A Safety Catch Linker for Fmoc-based Assembly of Constrained Cyclic Peptides

Ravn, J.; Bourne, G.; Smythe, M. A Safety Catch Linker for Fmoc-based Assembly of Constrained Cyclic Peptides. J. Peptide Sci. 2005, 11, 572-578.

A new safety-catch linker for Fmoc solid-phase peptide synthesis of cyclic peptides is reported. The linear precursors were assembled on a tert-butyl protected catechol derivative using optimized conditions for Fmoc-removal. After activation of the linker using TFA, neutralization of the N-terminal amine induced cyclization with concomitant cleavage from the resin yielding the

cyclic peptides in DMF solution. Several constrained cyclic peptides were synthesized in excellent yields and purities.

Keywords: Cyclic peptides; combinatorial chemistry; safety-catch linker