Singlet oxygen and natural substrates: functional polyunsaturated models for the photooxidative degradation of carotenoids

Autor: Margarethe Kleczka, Axel G. Griesbeck, Moritz Vollmer, Angelika Eske, Sarah Sillner, Alan de Kiff
Rok vydání: 2015
Předmět:
Zdroj: Pure and Applied Chemistry. 87:639-647
ISSN: 1365-3075
0033-4545
DOI: 10.1515/pac-2015-0209
Popis: The primary chemical reactions of singlet molecular oxygen with polyunsaturated carotenoids are the focus of this research report. Model compounds that exhibit electronic properties and substituent pattern similar to natural carotenes, xanthophylls or apocarotenoids, respectively, were investigated with regard to photooxygenation reactivity. For dienes and trienes as substrates, high tandem reactivity was observed and hydroperoxy-endoperoxides were isolated as the secondary products of singlet oxygen reaction. The electronic gem-effect on the regioselectivity of the ene reaction is conserved also in vinylogous positions and thus appears to originate from a radical-stabilizing effect. In an attempt to combine different peroxide groups derived from natural products as a tool for new pharmaceutically active products, a dyade synthesis of an artemisinine-safranol with subsequent singlet oxygen addition was realized.
Databáze: OpenAIRE