Structure-reactivity relations for thiol-disulfide interchange
作者:Janette Houk、George M. Whitesides
DOI:10.1021/ja00256a040
日期:1987.10
di- and trithiols and the disulfides derived from either 2-mercaptoethanol or dithiothreitol. Reactions were conducted in methanol-d,/aqueous buffer (pH 7) or methanold, at 25 "C, using NMR spectroscopy to follow the reactions. These data were used to rank the dithiols in terms of reduction potential and to infer the structure of the disulfides formed from them on oxidation. There is a general correlation
Photo-reaction of lipoic acid and related organic disulphides: reductive acylation with aldehydes
作者:Makoto Takagi、Setsuo Goto、Tsutomu Matsuda
DOI:10.1039/c39760000092
日期:——
Irradiation of organicdisulphides in aldehyde solvents resulted in reductive fission of the S–S linkage giving the corresponding thiol and an equimolar amount of the thiol acylate for linear disulphides and mono S-acylated dithiols for cyclic disulphides.
Two substituents on C-4 drastically reduce the tendency of 1,2-dithiolane to polymerize, whereas they do not significantly alter the reactivity of the remote disulfide; the dithiolanes 1a–e show high reactivity towards the carbon nucleophile EtMgBr as expected for the enzyme-bound lipoic acid.
S–S Bond cleavage of polymerization resistant 1,2-dithiolanes by acetylides: intrinsic reactivity of enzyme-bound lipoic acid toward stable, localized carbanions
The SâS bond of polymerization-resistant 1,2-dithiolanes 2 was cleaved cleanly by acetylides 4, giving the corresponding ring-opened products 5 in aprotic THF (quenched as silylsulfide 6) and their re-cyclized products 6,7-dihydro-1,4-dithiepins 3 in protic ButOH in excellent yields. The reactivity of 2 is discussed in relation to the reductive acylation of the enzyme-bound lipoic acid (Lip-E2).