Computational Density Functional Theory and Kinetic-Thermodynamic Stable Crown-Chair Conformers of Hydroxyphenyl Calix[4]resorcinarene Macrocycles: Molecular Docking, Antioxidant, Antibacterial and Photophysical Applications.

This study presents a multi-faceted investigation into the structural, electronic, and therapeutic profiles of the crown and chair conformers of CPRA, 2HPRA, 3HPRA, and 4HPRA macrocycles. A dispersion corrected standard density functional theory (DFT/B3LYP-D3) calculations were utilized for geometric optimization, Mulliken atomic charge analysis, and to evaluate conformational stability based on relative energy values. Frontier Molecular Orbital (FMO) analysis, global reactivity descriptors, and dipole moments reveal that the crown conformers exhibit significantly elevated chemical reactivity compared to their chair counterparts. Thermodynamic assessments further delineate the reaction pathways, confirming the kinetic and thermodynamic stability of the products. These theoretical insights are corroborated by topological mapping include Molecular Electrostatic Potential (MESP), Electron Localization Function (ELF), and Localization of Electron Density (LOL) analyses which map the reactive sites, electron distribution, and intramolecular hydrogen bonding networks. Experimentally, the macrocycles were rapidly synthesized within 30-60 min, and their crown-chair conformations were confirmed via