Spiro-polymerization: polytocopherols as antioxidants
Abstract
Phenolic antioxidants, such as tocopherols (vitamin E), have manifold physiological functions as lipophilic radical scavengers, being used in a huge variety of medications, healthcare products, food additives, cosmetics, and polymer stabilizers. The present 3-year project deals with the development of novel phenolic "super-antioxidants" which contain many phenol (tocopherol) units per molecule, so that a hitherto unmatched antioxidative localization and efficiency can be achieved. These compounds will be synthesized according to a novel reaction sequence (spiro-polymerization / reduction); the products – long linear or cyclic alkanes with dozens or hundreds of regularly distributed phenol or vitamin E units attached (“polytocopherols”) – are a completely new compound class, which opens ample ground for basic research. Synthesis, chemistry, structure-property relationships and applications of these novel and versatile compound class will be investigated within the present project. The theoretical foundation of spiro-polymerization and the regioselectivity of spiro/pyrano-pairing will be studied by computations, which will moreover be correlated to experimental data. The super-antioxidative compounds will be comprehensively analytically characterized by a combination of methods involving liquid and solid-state nuclear magnetic resonance spectroscopy, mass spectrometry and multi-detector size exclusion chromatography. They will be tested, both in vitro and in biological model systems, in terms of their antioxidative efficiency and radical-scavenging capacity, as they are promising candidates, for instance, as physiologically compatible stabilizers for polymers in food packing, or as medicinal preparations for protection of cellular membranes against the attack of reactive oxygen species, especially against oxidative burst events with high radical output due to their high concentration of antioxidatively active phenolic groups. The super-antioxidants are furthermore starting materials for the preparation of polyradicals, which are not only theoretically interesting, but also as organic magnets in materials science or as high-power spin labels, i.e. tags for molecules to better follow biochemical processes. The polyradicals´ properties will be studied by radical-related spectroscopic techniques (EPR, ENDOR) and correlated with theoretical work. The project work will be carried out within the framework of national and international cooperation.
spiro-polymerization tocopherol vitamin E antioxidants organic synthesis
Publikationen
Endbericht FWF-Projekt P-19081
Autoren: Rosenau, T. Jahr: 2011
Forschungsbericht (extern. Auftraggeber)
Project staff
Thomas Rosenau
Univ.Prof. Dipl.-Chem. Dr.rer.nat. DDr.h.c. Thomas Rosenau
thomas.rosenau@boku.ac.at
Tel: +43 1 47654-77411, 77471
Project Leader
01.11.2006 - 31.10.2009