| In vitro: | 
				| Bioorg Med Chem. 2011 Nov 1;19(21):6233-8.   |  | Effect of different C3-aryl substituents on the antioxidant activity of 4-hydroxycoumarin derivatives.[Pubmed:  21964183] |  The antioxidant activity of 4-Hydroxycoumarin synthetic derivatives and 4-methylumbelliferone were determined taking 4-Hydroxycoumarin as the reference compound.  METHODS AND RESULTS: Six 3-aryl-4-Hydroxycoumarin derivatives were synthesized from 4-Hydroxycoumarin as precursor in order to evaluate changes in their antioxidant properties due to C3-aryl substituent nature. Free radical scavenging capacities of these compounds against two different species DPPH(·) and ABTS(·+) and the protecting ability towards the β-carotene-linoleic acid co-oxidation enzymatically induced by lipoxygenase were measured. In addition, the relationship between the activities of these molecules against DPPH radical and the bond dissociation energy of O-H (BDE) calculated using methods of computational chemistry was evaluated. |  | Pharm Biol. 2011 Feb;49(2):190-3.  |  | Larvicidal activity of 4-hydroxycoumarin derivatives against Aedes aegypti.[Pubmed: 21043993] |  During our search for new types of coumarin derivatives possessing a larvicidal activity, we investigated the synthesis of 4-Hydroxycoumarin derivatives. METHODS AND RESULTS:  The structure analyses were conducted by nuclear magnetic resonance (NMR), and mass (MS) spectroscopy revealed that the coumarin derivatives were obtained in good yields, and the eight coumarin derivatives were 3-{1,2,3,4-tetrahydro-3-[4-(4-trifluoromethylbenzyloxy)phenyl}-1-naphthalen-1-on (1), 3-{1,2,3,4-tetrahydro-3-[4-(4-trifluoro methylbenzyloxy)phenyl}-1-naphthalen-1-ol (2), brodifacoum (3), difethialone (4), bromadiolone (5), 4-hydroxy-3-(1,2,3,4-tetrahydronaphthalen-1-yl)-2H-chromen-2-one (coumatetralyl) (6), cis-flocoumafen (7) and trans-flocoumafen (8). The compounds were tested against the F(21) laboratory strain of Aedes aegypti L. Brodifacoum and cis-flocoumafen mediated strong activity with an LC(50) values of 8.23 and 9.34 ppm, respectively.  CONCLUSIONS: The above indicates that brodifacoum may play a more important role in the toxicity of 4-Hydroxycoumarin derivatives. |  
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