Trihydroxy-octadecadienoic acids

Strain ALA2 converted y-linolenic acid (18 3 all ds-6,9,12) to several products including 12,17 13,17-diepoxy-6,9-octadecadienoic acid 12,13,17-trihydroxy-6(Z),9(Z)-octadecadienoic acid and 12-hydroxy-13,16-epoxy-6(Z),9(Z)-octadecadienoic acid as depicted in the top half of Figure 16.2 (Hosokawa et al, 2003a). Strain ALA2 also converted the substrate arachidonic acid (20 4 all civ-5,8,11,13) to cyclic and trihydroxyl fatty acids as reported previously (Hosokawa et al., 2003a). These reactions resulted in compounds 14,19 15,19-diepoxy-5(Z),8(Z),ll(Z)-eicosatrienoic acid 14-hydroxy-15,18-epoxy-5(Z),... 

Kato, T., Yamaguchi, Y., Ohnuma, S. I., Uyehar, T., Nmai, T., Kodama, M., and Shibara, Y. 1986. Structure and synthesis of ll,12,13-trihydroxy-9Z,15Z-octadecadienoic acids from rice plant suffering from rice blast disease. Chem. Lett.,27,577-580. 

The ability of several oxygenated Cig fatty acids, such as 174 and 177, isolated from rice plants (including Fukuyuki) suffering from rice-blast disease, to act as self-defense substances against the fungus, has attractive synthetic interest. Zinc-mediated addition of propargyl bromide to (S,S)A61 provides (iS)-173, which is converted in nine steps to (11 S, 12 S, 135)-trihydroxy-(9Z,15Z)-octadecadienoic acid (174) [67]. 

Hamberg, M., Vanadium-Catalyzed Transformation of 13(5)-Hydroperoxy-9(Z), 11 ( )-Octadecadienoic Acid Structural Studies on Epoxy Alcohols and Trihydroxy Acids, Chem. Phys. Lipids 43 55-67 (1987). 

Kato, T., Y. Yamaguchi, S. Ohnmna, T. Uyehara, T. Namai, M. Kodama, and Y. Shiobara, Structure and Synthesis of ll,12,13-Trihydroxy-9(Z),15(Z)-octadecadienoic Acids from Rice Plant Suffering from Rice Blast Disease, Chem. Lett. 27 577-580 (1986). 

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