1204-72-4Relevant academic research and scientific papers
Fluorescence Properties of Benz[f]indole, a Wavelength and Quenching Selective Tryptophan Analog
Liu, Bo,Barkley, Mary D.,Morales, Guillermo A.,McLaughlin, Mark L.,Callis, Patrik R.
, p. 1837 - 1843 (2000)
Tryptophan analogues with unique spectral and photophysical properties offer intrinsic fluorescent probes for studying peptide-protein and protein-protein interactions. Two benzannulated indole derivatives, benz-[f]indole and 3-methylbenz[f]indole, were synthesized and their fluorescence was characterized. The absorption and fluorescence emission spectra are red shifted about 75 nm to the red of the spectra of indole and 3-methylindole. INDO/S-CIS computations indicate two nearly degenerate lowest excited singlet states, analogous to the 1La and 1Lb transitions of indoles but with almost collinear transition moments. The limiting excitation anisotropy spectra increase and the emission anisotropy spectra decrease with increasing wavelength, probably due to vibronic coupling of the 1La state with higher energy B states. Solvent and temperature effects on the wavelength of maximum emission argue that emission occurs from 1La in polar environments. The fluorescence quantum yields and lifetimes are high and essentially independent of temperature and solvent isotope. Quantum yields are 0.80 for both compounds. Lifetimes are 19 ns for benz[f]indole and 25 ns for 3-methylbenz[f]indole. The fluorescence is not quenched by most protein functional groups in Stern-Volmer experiments, though it is quenched weakly by strong electron acceptors, such as histidine and cysteine. These results indicate that two nonradiative processes of indoles, solvent quenching and excited-state proton transfer, are not important decay pathways of benzannulated indoles. A third nonradiative process, excited-state electron transfer, occurs in benzannulated indoles under more limited conditions than in indoles.
Arylmethyl radicals from arylmethoxybromodiazirines
Moss, Robert A.,Fu, Xiaolin
, p. 3353 - 3356 (2007/10/03)
(Chemical Equation Presented) Photolytic decompositions of 3-arylmethoxy-3-bromodiazirines afford arylmethyl radicals by homolyses of the diazirines' excited states.
