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|Section2= |Section3= }} Dithiothreitol (DTT) is the common name for a small-molecule redox reagent also known as Cleland's reagent. DTT's formula is C4H10O2S2 and the chemical structure of one of its enantiomers in its reduced form is shown at the right; its oxidized form is a disulfide bonded 6-membered ring (shown below). The reagent is commonly used in its racemic form, as both enantiomers are reactive. Its name derives from the four-carbon sugar, threose. DTT has an epimeric ('sister') compound, dithioerythritol (DTE). ==Reducing agent== DTT is a reducing agent; once oxidized, it forms a stable six-membered ring with an internal disulfide bond. It has a redox potential of -0.33 V at pH 7.〔 The reduction of a typical disulfide bond proceeds by two sequential thiol-disulfide exchange reactions and is illustrated below. The reduction usually does not stop at the mixed-disulfide species because the second thiol of DTT has a high propensity to close the ring, forming oxidized DTT and leaving behind a reduced disulfide bond. The reducing power of DTT is limited to pH values above 7, since only the negatively charged thiolate form -S− is reactive (the protonated thiol form -SH is not); the pKa of the thiol groups is 9.2 and 10.1. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dithiothreitol」の詳細全文を読む スポンサード リンク
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