Synthesis of meso‐tetra acid and ester functionalized calix[4]pyrroles

Novel meso‐tetracarboxylic acid and meso‐tetraester functionalized calix[4]pyrroles were synthesized by condensation of pyrrole with levulinic acid and ethyl pyruvate in sufficient yields. In addition, mixed condensation products can also be synthesized using this method. These new compounds may be useful as molecular receptors and polyfunctional starting materials for further derivatization.