Purine is a heterocyclic organic compound constituting a pyrimidine ring fused to an imidazole ring.Purine can undergo direct C-H functionalization in the presence of palladium catalyst to form various biologically important products.;Purine is a heterocyclic organic compound constituting a pyrimidine ring fused to an imidazole ring.Purine can undergo direct C-H functionalization in the presence of palladium catalyst to form various biologically important products.