Synthesis and biological evaluation of new benzo[f]furo[2,3‐h]‐and benzo[f]pyrano[2,3‐h]coumarin derivatives.

Abstract

Furocoumarins 3,5 and pyranocoumarin 7 were synthesized from the reaction of furonaphthalenediones 2,4 and pyranonaphthalenedione 6 respectively with carbethoxymethylene(triphenyl)phosphorane in refluxing DCM for 3‐6 hours or under microwave irradiation in toluene for a few minutes. Compounds 3,5,7 and their precursors were tested as anti‐inflammatory/antioxidant agents. They were found to compete significantly high DMSO for OH radicals, to scavenge O2− and to inhibit lipoxygenase to a high extent.

Natural and Synthetic Coumarins with Effects on Inflammation

“…All tested compounds [52], highly inhibited soybean lipoxygenase, competing with DMSO for OH • and some induced protection against carrageenan induced rat paw edema. Another series [53] showed similar results for competition with DMSO for OH • , for O 2 − scavenging and lipoxygenase inhibition. The biological results of synthetic coumarins are summarized in (Table 4).…”

“…A methodology to prepare coumarins from ortho-benzoquinones has been used for the synthesis of benzopyranocoumarins 39 [51,52,53] analogs to benzo[1]khellactone. All tested compounds [52], highly inhibited soybean lipoxygenase, competing with DMSO for OH • and some induced protection against carrageenan induced rat paw edema.…”

Synthesis and Biological Evaluation of Substituted Fused Dipyranoquinolinones

“…The formation of the pyran moiety of fused pyranocoumarins is achieved mainly by the Claisen rearrangement of propargyloxycoumarins followed by cyclization [37] or by the reaction of hydroxycoumarins with α,β-unsaturated aldehydes or ketones [38]. In this paper, we build on our extensive experience in the synthesis of fused pyridocoumarin [39][40][41][42][43][44][45][46] and pyranocoumarin derivatives [47][48][49][50][51][52], and recently published work on fused coumarins with pyridine and pyran moieties [39], and propose the synthesis and biological evaluation of substituted fused pyridopyranocoumarins. We are using new substituted fused pyridocoumarins, which, through the propargyloxy derivatives, are transformed to the title compounds via Au-nanoparticles catalysis.…”