Résumé
This paper discusses the application of a method developed for cyclic peptide synthesis using allyl-based side-chain-protecting groups to obtain a so-called tailed cyclic peptide, a cyclic peptide bearing a side-chain anchoring tail. The method used for the synthesis of cyclo[-D-Val-Arg-Gly-Asp-Asp(-εAhx-Cys-NH2)-] incorporates the α-allyl-protected aspartic acid Fmoc-L-Asp-OAl. A major side reaction, resulting in aspartimide formation, was observed when Fmoc-L-Asp-OAl was incorporated into the sequence at the N-terminus of 6-aminohexanoic acid (εAhx). This side reaction leads to an aspartimidyl linear peptide with the same molecular weight as the expected cyclized peptide. Additionally, the undesired peptide contains a free amino terminus, which was responsible for further side reactions during the subsequent steps of the synthesis, mainly tetramethylguanidinium formation (M+98) in TBTU-induced cyclization, and acetylation (M+42). © 1996 ESCOM Science Publishers B.V.
langue originale | Anglais |
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Pages (de - à) | 89-97 |
Nombre de pages | 9 |
journal | International Journal of Peptide Research and Therapeutics |
Volume | 3 |
Numéro de publication | 2 |
Etat de la publication | Publié - 1996 |