505-60-2

Three aqueous samples containing sulfonium chloride salts of both mustard gas (2,2'-dichlorodiethylsulfide) and its simulant 2-chloroethyl ethyl sulfide have been characterized by gas chromatography/mass spectrometry (GC/MS).Theese salts decompose thermallly to the sorresponding 2-chloroethyl and 2-hydroxyethyl sulfides, therefore GC/MS analysis is not indicative of the true composition of these solutions.Small amounts of dithioethers characteristic of the decomposition of the dimeric salts were also detected.Electron Impact (EI) ionization produces a more intense molecular ion than methane chemical ionization (CI) for the dithioethers because of the ease of formation of sulfonium ions during chemical ionization.The composition products of four aged samples of 2-chloroethyl sulfides (RSCH2CH2Cl where R=methyl, ethyl, phenyl and benzyl groups) were also characterized by GC/MS, which indicated that decomposition of these compounds may proceed via dimeric sulfonium ions.Mustard gas was detected in all but one of the samples, providing evidence for secondary sulfonium cation formation in the degradation prcess.Keywords: Sulfonium chlorides; 2-chloroethyl sulfides; degradation; dimeric sulfonium cations; GC/MS characterization.

A group of biologically active 1-aryl-3-triazenes has been synthesized.The rates of decomposition of a selected triazene, determined polarographically, increase with decrease in pH from 7.1 to 5.1.The products of aqueous decomposition have been analyzed by GC and GC-MS.A selectively deuterated triazene is found helpful in discriminating between alternative decomposition pathways.The data are consistend with initial protonation of the triazene and generation therefrom of a S-(2-chloroethyl)thioethyl cation (or its kinetic equivalent) which undergoes rearrangements as detected by deuterium scrambling.A second competing pathway may involve cyclization of the triazene to a 1-aryl-1,2,3-triazathiaoctene intermediate which then undergoes nucleophilic opening with attendant loss of nitrogen.These triazenes readily esterify 3,5-dinitrobenzoic acid and diethyl phosphate in etheral solutions.The use of deuterium labelled triazene indicates that these triazenes esterify predominantly via ion-pair mechanism and SN2 displacement is the minor pathway.A selected triazene is observed to alkylate the N3-position of triacetyluridine, also via a combination of ion-pair and SN2 displacement mechanisms as studied by the application of deuterium labelling.These studies are expected to assist in the interpretation of the cytotoxic effects of these triazenes.

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