A general strategy for the synthesis of N-peptide-6-amino-D-luciferin conjugates has
been developed. The applicability of the strategy was demonstrated with the preparation
of a known substrate, N-Z-Asp-Glu-Val-Asp-6-amino-D-luciferin (N-Z-DEVD-aLuc).
N-Z-DEVD-aLuc was obtained via a hybrid liquid/solid phase synthesis method,
in which the appropriately protected C-terminal amino acid was coupled to
6-amino-2-cyanobenzothiazole and the resulting conjugate was reacted with D-cysteine
in order to get the protected amino acid-6-amino-D-luciferin conjugate, which was then
attached to resin. The resulting loaded resin was used for the solid-phase synthesis
of the desired N-peptide-6-amino-D-luciferin conjugate without difficulties, which was
then attested with NMR spectroscopy and LC-MS, and successfully tested in a
bioluminescent system