Synthesis and structural studies of 16‐ferrocenemethyl‐estra‐1,3,5(10)‐triene‐3,17β‐diol and its interaction with human serum albumin by fluorescence spectroscopy and in silico docking approaches.

16‐Ferrocenylmethyl‐estra‐1,3,5(10)‐triene‐3,17β‐diol crystallizes in a triclinic unit cell and P1 space group. It contains four crystallographic independent molecules in the unit, representing four different conformers of the ferrocene–hormone conjugate. It provides evidence of a low rotational barrier around C19–C20 and the existence of alpha and beta conformers. The four conformers are interconnected by hydrogen bonds through hydroxyl groups of rings A and D. Density functional theory studies show the rotational barrier energy to be 4.96 Kcal/mol and the preferred conformer has a dihedral angle φ2 (defined as C16–C19–C20–C21) of 85.79°. This angle represents the conformer with the lowest steric strains. Docking studies between the subject compound and human serum albumin (HSA) showed that the most likely binding pocket of HSA is drug‐binding site 2. Quenching fluorescence spectroscopy was used to study HSA–ferrocene conjugate interaction and results showed that the complex formation was static and dominated by van der Waals and electrostatic/hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]