Backbone cyclization: A new method for conferring conformational constraint on peptides
Related Experiment Video
Updated: Aug 7, 2026

Development of a Backbone Cyclic Peptide Library as Potential Antiparasitic Therapeutics Using Microwave Irradiation
Published on: January 27, 2016
1Department of Organic Chemistry, Hebrew University of Jerusalem, Israel.
Abstract:
This article describes a new concept of medium- and long-range cyclization of peptides through "backbone cyclization." In this approach, conformational constraints are conferred on a peptide by linking omega-substituted alkylidene chains replacing N(alpha) or C(alpha) hydrogens in a peptidic backbone. Backbone cyclization, which is divided into N-backbone and C-backbone cyclizations, allow for new modes of cyclization in addition to the classical ones that are limited to cyclization through the side chains and/or the amino or carboxyl terminal groups. The article also describes the application of the N-backbone cyclization to the active region of substance P. Conformational constraints of this peptide by the classical cyclization modes led to inactive analogues whereas N-backbone cyclization provided an active, selective, and metabolically stable analogue.
Related Concept Videos
Protein Folding
Peptide Bonds
Conformations of Cyclohexane
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal tetrahedral value,...
Chair Conformation of Cyclohexane
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this staggered...
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...

