J. R. Harrison, C. J. Moody / Tetrahedron Letters 44 (2003) 5189–5191
5191
In summary, we have described the first synthesis of the
unusual macrocyclic peptide fragment of moroidin con-
taining the unique direct link between the tryptophan
indole C-2 and histidine imidazole N-1 residues. Fur-
ther studies are underway.
Acknowledgements
We thank the EPSRC for support of this work, the
EPSRC Mass Spectrometry Centre at Swansea for mass
spectrometric studies, and the EPSRC Chemical Data-
base Service at Daresbury.12
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