Total Synthesis and Biological Activity of 13,14-Dehydro-12-Oxo-Phytodienoic Acids (Deoxy-J1-Phytoprostanes)
✍ Scribed by Mazhar Iqbal; Paul Evans; Agustí Lledó; Xavier Verdaguer; Miquel A. Pericàs; Antoni Riera; Christiane Loeffler; Alok K. Sinha; Martin J. Mueller
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 149 KB
- Volume
- 6
- Category
- Article
- ISSN
- 1439-4227
No coin nor oath required. For personal study only.
✦ Synopsis
In plants, almost all abiotic and biotic stresses are associated with enhanced endogenous production of reactive oxygen species and free radicals. Free radicals in turn readily attack unsaturated fatty acids in membrane lipids that can be non-enzymatically oxidised to a variety of products in situ. Eventually oxidised lipids are released from membrane stores. It becomes increasingly clear that several of these oxidised lipids, such as malondialdehyde and the recently discovered phytoprostanes that occur ubiquitously in plants, can be induced by oxidative stress and display potent biological activities. [1,2] Consequently it has been postulated that oxidised lipids represent archetype mediators of oxidative stress, not only in plants but also in animals. [3] The major metabolites of the phytoprostane pathway are deoxy-J 1 -phytoprostanes (dPPJ 1 ), which structurally resemble potent, enzymatically formed defence mediators in plants and animals such as 12-oxo-phytodienoic acid (OPDA) and 15deoxy-D 12,14 -prostaglandin J 2 (dPGJ 2 ; Scheme 1). Notably, these cyclopentenone phytoprostanes are more abundant than OPDA even in young and unstressed plants. [4] However, it is not known whether the recently discovered dPPJ 1 s are merely markers of oxidative stress or are biologically active stress metabolites. It was the aim of this study to systematically prepare and evaluate these cyclopentenone phytoprostanes.
In 1976, Pryor and co-workers discovered that a-linolenic acid is prone to undergoing autoxidation to yield a series of prostaglandin-like compounds by a free-radical-catalysed lipidperoxidation process in vitro. [5] This finding remained a laboratory curiosity until 1990, when it was shown that arachidonic acid undergoes a similar radical-catalysed oxidation to yield [a] Dr.