TY - JOUR A1 - Purohit, Akash M A1 - Patel, Rishi I A1 - Bhatt, Vidhi A1 - Mosaffa, Elias A1 - Bhattacharya, Biswajit A1 - Manna, Arun K A1 - Iyer, Bragadish A1 - Emmerling, Franziska A1 - Banerjee, Atanu T1 - Solvent induced ligand transmuted substituted pyrazole housed copper complexes: Synthesis, characterization, DFT and anti-microbial performance N2 - Pyrazole-based ligand systems 3,5-dimethylpyrazole (L1) and 1-hydroxymethyl-3,5-dimethylpyrazole (L2OH) were synthesized and utilized to form copper complexes in various solvent environments. The ligand L2OH exhibits significant solvent-induced ligand transformation in polar protic solvent. The structural and electronic characteristics of the synthesized complexes were elucidated by X-ray single crystallography, Fourier Transform Infrared (FTIR) and electronic spectroscopy (UV-VIS). Whereas the ligand transformation has been evidenced from FTIR and Nuclear Magnetic Resonance (NMR) spectroscopic techniques. Furthermore, Density Functional Theory (DFT) highlights the pivotal role of solvent effects in modulating ligand transformations and complex formation, contributing to the rational design of metal-based bioactive compounds. Electronic transitions of the metal complexes have been analysed by time-dependent DFT (TD-DFT) calculations. The findings reinforce the significance of transition metal complexes in the development of antimicrobial agents and metallo-pharmaceuticals. The synthesized pyrazole compounds showed 100% inhibition against bacterial strains Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis and the yeast Candida albicans at a concentration ranging from 3.9 to 62.5 µg/ml depending upon the strain tested. KW - Pyrazole derivatives KW - Antibacterial and antifungal activity KW - Solvent induced ligand transformation Copper complexes KW - DFT study PY - 2025 DO - https://doi.org/10.1016/j.molstruc.2025.143001 SN - 0022-2860 VL - 1345 SP - 1 EP - 12 PB - Elsevier B.V. AN - OPUS4-63746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -