Virtual screening and QSAR study of some pyrrolidine derivatives as α-mannosidase inhibitors for binding feature analysis

Virtual screening and QSAR analysis were carried out to investigate the binding features of (2R, 3R, 4S)-2-aminomethylpyrrolidine 3,4-diol and the functionalized pyrrolidine derivatives to the α-mannosidase I and II enzymes. The QSAR models (possessed considerable R2, Q2 values, etc.) suggested that the presence of polar property on the vdW surface (vsurf_W, vsurf_Wp, etc.) of the molecules is important along with the presence of aromatic rings (opr_violation) in the molecules (which also provide hydrophobicity to the molecules). The docking study performed on α-mannosidase I and II enzymes pointed that the main interactions occur by hydrogen bonds, hydrophobic π–π stacking contacts and salt bridges with the cation calcium (for α-mannosidase I) and close interaction with zinc ion (α-mannosidase II), respectively. The bond flexibility orientates the aromatic ring in the molecules toward the hydrophobic cavity for π–π stacking contacts with the aromatic amino acids (Phe528, Phe329 and Phe659 for α-mannosidase I and Trp95, Tyr269, Phe312, Tyr102 for α-mannosidase II). The pharmacophore analysis also supports the results derived from the docking and QSAR studies. Our results suggest that the best compound to inhibit both classes of α-mannosidase is the compound 30, which may be used to design similar and better inhibitors to next generation drugs.

Virtual screening, QSAR and pharmacophore analysis of two set of compounds bearing the (2R, 3R, 4S)-2-aminomethylpyrrolidine 3,4-diol and the functionalized pyrrolidine derivatives with α-mannosidase inhibitory activity revealed that the bond flexibility along with number of aromatic groups are important for the hydrophobic π–π stacking interactions.Figure optionsDownload as PowerPoint slide