Synthesis, optical properties, structural aspects, and bioactivity of novel bis(thienylpyrazolyl)carbohydrazide...

The study investigates the synthesis, structure, optical features, and bioactivity of a new bis(thienylpyrazolyl)carbohydrazide derivative (compound 3). The compound 3 was prepared, in 90 % yield, via condensation of 1-phenyl-5-(thiophen-2-yl)-1H-pyrazole-3-carbohydrazide 1 with 1-phenyl-3-(thiophen-2-yl)-1H-pyrazole-4-carbaldehyde 2. X-ray crystallography analysis indicated a monoclinic crystal structure stabilized by hydrogen bonding and noncovalent interactions. Density functional theory (DFT) correlated effectively with experimental results, revealing unique molecular electrostatic potential (MEP) results. Experimental and DFT investigations indicated a large energy gap (5.18 eV; DFT: 4.08 eV), highlighting its stability and potential for light-sensitive applications. Optical investigations demonstrated a wavelength-dependent reflectance and adjustable dielectric characteristics, indicating stability and advantageous in optoelectronic and biological applications. Bioactivity revealed significant antibiofilm activity with up to 97.1 % inhibition at elevated doses. It exhibited selective cytotoxicity, with an IC₅₀ of 331.81 μg/mL against normal Wi38 cells, and 147.57 μg/mL for Caco2 cancer cells, indicating potential for treatment with fewer side effects. These results establish it as a viable medical agent for combating infections, and cancer, especially in immunocompromised patients. Molecular docking revealed a strong binding affinity toward the epidermal growth factor receptor (EGFR), with a docking score of -9.8 kcal mol^-1, confirming stable ligand-receptor interactions support its observed anticancer.