Description

• General description: Building block for the introduction of selenocysteine during Fmoc SPPS [1,2,3]. Selenocysteine derivatives can undergo enantiomerization during coupling and can form dehydroalanine and β-piperidinylalanine containing side products during subsequent chain elongation [3]. Therefore, activation methods, such as HBTU or PyBOP which involve the addition of a tertiary, base should be avoided for addition of the Sec and all subsequent residues. Cleavage and side-chain deprotection of Sec-containing peptides can be effected using tFA-m-cresol-thioanisole-EDT-water (80:5:5:5:5)[2] or TFA-water-DCM-TIS (89:5:51) at 4 °C [3]. As the Se-pMeOBzl bond is stable to TFA, these methods result in the formation of the corresponding Sev(pMeOBzl) peptide. Peptides containing two Sec(pMeOBzl) residues can be oxidized directly to the corresponding selenocystinyl peptides by treatment with 5-10% DMSO in TFA [1-3]. Associated Protocols and Technical Articles Cleavage and Deprotection Protocols for Fmoc SPPS Literature references [1] T. Koide, et al. (1993) Chem. Pharm. Bull., 41, 502. [2] T. Koide, et al. (1993) Chem. Pharm. Bull., 41, 1596. [3] D. Besse & L. Moroder (1997) J. Peptide Sci., 3, 442.
• Analysis Note: Color (visual): white to yellow to beigeAppearance of substance (visual): powderIdentity (IR): passes testEnantiomeric purity: ≥ 99.5 % (a/a)Purity (TLC(157A)): ≥ 98 %Assay (HPLC, area%): ≥ 98.0 % (a/a)Solubility (1 mmole in 2 ml DMF): clearly solubleTo see the solvent systems used for TLC of Novabiochem® products please click here.
• Legal Information: Novabiochem is a registered trademark of Merck KGaA, Darmstadt, Germany