Antioxidant and neutrophil-inhibiting properties of new 2-O-methyl-6-(alkylthio)ascorbic acid derivatives

A series of new 6-(alkylthio)ascorbic acids was synthesized, and their inhibitory effects on lipid peroxidation and the oxidative burst of human neutrophils were tested. Of 12 structurally different lipophilic ascorbic acid derivatives 6-S-n-hexadecyl-2-O-methyl-6-deoxy-6-thio-L-ascorbic acid (7b; B-003) inhibited the Fe 2+ /ADP-induced lipid peroxidation of rat liver microsomes with an IC 50 value of 2 pM. In human neutrophils, 7b most potently inhibited the fMLP-induced oxidative burst in a cell density-dependent manner with an IC 50 value of 0.6 μM at 5×10 5 cells/mL