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Determination of the absolute stereochemistry of vitamin E derived oxa‐spiro compounds by NMR spectroscopy

This contribution describes the structure elucidation of dimeric and trimeric oxidation products derived from natural (2R,4′R,8′R)‐α‐ and (2R,4′R,8′R)‐γ‐tocopherol, the most important lipid‐soluble vitamin E compounds and antioxidants in biological systems. Complete 1H and 13C NMR signal assignments have been obtained by combinations of one‐ and two‐dimensional NMR techniques. These structural investigations include full determination of stereochemistry and a study of dynamic processes. Copyright © 2001 John Wiley & Sons, Ltd.