Determination of the chiral purity of dipeptide isosteres containing a reduced peptide bond by gas chromatographic analysis.
The stereochemical purity of psi (CH2-NH) dipeptides has been determined using gas chromatography-mass spectrometry. Different structures were found due to the derivatization procedures. A selective preparation of the linear bistrifluoroacetylated derivative and the monotrifluoroacetylated lactam makes it possible to monitor the chiral purity of the pseudodipeptides synthesized. Racemization occurring during peptide hydrolysis can be differentiated from racemization during the synthesis by using deuterium labelling. The method allows the optimization of the synthesis protocols and will be useful for further monitoring of the chiral purity of the pseudopeptides synthesized.
Eenheid Organische Chemie (ORGC), Vrije Universiteit Brussel, Belgium.
M
M
De Bondt
J
J
Couder
L
L
Van der Auwera
M
M
Van Marsenille
M
M
Elseviers
N
N
Delaet
G
G
Laus
D
D
Tourwé
G
G
van Binst
D002849:Chromatography, Gas; D004151:Dipeptides / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry; D006868:Hydrolysis; D013237:Stereoisomerism
D004151:Dipeptides