| Project/Area Number |
02640422
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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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 | Tokyo Institute of Technology |
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Principal Investigator |
FUJIMOTO Yoshinori Tokyo Institute of Technology, Department of Chemistry, Associate Professor, 理学部, 助教授 (50173472)
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| Project Period (FY) |
1990 – 1991
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| Project Status |
Completed (Fiscal Year 1991)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1991: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1990: ¥1,600,000 (Direct Cost: ¥1,600,000)
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| Keywords | ecdysteroid / 20-hydroxyecdysone / plant tissue culture / stable isotope / ^2H-NMR / biosynthetic pathway / 生合成機構 / 安定同位体標識化合物 / 毛状根 / Ajuga reptans / 生合成メカニズム |
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| Research Abstract |
1. Feeding experiment of (2- ^<13>C) acetate with the tissue culture of Ajuga hairy root revealed that it was incorporated into ecdysteroids efficiently. It was found that the 24-alkyl group of C-28 and C-29 ecdysteroids was not derived from acetate.
2. Feeding of synthetic (26, 27- ^<13>C_2) cholesterol as an emulsion into Tween80 to the tissue culture was allowed to incorporate into 20-hydroxy-ecdysone efficiently, but not into C-28 and C-29 ecdysteroids.
3. More importantly, the above experiment has demonstrated that stable isotopes such as ^1H and ^<13>C can be utilized in biosynthetic studies of ecdysteroids.
4. (3 - ^2H)- and (4 - ^2H) Cholesterols were chemically synthesized.
5. ^2H-NMR analysis of 20-hydroxyecdysones derived from the ^2H-labeled cholesterols revealed that the 3alpha- and 4beta-hydrogens were incorporated into 20-hydroxyecdysone without change of the location and stereochemistry.
6.5beta- ^2H derivative of an intermediate, 3beta-hydroxy-5beta-cholest-7-en-6-one, which was postulated by the aforementioned results, was synthesized and fed with the culture system. The feeding experiment demonstrated that the intermediate was metabolized into 20-hydroxyecdysone much better than cholesterol.
7. We now propose 3beta-hydroxy-5beta-cholest-7-en-6-one as a key intermediate in the earlier stage of ecdysone biosynthesis. Our present studies are focused on the identification of a precursor of this intermediate.
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