Synthesis, structure and biological evaluation of highly functionalized 2-azetidinone integrated spirooxindolopyrrolidine heterocyclic hybrid

Abstract Synthesis of structurally diverse novel class of azetidinone integrated spirooxindolopyrrolidine heterocyclic hybrid was achieved in excellent yield employing a single-pot intermolecular 1,3-dipolar cycloaddition cascade protocol. The highly functionalized dipolarophile, azetidinone Baylis-Hillman adduct, was prepared from 4-formyl azetidinone whereas the non-stabilized 1,3-dipole component was derived from trifluoromethoxyisatin and l -phenylalanine via decarboxylative condensation. The structure of the product was determined by X-ray diffraction on single crystal method. Further, the crystal structure was analyzed using Hirshfeld calculations. The packing of molecules is controlled by the O…H (19.2%), F…H (17.3%), C…C (3.2%) and N…H (14.8%) which are the most significant in cycloadduct. The electronic and reactivity descriptors of the cycloadduct were calculated on the basis of DFT calculations. The synthesized heterocyclic hybrid displayed significant activity against selected ESBL producing E. coli strains and the minimal MIC values was observed against E. coli WTP005.