Stereoselective Synthesis, Spectral Characterization, Docking and Biological Screening of Coumarin Derivatives

The compounds being synthesized in present research are chiral in nature so for getting enantiopure compounds, stereoselective synthesis was carried out by organocatalysis. The importance of enantiopure compounds can not be overstated because the living systems are chiral in nature and response of enantiomers can be very different in living systems. The organocatalysed synthesis was accumplished using 4-hydroxycoumarin and variously substituted dibenzylideneacetones as reactants and the organocatalyst being used was 9-amino-9-deoxyepiquinine. The range of enantioselectivity achieved was 24-95%. The synthesized compounds were characterized by UV, IR, H-1 NMR, C-13 NMR, EIMS, UVCD, VCD and Chiral HPLC. The major focus of this research was to develop anticoagulant compounds and therefore the molecular docking studies were carried out with crystal structure of vitamin k epoxide reductase (3kp9) and then screened for in-vitro anticoagulant activity by using warfarin as positive control. Out of six synthesized compounds, four compounds (1,2,5,6) have shown greater binding affinity with 3kp9 than warfarin. In in-vitro anticoagulant studies, all compounds showed improved IC50 values than warfarin. Besides anticoagulant activity, antimocrobial activities were also carried out with six different strains of bacteria and fungi. Compound (5) showed 79% inhibition against Bacillus subtillis and 62 % inhibition against Staphylococcus aureus.