第 10 章 夏季北極海の海氷域減少がもたらす冬季ユーラシア …133 10.1 はじめに 近年の冬季，欧州から極東にかけてのユーラシ ア大陸の中高緯度帯はしばしば強い寒気に見舞わ
Total Synthesis of Taxol - 東京大学
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Total Synthesis of Taxol 2020. 10. 31. Yusuke Imamura
Transcript of Total Synthesis of Taxol - 東京大学
Total Synthesis of Taxol
2020. 10. 31.
Yusuke Imamura
Contents
2
1. Introduction
2. Construction of core structure
3. Reactivity of functionalities
Taxol
3https://proteopedia.org/wiki/index.php/Molecular_Playground/Taxol
Contents
4
1. Introduction
2. Construction of core structure
- B-ring construction
- D-ring construction
- Tail part introduction
3. Reactivity of functionalities
B-ring Construction
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Nakada’s B-ring Construction
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D-ring Oxetane Construction
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D-ring Oxetane Construction
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Reverse D-ring Construction
91. R. C. A. Isaacs, M. J. Di Grandi, S. J. Danishefsky, J. Org. Chem. 1993, 58, 3938.
Oxetane Opening
101. Farina, V.; Huang, S. Tetrahedron Lett. 1992, 33, 3929. 2. Nicolaou, K. C.; Nantermet, P. G.; Ueno, H.; Guy, R.
K.; Couladouros, E. A.; Sorensen, E. J. J. Am. Chem. Soc. 1995, 117, 624.
Introduction of Tail Part
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C7-OH Protection
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Professor 2nd last Last comment
Nicolaou Bn(H2, Pd(OH)/C)
TES(HF・py.)
Chemoselectivity vs olefin?
Danishefsky TBS(TBAF)
TES(HF・py.)
Too robust?
Wender Troc(PhLi)
TES(HF・py.)
Accidental?
Kuwajima TES(HF・py.)
Troc(Zn, AcOH)
Orthogonality to C13-OTBS
Mukaiyama TES(HF・py.)
TES(TFA)
Deprotected with C13-OTES
Takahashi BOM(H2, Pd/C)
TES(HF・py.)
For Danishefsky intermediate
Chida Bz(K2CO3, MeOH)
TES(HF・py.)
Chemoselectivity vs Ac?For Danishefsky intermediate
Nakada Bn(H2, Pd(OH)/C)
TES(HF・py.)
For Nicolaou intermediate
Contents
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1. Introduction
2. Construction of core structure
3. Reactivity of functionalities
C1 skeletal rearrangement
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C2 reduction
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Difficulty in C2 reduction
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C2 benzoylation
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C3 epimerization
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C4-20 carbon extension
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C4-20 Wittig reaction
201. Holton, R. A.; Juo, R. R.; Kim, H. B.; Williams, A. D.; Harusawa, S.; Lowenthal, R. E.; Yogai, S. J. Am. Chem.
Soc. 1988, 110, 6558. 2. Hara, R.; Furukawa, T.; Horiguchi, Y.; Kuwajima, I. J. Am. Chem. Soc. 1996, 118, 9186.
C7 oxygen introduction
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C7 epimerization
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C9,10 acetoxy ketone
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C9,10 acetoxy ketone
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C13 reduction
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C13 reduction
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Summary
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