Synthetic studies towards the 2-aminopyrimidine alkaloids variolins and meridianins from marine origin

A nine-step synthesis of 9-amino-4-methoxypyrido[3′,2′:4,5]pyrrolo[1,2-c]pyrimidine, a tricyclic ring system present in the marine alkaloids variolins is described. The natural marine products meridianins C–E have been synthetized for the first time starting from N-protected 3-acylindoles.