| Popis: |
The interactive profile between human serum albumin (HSA, the main carrier of endogenous and exogenous compounds in the human bloodstream) and five potential anticandidal agents, namely 2,3-dihydro-2-phenyl-naphtho[1,2-b]furan-4,5‑dione (1) and its derivatives 2–5 was studied by biophysical techniques, i.e., UV–vis, circular dichroism, steady-state and time-resolved fluorescence, combined with in silico calculations. The Stern-Volmer quenching constant (KSV) trend in three different temperatures and the bimolecular quenching rate constant (kq ≈ 1012 M−1s−1) values indicated a ground-state association HSA:1–5 which was confirmed by time-resolved fluorescence decays. Both KSV and modified Stern-Volmer binding constant (Ka) values are in the order of 104 M−1, indicating a moderate binding affinity, following the same reported trend for 1,4-naphthoquinones (the isomeric form of the naphthoquinones under study). There is only one main binding site for HSA:1–5, probably the subdomain IIA where the Trp-214 residue can be found. The association is driven both enthalpically and entropically, perturbing both the microenvironment around Trp-214 residue and weakly the α-helix content of albumin. Overall, the β-2,3-dihydrofuran naphthoquinones 1–5 showed favorable binding affinity to HSA to achieve their therapeutical potential and control of effective dosages. |
