Project/Area Number |
26460028
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Chemical pharmacy
|
Research Institution | Tokushima Bunri University |
Principal Investigator |
|
Project Period (FY) |
2014-04-01 – 2017-03-31
|
Project Status |
Completed (Fiscal Year 2016)
|
Budget Amount *help |
¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
Fiscal Year 2016: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2014: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
|
Keywords | ascospiroketal / 1,4-addition reaction / asymmetric aldol / diastereo selective / ganmma-lactone / beta-lactone / decarboxylation / organic synthesis / asymmetric / synthesis / natural product / polyketide / 1,4-addition / aldol reaction / 結核 / 不斉1,4-付加 / 不斉アルドール / β-ラクトン / 連続不斉中心 / 不斉四級炭素 / 天然物合成 / ascospiroketals / tetraalkylated / all-carbon / quaternary center |
Outline of Final Research Achievements |
The synthesis of (+)-ascospiroketal B commenced from 2-propyn-1-ol, namely, Negishi iodomethylation of 2-propyn-1-ol followed by protection of hydroxy group by TBDPS and coupling reaction with (S)-2-phenyloxazolidinone accompanied insertion of CO catalyzed by Pd(PPh3)4 afforded 1. Then 1 was treated with vinyl copper reagent and converted to 2 in high diastereoselectivity. The aldol reaction of 2 accompanied by removal of oxazolidinone moiety to form b-lactone ring gave β-lactone 3 as a single isomer. Methylation of 3 with MeLi followed by ozonolysis and PDC oxidation produced γ-lactone 5 in good yields. Although Bayer-Viliger oxidation of 5 with usual reagent such as mCPBA did not proceeded due to the steric strain around methylketone.
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