Synthesis, in vivo Anticoagulant Evaluation and Molecular Docking Studies of Bicoumarins Obtained from Furocoumarin Peucedanin.

BACKGROUND: Synthesis of 7,7.-linked bicoumarins, 3,3.-linked bi(2-isopropyl)psoralens as well as 1H-1,2,3-triazole linked coumarin-2,3-dihydrofurocoumarin and furocoumarin-2,3-dihydrofurocoumarin hybrids was performed by two alternative pathways, either involving a catalyzed transformations of the ethynyl derivatives of plant coumarins - peucedanin or peuruthenicin. OBJECTIVE AND METHODS: The Sonogashira reaction of 7-ethynyl coumarins or 3-ethynyl-2-isopropylpsoralen with the subsequent coumarin triflates led to 7,7´-linked bicoumarins or 3,3´-linked bipsoralens. 1,2,3-Triazole linked coumarin-2,3-dihydrofurocoumarin or furocoumarin-2,3-dihydrofurocoumarin hybrids were synthesized by a regioselective Cu-catalyzed cycloaddition reaction of 2-azidooreoselone with 7-alkynylcoumarins or 3-ethynyl-2-isopropylpsoralen.
RESULTS: Pharmacological screening of synthesized bicoumarins for anticoagulant activity in vivo revealed that coumarin-dihydrofurocoumarin hybrids linked with a 1,2,3-triazole ring 20 and 22 were the most active compounds. The presented prothrombin time (PT) values comparable to the reference drug warfarin in a dose 100 mg/kg. Docking studies were undertaken to gain insight into the possible binding mode of these compounds with the coagulation factor Xa (FXa) binding site.
CONCLUSION: The moderate toxicity of compounds 20 and 22 (LD50 valuewas more than 3000 mg/kg) encouraged the further design of therapeutically relevant analogues based on these novel type of coumarin hybrids.