Fig. 5.

The binding modes for SAHA and compounds 15a, 15c, 15g, 15j, and 15k at the active site of HDAC1, according to molecular docking calculations. The stacking interactions are shown as a pink line, hydrogen bonds are displayed as green dotted lines, π-alkyl interaction is displayed as middle pink, Van der Waals attraction is placed as green circles, interaction π-σ is displayed as purple lines, the coordination bond with zinc is shown as a purple circle. The observed distances of interaction between zinc and the closest oxygen of hydroxamic acid moiety of SAHA, 15a, 15c, 15g, 15j, and 15k are 3.9, 12.7, 5.8, 7.2, 5.0, and 14.4 Å, respectively