Synthesis, Resolution and Charge‐donor Properties of Six Tryptophan Analogues

Abstract

In order to investigate the special function of tryptophan in peptide hormones, six tryptophan analogues have been synthesized, in which structural resemblance has been grossly retained and potentially essential properties have only partially been varied. The l‐enantiomers have been isolated after enzymatic digestion of racemic dipeptide derivatives, and charge‐transfer properties of the compounds have been studied.

Fluorescent Analogs of Biomolecular Building Blocks: Design, Properties, and Applications

“…Both 5OHTrp ( 5.11 ) and 7azaTrp ( 5.12 ) display a 20 nm bathochromic shift of their absorption maximum relative to tryptophan, facilitating selective excitation . Two other examples, benzofuranylalanine (BfAla, 5.13 ) and benzothiophenyl (BtAla, 5.14 ), only differ from tryptophan in their ring heteroatom. − Tirrell and co-workers have incorporated BtAla ( 5.14 ) and other tryptophan mimics to modify the spectral properties of fluorescent proteins . These and other tryptophan mimics have been discussed in reviews. ,,, …”

“…332 Two other examples, benzofuranylalanine (BfAla, 5.13) 333 and ben-zothiophenyl (BtAla, 5.14), 334 only differ from tryptophan in their ring heteroatom. [335][336][337] Tirrell and co-workers have incorporated BtAla (5.14) and other tryptophan mimics to modify the spectral properties of fluorescent proteins. 338 These and other tryptophan mimics have been discussed in reviews.…”