Synthesis of a new, highly fluorescent amino acid derivative: N-[(tert-butoxy)carbonyl]-3-[2-(1H-indol-3-yl)benzoxazol-5-yl]-L-alanine methyl ester

A simple method of synthesis of a new. highly fluorescent amino acid deriva tive from the simple and generally available substrates 3-nitro-L-tyrosine and 1H-indole-3-carbaldehyde is described. The obtained compound, N-[(tert- butoxy)carbonyl]-3-[2-(1H-indol-3-yl)benzoxazol-5-yl]-L-alanine methyl este r (4), possesses a high fluorescence quantum yield. The described method il lustrates a new possibility of synthesis of amino acid derivatives possessi ng desirable photophysical properties.