Synthesis of imidazolocoumarins by the amide-directed oxidative cyclisation of enol-Ugi derivatives
José Luis Ramiro1, Ana G Neo1, Carlos F Marcos1
1Laboratory of Bioorganic Chemistry & Membrane Biophysics (L.O.B.O.). Departamento de Química Orgánica e Inorgánica. Universidad de Extremadura, 10003 Cáceres, Spain. cfernan@unex.es.
Abstract:
The oxidative C(sp3)-H intramolecular imination of hydroxycoumarin enol-Ugi adduct derivatives affords selectively diversely substituted imidazolocoumarins in one pot. The amide group derived from the enol-Ugi isocyanide component directs the functionalisation of the adjacent C(sp3)-H and then is lost as an isocyanate molecule in an unprecedented transformation. This strategy was applied for the synthesis of potential modulators of innate immune system receptor TLR7, which showed high binding affinities in the molecular docking studies.
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