Kinetics and mechanism of the oxidation of N-acetyl homocysteine thiolactone with aqueous iodine and iodate
作者： Ashley Sexton , Wilbes Mbiya , Moshood K. Morakinyo , Reuben H. Simoyi
DOI: 10.1021/JP408540U
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摘要: The kinetics of N-acetyl homocysteine thiolactone (NAHT) oxidation by aqueous iodine and iodate were studied spectrophotometric techniques. iodate–NAHT reaction is slow results in the formation sulfoxide as sole product (NAHTSO). stoichiometry was deduced as: IO3– + 3NAHT → I– 3NAHTSO (S1). In excess conditions, iodide produced S1 oxidized to give iodine: 5I– 6H+ 3I2 3H2O (S2). Thus conditions overall a linear combination S2 that eliminates iodide, 5S1 S2: 2IO3–+ 5NAHT+ 2H+ I2 5NAHTSO H2O. There 1:1 for NAHT – reaction: NAHT+ H2O NAHTSO +2I– (S3). All reactions, S1, S3 occur simultaneously since they are all comparable rate; complex dynamics observed. Iodide catalyzes but inhibits S3. both It has most profound effect on ove...
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