EFFECT ON FREE-RADICAL PROCESSES OF SOME ASCORBIC-ACID ANALOGS

Ascorbic acid, present in plasma from humans at concentrations of 50 t o 200 mu mol/l, has multiple antioxidant properties, Structural modifi cation of this vitamin by the introduction of lipophilic moieties has allowed to the development of ascorbate esters and ethers active as fr ee radical quenchers, Thus, a new series of ascorbic acid analogues po ssessing one or two aromatic rings was prepared in an attempt to synth esize potent antioxidants with lipophilic properties, Substituted 3-hy droxy furan-2 (SH)-ones and in some cases, dihydrofuro[3,4-b]pyrones w ere prepared, The synthesized compounds were evaluated for their antio xidant activity in vitro. So, -methoxybenzoyl)-3-hydroxy-5-phenylfuran -2(5H)-one 3e (IC50 = 3.06 x 10(-4) M) was found to be the most effect ive in scavenging the superoxide anion, whereas l-3-hydroxy-5-(3,4-dim ethoxyphenyl)furan-2(5H)-one 3d (IC50 = 1.38 x 10(-4) M) was the most active in inhibiting, lipid peroxidation.