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High fluorescence emissions of some natural benzofurane derivatives isolated from Styrax officinalis

WOS: 000088382300011The fluorescent properties of several natural benzofuran derivatives, egonols, isolated from Styrax officinalis, were determined. The studied egonol derivatives were found to be effective UV organic luminophores, with quantum yields of near to unity, phi(f) = 0.92. The fluorescence quenching experiments with electron donor molecules of aniline, N,N-dimethylaniline and carbazolocarbazole, presented very high efficiency of quenching at above diffusion quenching rates of 4.5x10(10), 2.1x10(x) and 5.6x10(12) s(-1)mol(-1), respectively. A strong electron acceptor molecule, tetranitrofluorenone, presented quenching rate of 2.6x10(11) s(-1)mol(-1). It is concluded that the first excited singlet state of egonol molecule is a more efficient electron acceptor