全反式球形烯的光敏异构化及异构体的光谱

Photosensitized Isomerization of All - trans Spheroidene and Electronic Absorption Spectra of the Isomers

从Rhodobacter sphaeroides2.4.1提取了全反式球形烯,用高压液相色谱(HPLC)分离了它的I_2增感异构化产物:9,13’- cis(峰A),5,13- cis+13,9’-cis(峰B),13-cis(峰C),5,13’-cis(峰E_1),9—cis(峰E_2),13’-cis(峰F),5,9’-cis(峰G),9’-cis(峰H),all-trans(峰I),研究了异构体的结构对其电子吸收光谱及HPLC保留时间的影响,从而确认峰E_1为5,13’-cis.对全反式球形烯的光敏异构化机理也作了初步探讨.

All - trans - spheroidene was extracted from the cells of Rhodobacter sphaeroides 2. 4.1 and a set of cis - trans isomers [9,13' - cis(peak A) ,5,13 - cis + 13,9' - cis(peak B), 13- cis(peak C),5,13' - cis (peak E1), 9- cis (peak E2), 13' - cis (peak F),5,9' - cis(peak G),9' - cis(peak H),all- trans (peak. I)] were separated from an isomeric mixture obtained by iodine- sensitized photo - isomerization of the all - trans isomer by high - pressure liquid chromatography (HPLC)using a calcium hydroxide column. The effect of isomeric structures on electronic absorption spectra and retention of HPLC was studied and peak E1 was identified as 5, 13'- cis. The mechanism of photosensitized isomerization of all - trans spheroidene was also discussed.