The one-pot solution phase preparation of fused tetrazole-ketopiperazines

A novel application of the TMSN3 modified Ugi 4-component reaction is disclosed for the solution phase synthesis of fused tetrazole-ketopiperazine libraries. The reaction of an aldehyde, primary amine, methyl isocyanoacetate and trimethylsilylazide in methanol at reflux affords bicyclic tetrazole-ketopiperazines in good yield. This efficient one step protocol, producing products with three potential diversity points, may be used to generate arrays of biologically relevant small molecules for general and targeted screening.