SYNTHESIS AND ANTIAGGREGATOR ACTIVITY OF SOME NEW DERIVATIVES OF 4H-1-BENZOPYRAN-4-ONE

A series of 2-[2-alkyl-1H-benzimidazol-5(6)-yl]-4H-1 analogues 7a-7e w as synthesized by the reaction with 3',4'-diaminoflavone and aliphatic carboxylic acids. 3',4'-Diaminoflavone 6 was prepared via the reducti on of 2-(4-amino-3-nitrophenyl)-4H-1-benzopyran-4-one 5a. The compound s 7a-e and 14a-f were tested in vitro for their inhibitory activities against human platelet aggregation induced by collagen, ADP and A23187 . The compound with a COOR group as a side chain, ihydro-1,4-benzodiox in-6-yl)-4H-1-benzopyran-4-one 14a-f, has potent activity, and so comp ound 13 was also prepared as an analogue of series 14 and tested for i ts antiaggregator activity.