Pyrrole derivatives have great importance in organic chemistry because they are present in many natural, medicinal and agricultural products, and semiconductor polymers. They are also very convenient precursors for biologically important compounds such as indolizidine alkaloids, bicyclic lactams, and unsaturated γ-lactams. 1, 1a, 1b, 1c, 1d, 1e and 1f There are various pyrrole syntheses in the literature. 2, 2a, 2b and 2c The most widely used method is the Paal–Knorr ...