40040-82-2Relevant academic research and scientific papers
Influence of electron-donating and electron-withdrawing substituents on the Chemiluminescence behavior of Coelenterazine analogs
Saito, Ryota,Hirano, Takashi,Maki, Shojiro,Niwa, Haruki,Ohashi, Mamoru
experimental part, p. 90 - 99 (2011/04/12)
Coelenterazine analogs 3a3e possessing various substituents at the para-position of the 6-phenyl group (R = CF3, F, H, OMe, and NMe 2) were synthesized, and the chemiluminescent properties of 3a3e in dimethyl sulfoxide (DMSO) were investigated quantitatively. Chemiluminescence maxima observed in the range of 454478nm showed a bathochromic shift as the electron-donating ability of R increased. Chemiluminescence quantum yields (φCL) were obtained in the range of 0.00060.0018. The analog 3a possessing the electron-withdrawing CF3 group showed a slight decrease in its φCL value. The fluorescence quantum yields (φF) of the light emitter, 2-acetamidopyrazine anions 4a --4e- , were observed in the range of 0.0050.21 and showed substituent dependency in that the increment in the electronwithdrawing ability of R decreases the φF value. The efficiency of generation of the singlet-excited 4a--4e- (φS) showed a small change in the range of 0.0080.015. From these quantitative analyses of the quantum efficiencies, we found that an electron-donating substituent R is not required for the efficient generation of a singlet-excited light emitter, but is required for the high φF of the emitter.
