Work

Substituent-driven electronic structure, nonlinear optical response, and tubulin binding of anisole- and spiro-isatin-functionalized benzo[4,5-e]pyran derivatives: An integrated experimental and computational investigation

Year: 2026

Type: article

Abstract: To investigate the influence of donor- and acceptor-type substituent architectures on the properties of a common chromene framework, two structurally distinct benzo[4,5- e ]pyran derivatives, namely an anisole-functionalized chromene (1) and a spiro-isatin-functionalized chromene (2), were synthesized through a one-pot multicomponent reaction in aqueous medium under ambient conditions. Single-crystal X-ray diffraction analysis revealed that 1 crystallizes in the monoclinic C2/c space group, whereas 2 adopts the monoclinic P2₁/n space group, with both structures stabilized by hydrogen-bonding networks and supramolecular interactions. Density functional theory calculations at the B3LYP/6–311 G(d,p) level reproduced the experimental geometries and provided insight into the electronic and optical properties of the compounds. The calculated HOMO–LUMO energy gaps were 5.0020 eV for 1 and 5.0850 eV for 2. Time-dependent density functional theory calculations reproduced the observed UV–Vis absorption behavior, while the first hyperpolarizability increased from 8.63 × 10⁻³⁰ esu for 1–10.95 × 10⁻³⁰ esu for 2, corresponding to an approximately 27% enhancement in nonlinear optical response. Hirshfeld surface analysis identified H···H, H···C/C···H, and H···O/O···H contacts as the dominant intermolecular interactions. Molecular docking studies against the β-tubulin crolibulin-binding site and in silico ADME analysis indicated favorable molecular recognition and drug-likeness characteristics, particularly for compound 2. These findings establish clear substituent-dependent structure–property relationships and demonstrate the beneficial influence of the spiro-isatin framework on nonlinear optical response and predicted β-tubulin recognition.

Source: Next Materials

DOI: 10.1016/j.nxmate.2026.103699