Mass spectrometry of analytical derivatives. 1. Cyanide cations in the spectra of N-alkyl-N-perfluoroacyl-alpha-amino acids and their methyl esters

Published

July 15, 2015

Author(s)

Nino G. Todua, Kirill V. Tretyakov, Anzor I. Mikaia

Abstract

The central mission for the development of the NIST/NIH/EPA mass spectral library (The Library) is the acquisition of reference GC-MS data for important compounds and their chemical modification products 1. Addition of reliable reference data of various derivatives of amino acids to The Library, and study of their behavior under electron ionization conditions may be useful for their identification, structure elucidation and better understanding of the data obtained when the same derivatives are subjected to other ionization methods. N-Alkyl-N-perfluoroacyl derivatives of amino acids readily produce previously unreported alkylnitrilium cations of a composition [HC≡ N-Alkyl]+. Homologous [HC≡ N-Aryl]+ cations are typical for corresponding N-aryl analogs. The formation of other ions characteristic for these derivatives involves oxygen rearrangement giving rise to ions [CnF2n+1-C≡N+-CnH2n+1] and [CnF2n+1-C≡N+-Aryl]. Introduction of an N-benzyl substituent in a molecule favors a process producing benzylideneimminium cations. L-Threonine and L-cysteine derivatives exhibit more fragmentation pathways not typical for other α-amino acids; additionally, the Nω-amino group in L-lysine directs the dissociation process and provides structural information on the substitution at amino functions in the molecule

Citation

European Journal of Mass Spectrometry

Volume

21

Issue

3

Pub Type

Journals

Download Paper

Local Download

Keywords

amino acids, alkyl/perfluoroacyl derivatives, electron ionization, mass spectrometry, nitrilium ions

Citation

Todua, N. , Tretyakov, K. and Mikaia, A. (2015), Mass spectrometry of analytical derivatives. 1. Cyanide cations in the spectra of N-alkyl-N-perfluoroacyl-alpha-amino acids and their methyl esters, European Journal of Mass Spectrometry, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=918414 (Accessed April 18, 2024)