Protected Peptide Segments Research Articles

Reversed-phase high-performance liquid chromatography of protected peptide segments

There is little evidence that reversed-phase high-performance lquic chromatography can be successfully used in the analysis of protected peptide segments. The use of C 18 and CN packings and mobile phases containing water-acetonitrile with or without propionic acid in the separation of complex mixtures of synthetic protected peptides is reported. CN packings show a lower efficiency and exhibit poorer resolution than C 18 packings but provide different separations. The addition of propionic acid to the mobile phase increases the retention time of peptides but also provides dramatic and useful changes in selectivity. Retention is not related to the molecular mass of the protected peptides but mainly to their hydrophobicity.

Convergent solid phase peptide synthesis IV. : Synthesis of the 35–43 and 32–34 protected segments of the toxin II of androctonus australis hector

The protected peptide segments corresponding to the sequences 35–43 and 32–34 of toxin II of the scorpion Androctonus australis Hector have been synthesized on a p -alkoxybenzyl ester resin using the base-labile Fmoc α-amino protection and HF-labile side chain protecting groups. Crude peptides obtained after trifluoroacetic acid cleavage have been purified by solvent extraction, dimethylacetamide-water precipitation and semi-preparative reversed phase HPLC. Both synthetic and purification protocols have been optimized for good yields and high purity. Fast atom bombardment mass spectrometry has proved to be a very useful technique to characterize protected peptide segments.

Polymer-supported biopolymer synthesis: 4. Synthesis of dynorphin (1–13) by condensation of protected peptide segments prepared by high-load solid (gel) phase methods

Total synthesis of the opioid tridecapeptide dynorphin (1–13) has been effected by solution acyl azide condensation of peptide segments corresponding to dynorphin (1–5) and dynorphin (6–13). The latter were prepared by stepwise high-load solid (gel) phase synthesis using a phenolic poly(acryloylmorpholine)-based support. The target peptide was deprotected by catalytic transfer hydrogenation.

Reversed phase h.p.l.c. of fully protected, synthetic βh- endorphin peptide segments of extreme hydrophobicity

Reversed-phase high-pressure liquid chromatography (h.p.l.c.) using trifluoroethanol/water as eluent has been used successfully in the analysis of two fully protected peptide segments of extreme hydrophobicity, β h-endorphin (17–26) and β h-endorphin (18–26).

Synthesis of protected peptide segments and their assembly on a polymer-bound oxime: application to the synthesis of a peptide model for plasma apolipoprotein A-I

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of protected peptide segments and their assembly on a polymer-bound oxime: application to the synthesis of a peptide model for plasma apolipoprotein A-ISatoe Hase Nakagawa and Emil Thomas KaiserCite this: J. Org. Chem. 1983, 48, 5, 678–685Publication Date (Print):March 1, 1983Publication History Published online1 May 2002Published inissue 1 March 1983https://doi.org/10.1021/jo00153a012RIGHTS & PERMISSIONSArticle Views215Altmetric-Citations67LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-Alerts Get e-Alerts

Polymer-supported biopolymer synthesis: 1. High load solid (gel) phase strategy for peptide synthesis with a phenolic poly(acryloylmorpholine)-based support

An efficient, low-cost, reaction strategy for the solid (gel) phase synthesis of peptides and protected peptide segments has been developed. The strategy involves the use of a new poly(acryloylmorpholine)-based phenolic support matrix, Koch-Light Peptide Resin A. Illustrative syntheses of N-terminal Boc- and Z-protected[Leu]- enkephalin derivatives, including C-terminal acid hydrazides and esters, are described. The strategy, which is effective for the synthesis of peptides at high matrix loadings, is adopted readily for large-scale application.

Synthesis of human beta-endorphin in solution using benzyl-type side chain protective groups.

A solution synthesis of human beta-endorphin (beta-EP) was carried out by condensation of protected peptide segments bearing N alpha-tert.-butyloxycarbonyl groups and benzyl-derived groups for the protection of functionalities in amino acid side chains. Five intermediate segments were assembled in a stepwise manner starting at the carboxyl terminus. Thus, the segment of sequence region (27-31) was coupled to segment (22-26) by the azide method. Segment (19-21) was incorporated into the growing chain by azide coupling, and segment (10-18) by dicyclohexylcarbodiimide coupling in the presence of 1-hydroxybenzotriazole (DDC-HOBt). Solubility problems in condensing the ensuing 22-peptide with segment (1-9) by DDC-HOBt were overcome by using a dimethylformamidephenol mixture as a solvent. Protecting group cleavage by Na in liquid NH3 was much superior to liquid HF which gave rise to many decomposition products. Homogeneous betah-EP indistinguishable from authentic material in physiochemical and biological properties, was obtained in a single preparative reversed phase liquid chromatographic step after protecting group cleavage.