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Updated: May 11, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
C → N and N → C solution phase peptide synthesis using the N-acyl 4-nitrobenzenesulfonamide as protection of the
Rosaria De Marco1, Mariagiovanna Spinella, Anna De Lorenzo
1Dipartimento di Farmacia e Scienze della Salute e della Nutrizione, Università della Calabria, Ed. Polifunzionale, 87036, Arcavacata di Rende, Italy.
Abstract:
In this paper we describe a solution phase peptide synthesis strategy using the 4-nitrobenzenesulfonamido/N-methyl-4-nitrobenzenesulfonamido group as a protecting/activating system of the carboxyl function. The 4-nitrobenzenesulfonamido group is stable during peptide chain elongation (Fmoc chemistry). The N-aminoacyl or N-dipeptidyl-4-nitrobenzensulfonamides, when activated by methylation, can be easily coupled with another amino acid or reconverted into the free-carboxyl function amino acids or peptides. This activatable protecting group allows both the C → N and the N → C direction solution phase peptide synthesis. We also verified that the absolute configuration at the chiral centers does not change during the coupling reactions.
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