Exploring spectroscopic insights into molecular recognition of potential anti-Alzheimer's drugs within the hydrophobic pockets of β-cycloamylose

Abstract Over the years, reports on quantitative analysis of complexation between anti-Alzheimer's drugs and β-cycloamylose (β-CA) are lacking. Hence, a new kind of investigation on host-guest complexation of two novel and potential anti-Alzheimer's drugs referred to as compounds 1 and 2 with β-CA has been studied for a range of temperatures (293, 298, 305 K) using spectroscopic techniques at physiological pH. The evaluated association constant (Ka) and thermodynamic parameters [Gibb's free energy (ΔG), enthalpy (ΔH) and entropy (ΔS)] for these relatively novel host-guest complexes accessed a clear indication for the development of inclusion complexes (ICs) between them. The validation of such novel ICs has been critically accounted from FTIR, 1H NMR, COSY and NOESY spectroscopy. These new set of ICs were found to have 1:1 stoichiometry via. Job's plot for both the inclusions (compound 1 + β-CA and compound 2 + β-CA) and association constant (Ka) advocates the highest stability for compound 2 + β-CA. Highlighting the biochemical approach of these novel ICs, they were individually incorporated within β-CA for studying their inhibitory effect on mitochondrial respiratory rate and their respective IC50 values were also calculated. The outcome of the present study conveys superiority of such ICs in enriching the anti-Alzheimer's drugs properties so they could have profound application in in vivo analysis.