Mass spectral analysis of N‐oxides of Chemical Weapons Convention related aminoethanols under electrospray ionization conditions

Abstract

N,N'-Dialkylaminoethanols are the hydrolyzed products or precursors of chemical warfare agents such as V-agents and nitrogen mustards, and they are prone to undergo oxidation in environmental matrices or during decontamination processes. Consequently, screening of the oxidized products of aminoethanols in aqueous samples is an important task in the verification of chemical weapons convention-related chemicals. Here we report the successful characterization of the N-oxides of N,N'-dialkylaminoethanols, alkyl diethanolamines, and triethanolamine using positive ion electrospray ionization mass spectrometry. The collision-induced dissociation (CID) spectra of the [M+H](+) and [M+Na](+) ions show diagnostic product ions that enable the unambiguous identification of the studied N-oxides, including those of isomeric compounds. The proposed fragmentation pathways are supported by high-resolution mass spectrometry data and product/precursor ion spectra. The CID spectra of [M+H](+) ions included [MH-CH(4)O(2)](+) as the key product ion, in addition to a distinctive alkene loss that allowed us to recognize the alkyl group attached to the nitrogen. The [M+Na](+) ions show characteristic product ions due to the loss of groups (R) attached to nitrogen either as a radical (R) or as a molecule [R+H or (R-H)] after hydrogen migration.

Mass spectral characterization of the CWC‐related isomeric dialkyl alkylphosphonothiolates/alkylphosphonothionates under gas chromatography/mass spectrometry conditions

“…Of these, the MS detector has been extensively used because of its high sensitivity and versatility. Compounds of polar nature can be analyzed directly by liquid chromatography (LC)/MS or by GC/MS after derivatization . GC/MS analysis is typically performed under electron ionization (EI) or chemical ionization (CI) conditions .…”

Biotransformation of Two β-Secretase Inhibitors Including Ring Opening and Contraction of a Pyrimidine Ring

“…• that is a characteristic neutral loss for N-oxides and N-hydroxyls (Kuffel et al, 2002;Sridhar et al, 2011). On the basis of this observation and the finding of CID product ions at m/z 242, corresponding to loss of the aryl-pyrimidine moiety, and m/z 303, corresponding to loss of pyridine plus one O atom, M1a was proposed to be the pyridine N-oxide.…”

Mass spectrometric study on O(S)-alkyl N,N-dimethylamino alkylphosphonates (alkylphosphonothiolates) for Chemical Weapons Convention verification purposes

“…mass spectra of the CW agents, their precursors and degradation products such as N,N-dialkylaminoethanols, alkylphosphonates, N,N-dialkylphosphoramidates, sulfur and nitrogen mustard, methylphosphonites, N,N-dialkylaminoethane-2-sulfonic acids, Noxides of aminoethanols, N,N-dialkylaminoethane-2-thiols, alkyl methylphosphoric acids [4][5][6][7][8][9][10][11][12][13][14]. One of the CWC-related chemicals is O(S)-alkyl N,N-dimethylamino alkylphosphonates (alkylphosphonothiolates).…”