ISSN:
1075-2617
Keywords:
peptide synthesis
;
cysteine
;
racemization
;
enantiomeric resolution
;
capillary electrophoresis
;
gas chromatography
;
Chemistry
;
Biochemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A new method has been developed for the rapid determination of D-cysteine contents in synthetic peptides. It is based on the reduction of cystine residues, when present, with tris- alkylphosphines, selective derivatization of the cysteine residues with 4-vinylpyridine, followed by acid hydrolysis of the (4-pyridylethyl)cysteine -peptides. Baseline enantiomeric resolution of theD,L-S-β-(4-pyridylethyl)cysteine, and thus quantification ofD- enantiomer contents at levels ≤1%, is easily achieved by capillary zone electrophoresis exploiting the host-guest complexation principle with crown ethers or by gas chromatography on chiral glass capillary columns upon conventional derivatization of the hydrolysate. The acid-stability of the (4-pyridylethyl)cysteine derivative prevents racemization via thiazoline intermediates and allows for standardization of the acid hydrolysis-dependent racemization.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/psc.83
