1986 Fiscal Year Final Research Report Summary
Chemical Studies on the Biologically Active Components of Tropical Plants and Animals
| Project/Area Number |
59430007
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| Research Category |
Grant-in-Aid for General Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Research Field |
天然物有機化学
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| Research Institution | Osaka City University |
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Principal Investigator |
HAYASHI Yuji Faculty of Science, Osaka City University, 理学部, 教授 (40046917)
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| Co-Investigator(Kenkyū-buntansha) |
NISHIZAWA Mugio Faculty of Science, Osaka City University ( - March, 1986) Faculty of Pharmacy,, 理学部, 助手 (40137188)
UEMURA Motokazu Faculty of Science, Osaka City University, 理学部, 講師 (90047241)
TOKUYAMA Takashi Faculty of Science, Osaka City University, 理学部, 助教授 (70046944)
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| Project Period (FY) |
1984 – 1986
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| Keywords | Lansium domesticum / Polycyclic Terpenoid Synthesis / Unsymmetrical Seco-onoceranoid Synthesis / Lansiolic Acid / <pi> (Arene) chromium Complexes / Stereospecific Carbon-Carbon Bond Forming Reaction / 中南米産蛙毒アルカロイド |
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| Research Abstract |
1. Lansiolic acid (1), the aglycone of an anti-allergic seco-onoceranoid glycoside Lansioside A isolated from fruit peels of Lansium domesticum (Meliaceae family), was synthesized by mean of a biomimetic cyclization of acyclic poly-olefin precursors. A decaline-type intermediate, prepared by the cyclization of farnesyl tolyl sulfone with mercury( <II> ) triflate/amine complex, was alkylated at C-11 with farnesyl bromide. Recyclization of this product under the same conditions at the newly-introduced farnesyl side chain led, via several minor steps, to an unsymmetrical onoceranoid <alpha> , <gamma> -onoceradienedione (2), a minor component of the fruit peels. This was the first total synthesis of a natural unsymmetrical onoceranoid. Simultaneous Beckmann fragmentation at both the carbonyl groups in the rings A and D of the compound 2 gave a bisseco-onoceranoid dicaboxylic acid, which was identified by the spectral manner with natural lansic acid, a major component of the fruit peels. Se
… More
lective reduction of the diketone 2 at the C-3 carbonyl group formed the corresponding carbinol, which was again cleaved at the D-ring ketone by the Beckmann fragmentation. The product was completely identical with the natural lansiolic acid.
2. Some fish-poisonous components were isolated from some Meliaceous species and characterized by the spectral bases.
3. By applying the particular chemical properties and characteristic stereo-chemistryof the arene ring in <pi> (arene)chromium tricarbonyl complexes, cis- and trans-hydroxycalamenenes, sesquiterpenoid fish-poisons from a Meliaceous plant, were synthesized stereoselectively. Analogous stereospecific C-C bond formations at benzylic, homobenzylic and bis-homobenzylic positions were also achieved via complexing chromium tricarbonyl group on the proper arene components.
4. Several neurotoxic bi- and tricyclic alkaloids were isolated from Dendrobates frog collected at tropical central and south America, and the structures were assigned by means of the two-dimensional NMR analysis. Less
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