Intramolecular energy transfer between chromophores separated by a rigid steroid bridge Ⅱ.Energy transfer as a probe to determine the ratio of two epimers  

作　　者：TONG Zhen-He YANG Guo-Qiang WU Shi-Kang Institute of Photographic Chemistry,Academia Sinica,Beijing 100012 

出　　处：《Chinese Journal of Chemistry》1990年第1期61-67,共3页中国化学（英文版）

摘　　要：The singlet-singlet intramolecular energy transfer between naphthalene moiety and dansyl group held apart by a rigid steroid bridge was investigated for two molecules:3β-(1-naphthyl)acetoxy- 17α-dansyl-△~5androstene(3a)and 3β-(1-naphthyl)acetoxy-17β-dansyl-△~5androstene(3b).The rates of energy transfer for 3a and 3b in cyclohexane are 6.9×10~6 and 1.1×10~8s^(-1) respectively.The difference in energy transfer rate between 3a and 3b is attributed to the different donor-acceptor separation and orientation.The ratio of the two epimers in the synthesized product mixture was obtained from the fluorescence decay measurements.The singlet-singlet intramolecular energy transfer between naphthalene moiety and dansyl group held apart by a rigid steroid bridge was investigated for two molecules:3β-(1-naphthyl)acetoxy- 17α-dansyl-△~5androstene(3a)and 3β-(1-naphthyl)acetoxy-17β-dansyl-△~5androstene(3b).The rates of energy transfer for 3a and 3b in cyclohexane are 6.9×10~6 and 1.1×10~8s^(-1) respectively.The difference in energy transfer rate between 3a and 3b is attributed to the different donor-acceptor separation and orientation.The ratio of the two epimers in the synthesized product mixture was obtained from the fluorescence decay measurements.

关 键 词：Energy transfer as a probe to determine the ratio of two epimers 

分 类 号：O6[理学—化学]