Elucidating the sensing properties of thiophene amended organosilane for detection of chromium(III) ion and its potential activity against HIV-1 RT via computational approach

Abstract

This work describes the synthesis of thiophene based Schiff bases in which we incorporate the triazole allied organosilanes. This thiophene amended organosilanes showed good selectivity towards Cr 3+ ion. Further molecular docking study was done towards HIV-1 RT which showed the good binding energy between the protein and ligand(compound 4a). • Thiophene based organosilanes have been synthesized. • Absorption spectra were obtained to study the sensing property towards various metal ions. • Limit of detection, association constant and binding stoichiometry was calculated using linear calibration curve, B-H plot and job’s plot method respectively. • DFT calculations were carried out to optimize the geometry and generate FMO. • Molecular docking study was done with HIV-1 RT protein giving good binding energy. Thiophene modified organosilanes were synthesized by two manageable steps. Firstly, thiophene based Schiffbases (3a-3c) were synthesized by the simple condensation reaction further triazole allied organosilanes (4a-4c) were incorporated via Click chemistry and then characterized by various spectral techniques. The sensing property of synthesized compound 4a was studied using absorption studies. Among various metal ions compound 4a showed the recognisable behaviour towards trivalent form of chromium ion. The limit of detection and association constant were estimated to be 0.34 x 10 -7 M and 4.4 x 10 5 M -1 respectively.The selectivity of sensor 4a was unaltered in the presence of other metal ions. Job’s variation method was opted for calculating binding stoichiometry which showed 1:1 binding ratio. Binding mechanism was clarified by 1 HNMR spectroscopy. Further compound 4a and complex 4a-Cr 3+ were explored using density functional theory. Molecular docking study was carried out with HIV-1 RT and it showed the inhibitory activity towards reverse transcriptase by blocking the active site of enzyme. The lowest binding energy was found to be -6.91kcal/mol indicating effective association between ligand and protein. Hence compound 4a may act as a good potent inhibitor against HIV-1 reverse transcriptase enzyme.