Synthesis, characterization, DFT and molecular docking studies for novel 1,5-diphenylpenta-1,4-dien-3-one O-benzyl oximes

The main objectives of this study are: (a) to synthesize novel 1,5-diphenylpenta-1,4-dien-3-one O-benzyl oximes in an efficient way, (b) to investigate the synthesized molecules computationally via DFT calculations, (c) to compare computationally obtained data with experimental results and (d) to perform molecular docking calculations for the newly synthesized compounds and heat shock protein HSP90A N-terminal domain to determine the binding affinities of the investigated molecules and to reveal possible receptor-ligand interactions. In the first part of the study, syntheses and characterizations of the investigated compounds have been carried out. In this part, the target compounds have been synthesized and characterized successively. In the synthesis of target compounds from corresponding oximes, ultrasound has been used alternatively and results showed that the usage of ultrasound considerably increases the reaction rate and the efficiency. In the second part, detailed density functional theory calculations have been performed on the investigated compounds with the use of Becke, three-parameter, Lee-Yang-Parr hybrid functional and various basis sets. In this part, geometry optimizations, frequency analyses, NMR spectral analyses, frontier molecular orbital calculations, and molecular electrostatic potential map calculations have been performed. In NMR spectral analyses, both continuous set of gauge transformations (CSGT) and gauge-independent atomic orbital (GIAO) methods have been used and the obtained results with the use of various basis sets have been compared. Results showed that in NMR calculations, GIAO method is more successful than CSGT method and can provide satisfactory results even with small basis sets. In the third part of the study, molecular docking calculations have been performed on the investigated compounds and HSP90A N-terminal domain. Results showed that investigated molecules show a good binding affinity for HSP90A N-terminal domain. The binding affinities were found to be in the range of - 8.7 to - 10.1 kcal/mol.