SYNTHETIC APPROACHES TO NOVEL DI(FUROCOUMAROLE) ANALOGS AND SOME RELATED OXYGEN-CONTAINING FUSED-RING SYSTEMS OF ANTICIPATED ANTICOAGULANT ACTIVITY

Three derivatives of nyl-4-hydroxy-2H-furo[2,3-g]-[1]-benzopyran-2-one ) were prepared as dicoumarole analogues by condensation of enyl-4-hyd roxy-2H-furo[2,3-g]-[1]-benzopyran-2-one (II) with aliphatic and/or ar omatic aldehydes. Cyclization of these products with o-hydroxy aldehyd es or acetic anhydride afforded the related fused ring systems of two types. Synthesis of additional members of these oxygen-containing ring systems was effected either by oxidative coupling of compound II with catechol in the presence of potassium iodate, or by interaction with salicylidenacetone and acyclic or cyclic beta-keto esters, respectivel y. Chemical structure of these products was confirmed on the basis of spectral analyses.