On-resin head-to-tail cyclization of cyclotetrapeptides: optimization of crucial parameters.

J Pept Sci

Dipartimento di Chimica Organica Ugo Schiff, Università di Firenze, and CNR-ICCOM, Polo Scientifico, 1-50019 Sesto Fiorentino (FI), Italy.

Published: April 2004

Cyclotetrapeptides are constrained cyclic peptides whose synthesis is considered a difficult task. A methodology based on on-resin head-to-tail cyclization by anchoring the side chain of a trifunctional amino acid was investigated. A series of model cyclotetrapeptides containing the RGD sequence cyclo(Xaa-Arg-Gly-Asp) (Xaa = Ala, Phe, Phg, D-Ala, D-Phe, D-Phg) was synthesized with no cyclodimerization by-products. An evaluation and optimization study of all of the parameters directly involved in the ring closure was performed.

Download full-text PDF

Source
http://dx.doi.org/10.1002/psc.512DOI Listing

Publication Analysis

Top Keywords

on-resin head-to-tail
8
head-to-tail cyclization
8
cyclization cyclotetrapeptides
4
cyclotetrapeptides optimization
4
optimization crucial
4
crucial parameters
4
parameters cyclotetrapeptides
4
cyclotetrapeptides constrained
4
constrained cyclic
4
cyclic peptides
4

Similar Publications

Imidazolones represent an important class of heterocycles present in a wide range of pharmaceuticals, metabolites, and bioactive natural products and serve as the active chromophore in green fluorescent protein. Recently, imidazolones have received attention for their ability to act as a nonaromatic amide bond bioisotere which improves pharmacological properties. Herein, we present a tandem amidine installation and cyclization with an adjacent ester to yield (4)-imidazolone products.

View Article and Find Full Text PDF

Flow-Based Fmoc-SPPS Preparation and SAR Study of Cathelicidin-PY Reveals Selective Antimicrobial Activity.

Molecules

February 2023

School of Chemical Sciences and School of Biological Sciences, The University of Auckland, 23 Symonds St., Auckland 1142, New Zealand.

Antimicrobial peptides (AMPs) hold promise as novel therapeutics in the fight against multi-drug-resistant pathogens. Cathelicidin-PY (NH-RKCNFLCKLKEKLRTVITSHIDKVLRPQG-COOH) is a 29-residue disulfide-cyclised antimicrobial peptide secreted as an innate host defence mechanism by the frog (PY) and reported to possess broad-spectrum antibacterial and antifungal properties, exhibiting low cytotoxic and low hemolytic activity. Herein, we detail the total synthesis of cathelicidin-PY using an entirely on-resin synthesis, including assembly of the linear sequence by rapid flow Fmoc-SPPS and iodine-mediated disulfide bridge formation.

View Article and Find Full Text PDF

Here we report a method to synthesize C-terminally modified peptides on resin. A four-component Ugi reaction of isocyanide resin, an Fmoc-protected amino acid, an amine, and a 6-nitroveratrylaldehyde gives C-terminal photocaged peptide amides, which can be photolyzed to generate C-terminal peptide amides. Changing the amine component in the Ugi reaction gives peptides with different C-terminal modifications including substituted anilides, alkyne, and azide.

View Article and Find Full Text PDF

Cyclization and Self-Assembly of Cyclic Peptides.

Methods Mol Biol

January 2022

Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.

Article Synopsis
  • Cyclic peptides can fold into various structures, making them useful in fields like biomedicine, nanoelectronics, and catalysis.
  • The text describes methods for creating cyclic peptides using protected linear structures and emphasizes on-resin procedures for cyclization.
  • Key characterization techniques, such as AFM, TEM, and fluorescence microscopy, are highlighted for studying the assembly and dynamics of cyclic peptides, including their formation into nanotubes.
View Article and Find Full Text PDF

Three Methods for Peptide Cyclization Via Lactamization.

Methods Mol Biol

January 2022

Laboratorio Química Farmacéutica, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo, Uruguay.

Lactamization is the key step in the synthesis of many compounds with macrocyclic structure. As the interest for these types of molecules grows in various fields such as drug discovery and nanomaterials, different methodologies to access them are being developed. Three different strategies to obtain cyclic peptides via lactamization are described in this chapter: solution-phase macrocyclization following solid-phase peptide synthesis (SPPS) of the linear precursor, SPPS and on-resin cyclization on the 2-chlorotrityl chloride (2-CTC) resin, and SPPS and on-resin cyclization by native chemical ligation on the amino-PEGA resin.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!