Structural Studies by Exciton Coupled Circular Dichroism over a Large Distance: Porphyrin Derivatives of Steroids, Dimeric Steroids, and Brevetoxin B

详细信息    查看全文

• 作者：Stefan Matile ; Nina Berova ; Koji Nakanishi ; Jö ; rg Fleischhauer ; and Robert W. Woody
• 刊名：Journal of the American Chemical Society
• 出版年：1996
• 出版时间：June 5, 1996
• 年：1996
• 卷：118
• 期：22
• 页码：5198 - 5206
• 全文大小：272K
• 年卷期：v.118,no.22(June 5, 1996)
• ISSN：1520-5126

文摘

The present study (see ref 1) delineates the scope and limitationsof porphyrin chromophores for structuralstudies by the exciton coupled circular dichroic (CD) method. Adistance dependency of the porphyrin couplingwas investigated in the range between 10 and 50 Å. Over shortinterchromophoric distances, significant changes inthe conformational distribution introduced by the bulky porphyrinchromophores were observed. Over longer distances,the porphyrins showed ca. 10-fold sensitivity increase over commonlyused chromophores, and an effective directionfor the interacting porphyrin transition moments was assigned bycomparison. Porphyrins at the termini of dimericsteroids and brevetoxin B exhibited exciton coupling overinterchromophoric distances up to 50 Å. Theseresultsrepresent the porphyrins as promising reporter chromophores forextending the exciton coupled CD method to structuralstudies of biopolymers.