87(P2-17) アメフラシより得られたホスホリパーゼA_2活性化作用を有する新奇不飽和脂肪酸代謝物の構造(ポスター発表の部)  [in Japanese] 87(P2-17) STRUCTURES OF NOVEL UNSATURATED FATTY ACID METABOLITES WITH PHOSPHOLIPASE A_2 ACTIVATING ACTIVITY FROM A SEA HARE APLYSIA KURODAI  [in Japanese]

The ethyl acetate extract of the sea hare Aplysia kurodai collected in Mie Prefecture was subjected to chromatographic separation, resulting in the isolation of a novel fatty acid metabolite (1) and the congeners [2, 3 (3a+3b)]. The major metabolite (1) was found to possess phospholipase A_2 activating activity. The planar structure of 1 was deduced by means of 2D NMR spectroscopy (^1H-^1H and ^<13>C-^1H COSY) and chemical derivatization. The octahydro derivative (6) of the metabolite (1), after acetylation, was cleaved by osmylation followed by periodate oxidation to afford two aldehydes (7, 8): the structure of 1 was unambiguously established by the detailed spectral analysis of 7 and 8. On the basis of the spectral data, the congener 2 was found to be the tetrahydro derivative of 1, while the congener 3 was shown to be a 1:1 mixture of 17, 18-dihydro-1 (3a) and 17',18'-dihydro-1 (3b).