Seminar

Seminar

[세미나공지] 2014년 11월6일(목)

  • POSTED DATE : 2014-11-04
  • WRITER : 관리자
  • HIT : 2974
  • DATE : 2014-11-06
  • PLACE : 세미나실 330226호
안녕하세요.


정규세미나는 11월 6일 4시부터 더블헤더로 두 건이 개최됩니다.          

많은 참석 부탁드립니다.
감사합니다. 

 

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정규세미나1.

 

제  목 : Chasing Phosphohistidine, “Dark Matter” in the Phosphoproteome

 

연  사 : 기정민 교수(UNIST)

 

일  시 : 2014년 11월 6일(목) 오후 4시


장  소 : 화학관 세미나실 (330226호실)

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Chasing Phosphohistidine, “Dark Matter” in the Phosphoproteome


Jung-Min Kee

Department of Chemistry, UNIST, 50 UNIST-gil, Ulsan 689-798, Korea


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My research program in chemical biology is aimed at driving innovations in biology and medicine by utilizing synthetic protein chemistry. I will discuss my recent work on phosphohistidine (pHis), an unstable protein post-translational modification (PTM). Although the importance of pHis in cell signaling and metabolism has been long recognized, the full scope and exact function of protein histidine phosphorylation is not clearly understood. It is mainly due to the chronic lack of adequate research tools to investigate the unstable PTM. We provided first glimpse at this “dark matter” in the phosphoproteome through the development of stable phosphohistidine (pHis) analogs and specific antibodies towards pHis-containing proteins. The antibodies enabled the first selective detection and isolation of pHis proteins from native cell lysates. The phosphoproteomic workflow for pHis was also developed by synergistic combination of immunoenrichment and bioinformatic tools, thereby opening new opportunities.


 

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정규세미나2.

 

제  목 : A Catalytic Enantioselective Glycolate Aldol Reaction via Lewis Base Activation of Lewis Acids and A General Enantioselective Approach to the Chemical Synthesis of the Chlorosulfolipids

 

연  사 : 정원진 교수(GIST)

 

일  시 : 2014년 11월 6일(목) 오후 5시


장  소 : 화학관 세미나실 (330226호실)

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A Catalytic Enantioselective Glycolate Aldol Reaction via Lewis Base Activation of Lewis Acids

and A General Enantioselective Approach to the Chemical Synthesis of the Chlorosulfolipids

 

Won-jin Chung

Department of Chemistry, GIST, Gwangju, Korea

 

Part 1. A general, efficient, Lewis-base catalyzed enantioselective addition of glycolate-derived silyl ketene acetals to a wide range of aldehydes will be presented. Both syn- and anti-diastereomers are accessible without changing the catalyst or controlling the geometry of the silyl ketene acetal. Simple modification of the size of alkyl groups on the silyl ketene acetal is sufficient to reverse the stereochemical course of the addition. The observed diastereoselectivity and reactivity could be rationalized by the analysis of six open transition state structures with the aid of computational analysis.

 

Part 2. A concise and general approach has been developed for the enantioselective synthesis of three structurally related chlorosulfolipids. Key advances include highly stereocontrolled additions to a,b-dichloroaldehydes, kinetic resolution of complex chlorinated vinyl epoxide intermediates, and Z-selective alkene cross metathesis of cis-vinyl epoxides. This strategy facilitated the synthesis of enantioenriched danicalipin A, mytilipin A, and malhamensilipin A in nine, eight, and eleven steps, respectively.

 

References

1. Chung, W.-j.; Carlson, J. S.; Vanderwal, C. D. J. Org. Chem. 2014, 79, 2226–2241.

2. Chung, W.-j.; Vanderwal, C. D. Acc. Chem. Res. 2014, 47, 718–728.

3. Chung, W.-j.; Carlson, J. S.; Bedke, D. K.; Vanderwal, C. D. Angew. Chem. Int. Ed. 2013, 52, 10052–10055.

4. Denmark, S. E.; Chung, W.-j. J. Org. Chem. 2008, 73, 4582–4595.

5. Denmark, S. E.; Chung, W.-j. Angew. Chem. Int. Ed. 2008, 47, 1890–1892.