Synthesis and Experimental Structure of a Multifunctional Catechol‐Azomethinebenzoic Acid, DFT/DMol³ Calculations, and Molecular Docking with Hsp90

AbstractThe multifunctional catechol‐azomethine‐benzoic acid derivative 4‐[(E)‐[(2,3‐dihydroxyphenyl)methylidene]amino]benzoic acid (1) was prepared and the structure were confirmed by EI‐MS and 1H and 13C NMR spectroscopy. A Single‐crystal X‐ray diffraction study revealed coplanarity of the two aromatic rings within the imine function, supported by intramolecular N−H⋯O hydrogen bonds. In the crystal structure intermolecular O−H⋯O hydrogen bonds form chains, propagating along [010]. FT‐IR and Hirshfeld surface analysis confirms the multiple hydrogen bonding. DFT/DMol3 calculations localized the highest occupied molecular orbital (HOMO) on the o‐catechol unit, while the lowest unoccupied molecular orbital (LUMO) is delocalized over the entire molecule. The calculated map of electrostatic potential (MEP) showed relatively low values for both electrophilic and nucleophilic susceptibility. A molecular docking study of 1 in comparison with the established inhibitor geldanamycin (G) using the protein structure of the heat shock protein 90 co‐crystallized with G (Hsp90⋅G) showed that 1 occupies the same binding pocket as G in the Hsp90⋅G structure, indicating that the title structure might be a suitable inhibitor. The Swiss ADME approach showed promising general drug‐likeness properties for 1 with a relatively high lipophilicity (logP=1.68) and a logS value of −2.99 which lies in the middle of the logS distribution of traded drugs.