Okada Youji, Tanaka Kaoru, Sato Eisuke, Okajima Haruo
Department of Analytical Chemistry, Faculty of Health Sciences, Kyorin University, 476 Miyasita-cho, Hachioji, Tokyo 192-8508, Japan.
Org Biomol Chem. 2008 Mar 21;6(6):1097-102. doi: 10.1039/b715727d. Epub 2008 Feb 18.
The antioxidant effects of the new thiosulfinate derivative, S-benzyl phenylmethanethiosulfinate (BPT), against the oxidation of cumene and methyl linoleate (ML) in chlorobenzene were studied in detail using HPLC. The results showed that BPT provided effective inhibition with a well-defined induction period under these oxidation conditions, and it was found that the stoichiometric factor (n), the number of peroxyl radicals trapped by one antioxidant molecule, of BPT is about 2. We then undertook a thorough investigation aimed at elucidating the active structural site of BPT. Various model compounds, such as diphenyl disulfide, dibenzyl disulfide, S-phenyl benzenethiosulfinate and S-ethyl phenylmethanethiosulfinate, were used which provided evidence that the benzylic hydrogen of BPT is mainly associated with the peroxyl radical scavenging. Moreover, we measured the rate constant for the reaction of BPT with peroxyl radicals derived from cumene and ML in chlorobenzene, and based on these measurements, BPT reacts with these peroxyl radicals with a rate constant of k(inh) = 8.6 x 10(3) and 6.2 x 10(4) M(-1) s(-1), respectively.
利用高效液相色谱法（HPLC）详细研究了新型硫代亚磺酸盐衍生物S-苄基苯甲硫代亚磺酸盐（BPT）对氯苯中异丙苯和亚油酸甲酯（ML）氧化的抗氧化作用。结果表明，在这些氧化条件下，BPT能有效抑制氧化反应，并具有明确的诱导期，且发现BPT的化学计量因子（n），即一个抗氧化剂分子捕获的过氧自由基数量约为2。然后，我们进行了深入研究，旨在阐明BPT的活性结构位点。使用了各种模型化合物，如二苯基二硫化物、二苄基二硫化物、S-苯基苯硫代亚磺酸盐和S-乙基苯甲硫代亚磺酸盐，这些化合物提供了证据，表明BPT的苄基氢主要与过氧自由基清除有关。此外，我们测量了BPT与氯苯中异丙苯和ML产生的过氧自由基反应的速率常数，基于这些测量结果，BPT与这些过氧自由基反应的速率常数分别为k(inh) = 8.6 x 10(3) 和6.2 x 10(4) M(-1) s(-1)。
