Dithioerythritol (DTE) is a sulfur containing sugar alcohol derived from the corresponding 4-carbon monosaccharide erythrose. It is an epimer of dithiothreitol (DTT). The molecular formula for DTE is C<sub>4</sub>H<sub>10</sub>O<sub>2</sub>S<sub>2</sub>.
DTE is a crystalline solid soluble in water and alcohols.
Like DTT, DTE makes an excellent reducing agent, which can be used for reduction of disulfide bonds. The reduction potential of DTE is the same as for DTT, about âÂÂ0.331 mV. The pK<sub>a</sub> values of the thiol groups of DTE are 9.0 and 9.9, which is higher than the corresponding values for DTT (9.3 and 9.5). Since reduction of disulfide bonds requires thiolate (ionized thiol), DTE is less efficient at lower pH compared to DTT.
Reduction with DTE is slower than with DTT. This is presumably because the orientation of the OH groups in its cyclic disulfide-bonded form (oxidized form) is less stable due to greater steric repulsion than their orientation in the disulfide-bonded form of DTT. In the disulfide-bonded form of DTT, these hydroxyl groups are trans to each other, whereas they are cis to each other in DTE.