ISSN:
1052-9306
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The N-acetyl-, N-trifluoroacetyl-, N-pentafluoropropionyl- and N-heptafluorobutylamino derivatives of the tripeptide valyl-alanyl-leucine have been synthesized in every combination with the carboxy derivatives O-methyl ester, O-(1-H,H)-trifluoroethyl ester, O-(1-H,H)-pentafluoropropyl ester and O-(1-H,H)-heptafluorobutyl ester. These 16 derivatives have been mass measured after negative ionization using a 10% CO2/Ar moderator gas mixture in an electron impact ion source of a VG-ZAB-2F mass spectrometer. The fragmentation behaviour of the peptide derivatives have been studied by negative linked-scan, negative mass-analysed ion kinetic energy and charge inversion mass spectrometry. Most detected sequence ions originate from N-terminal fragments. Recorded anion currents and linked-scan measurement have shown that fluoro residues at the C-terminus increase the intensities of sequence ions, whereas N-terminal perfluoroalkyl derivatives generate [M - HF]- and [M - 2HF]- ions. The abundances of these fragment ions increase with increasing molecular weight of the N-terminal residues. The best sequence information with intense anion currents has been recorded with the peptide derivative N-trifluoroacetylamino-O-hepatafluorobutyl ester.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bms.1200170602
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