L-phototryptophan

Article abstract of DOI:10.1002/ejoc.201201726

Phototryptophan is a new photoactivatable amino acid designed to be incorporated into tryptophan-containing peptides for photoaffinity labeling. The synthesis of phototryptophan starts from 6-bromoindole with the installation of an 1-azi-2,2,2-trifluoroethyl moiety, followed by microwave-assisted condensation with serine under mild conditions. Separation of the N-acetylated enantiomers was possible by employing Aspergillus aminoacylase. Differential scanning calorimetry showed that phototryptophan is thermally stable up to 100 °C. Boc-L-Phototryptophan was used to assemble a diazirine analog of the marine natural product hemiasterlin. L-Phototryptophan carries a photoactivatable diazirinyl substituent in the indole 6-position and could become interesting for photoaffinity labeling. The thermally stable compound survives conditions of peptide synthesis and was incorporated into a photoderivative of the marine natural product hemiasterlin. Copyright