Journal
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
Volume 406, Issue 9-10, Pages 2377-2387Publisher
SPRINGER HEIDELBERG
DOI: 10.1007/s00216-014-7631-0
Keywords
Ovothiol; Acid-base chemistry; Microspeciation; Thiolate basicity; Oxidative stress; H-1 NMR-pHtitration; (NNMR)-N-15; Antioxidant capacity
Funding
- TAMOP [4.2.1.B-09/1/KMR]
- OTKAT [73804]
Ask authors/readers for more resources
Ovothiol A, a small biomolecule with highly potent antioxidant capacity, and three newly synthesized derivatives were studied by H-1 NMR, N-15 NMR, UV- pH titrations, and a customized evaluation method. The omni-interactive imidazole, amino, carboxylate, and thiolate moieties of ovothiol A are quantified in terms of 32 microscopic protonation constants, the relative concentrations of 16 microspecies, 6 pairwise interactivity parameters, and 8 protonation shifts. The highest and lowest imidazole basicities differ by a record-breaking five orders of magnitude, and the predominant thiolate protonation constant is by far the smallest known thiolate logK value. The latter provides an indication as to why ovothiol A occurs naturally under deep-water circumstances only. Since thiolate basicities are in correlation with thiol-disulfide redox potentials, the eight different, fine-tunable thiolate basicities offer versatile and highly specific antioxidant capacities within one single molecular skeleton. This work is the first complete microspeciation of a tetrabasic, nonsymmetrical natural compound.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available