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1: J Pept Sci. 2003 Aug;9(8):518-26.Links

The aspartimide problem in Fmoc-based SPPS. Part II.

Mergler M, Dick F, Sax B, Stähelin C, Vorherr T.

BACHEM AG, Hauptstr. 144, CH-4416 Bubendorf, Switzerland.

The sequence dependence of base-catalysed aspartmide formation during Fmoc-based SPPS was systematically studied employing the peptide models H-Val-Lys-Asp-Xaa-Tyr-Ile-OH. The extent of formation of aspartimide and related by-products was determined by RP-HPLC. Considerable amounts of by-products were formed in the case of Xaa = Asp(OtBu), Arg(Pbf), Asn(Mtt), Cys(Acm) and unprotected Thr. Aspartimide formation could be diminished by incorporation of Asp(OMpe) or by employing milder methods for Fmoc cleavage, e.g. hexamethyleneimine/N-methylpyrrolidine/HOBt/NMP/DMSO 4:50:4:71:71 (v/v/w/v/v).

PMID: 12952393 [PubMed - indexed for MEDLINE]