Xanthone and Flavone Derivatives as Dual Agents with Acetylcholinesterase Inhibition and Antioxidant Activity as Potential Anti-Alzheimer Agents

Figure 3

AChE active site (surface) bound to crystallographic donepezil (pdb ID: 4EY7) (a), galantamine (pdb ID: 4EY6) (c), and huperzine A (pdb ID: 4EY5) (e) (blue sticks). Residues involved in hydrogen interactions (yellow broken line), π stacking interactions (yellow double arrow), and π-cation interactions (orange double arrow) are displayed using a stick model. AChE carbon, oxygen, nitrogen, and hydrogen are represented in green, red, blue, and grey, respectively. 2D depiction view of crystallographic donepezil (b), galantamine (d), and huperzine A (f) in AChE active site. Hydrogen and π stacking are represented with the same color scheme. Receptor residues that are close to the ligand, but whose interactions with the ligand are weak or diffuse, such as collective hydrophobic or electrostatic interactions, are also represented (all the ones that have no indication for hydrogen-bonding). Solvent accessible surface area of the ligand is plotted directly onto the atoms in the form of a blue smudge. Solvent accessible surface area for the receptor residues is plotted as a blue halo.

(a)

(b)

(c)

(d)

(e)

(f)