Synthesis, Computational and Antimicrobial Study of 2-(2-Hydrazinyl)thiazole Derivatives

Abstract

In the present investigation, we report a combined computational and experimental study of eight thiazole derivatives (4a-4h) obtained from 3,4-dihydronaphthalen-1(2H)-one. A green chemistry protocol comprising PEG-400 and sulfamic acid was employed for the synthesis of eight diverse thiazole derivatives from 3,4-dihydronaphthalen-1(2H)-one, thiosemicarbazide and various phenacyl bromides. The synthetic strategy provides benefits like short reaction time, high yield, and non-chromatographic purification. The compounds were structurally confirmed on the basis of IR, 1HNMR and 13C NMR. The obtained thiazole derivatives were studied using the density functional theory (DFT) method employing B3LYP/6-311G(d,p) level of theory for optimization and Time-Dependent DFT (TD-DFT) approach for examining electronic energies and UV-Vis characteristics. Various computational parameters like bond length, bond angles, HOMO, LUMO, MESP, Mulliken charges, and global descriptors are obtained and discussed. The UV-Vis study the in gas phase and DMSO solvent was investigated to obtain various insights such as absorption energies oscillator strength, configurations and transitions of examined thiazole derivatives. The effect of polar solvent has augmented the absorption wavelength of all studied thiazole derivatives. The experimental and simulated UV-Vis data correlate with each other prompting the effectiveness of the computed method. The scaled and experimental wavenumbers provided the appropriate assignment of various vibrational signals. The antibacterial study was performed against E. coli, P. aeruginosa, and S. aureus which demonstrated the strong antibacterial potential against S. aureus. The antifungal study against C. albicans revealed that these compounds are poor antifungal agents. The DPPH and OH radical assays were used to establish the % radical scavenger effects and results showed that these derivatives are good antioxidant agents. The % hemolytic activity of the tested compounds showed that all compounds fall within the acceptable toxicity limit. Importantly in slico ADME and toxicity prediction studies of these compounds highlighted good ADME profile with no hepatotoxicity, immunotoxicity and cytotoxicity.