. García-Valverde*, S. Marcaccini, J. J. Delgado, J. Rojo, T. Torroba*
Universidad de Burgos, Spain and Universitá di Firenze, Sesto Fiorentino, Italy
Further Information

Publication History

Publication Date:
25 May 2009 (online)

Significance

A synthesis of β-turn mimetic 5-oxobenzo[e][1,4]diazepine-3-carboxamides is initiated by an Ugi reaction between arylglyoxals, para-substituted benzylamines, cyclohexyl isocyanide, and 2-azidobenzoic acid. The Ugi products undergo a Ph3P-mediated Staudinger-aza-Wittig cyclization to afford the benzodiazepines. The Ugi reaction proceeds in mediocre to good yields and the cyclization in good to excellent yields. The substrate scope was well studied with regard to the arylglyoxals and benzylamines, but not with respect to the isocyanide and azido benzoic acid.