@article {1112,
	title = {Chromatographic separation and identification of products from the reaction of dimethylarsinic acid with hydrogen sulfide},
	journal = {Chemical Research in Toxicology},
	volume = {18},
	number = {12},
	year = {2005},
	note = {ISI Document Delivery No.: 004XYTimes Cited: 24Cited Reference Count: 44},
	month = {Dec},
	pages = {1821-1829},
	type = {Article},
	abstract = {The reaction of dimethylarsinic acid (DMA(V)) with hydrogen sulfide (H2S) is of biological significance and may be implicated in the overall toxicity and carcinogenicity of arsenic. The course of the reaction in aqueous phase was monitored, and an initial product, dimethylthioarsinic acid, was observed by using LC-ICP-MS and LC-ESI-MS. Dimethylarsinous acid was observed as a minor product. A second slower-forming product was identified, and the electrospray mass chromatograms for this species produced ions at m/z 275, 171, and 137 in positive mode. To aid in the identification of this slower-forming product, crystalline standards of sodium dimethyldithioarsinate and dimethylarsino dimethyldithioarsinate were prepared and re-characterized by using improved spectroscopic and structural analysis techniques. An aqueous solution of sodium dimethyldithioarsinate produced a single major chromatographic peak that matched the retention time (7.6 min) of the slower-forming product and contained similar molecular ions at m/z 275, 171, and 137 via LC-ESI-MS. The dimethylarsino dimethyldithioarsinate standard produced four aqueous phase species one of which coeluted with the slower forming product. This coeluting peak also produced the identical ESI-MS ions as the slower-forming product of DMA(V) + H2S. ESI-MS/MS experiments conducted on sodium dimethyldithioarsinate in deuterated water produced molecular ions at m/z 276, 173, and 137. Subsequent collisionally activated dissociation (CAD) experiments on m/z 276 did not produce a product ion at m/z 173. These data indicate that two different species are present in solution, while NMR data indicate that only dimethyldithioarsinic acid exists in aqueous solutions. This discrepancy was investigated by conducting NMR studies on the acidic solution of sodium dimethyldithioarsinate after taking this solution to dryness. The resolubilized solution produced a proton NMR signal characteristic of dimethylarsino dimethyldithioarsinate. Therefore, it was concluded that the ESI-MS ion at m/z 275 associated with the slowly forming second reaction product and the sodium dimethyldithioarsinate compound is a product of the ESI desolvation process.},
	keywords = {CRYSTAL-STRUCTURE, DIMETHYLDITHIOARSINATE, GLUTATHIONE, METABOLITE, ORGANIC ARSENIC COMPOUNDS, RATS, REARRANGEMENT, TOXICITY, TRIMETHYLARSINE OXIDE, urine},
	isbn = {0893-228X},
	url = {<Go to ISI>://000234787200005},
	author = {Fricke, M. W. and Zeller, M. and Sun, H. and Lai, V. W. M. and Cullen, W. R. and Shoemaker, J. A. and Witkowski, M. R. and Creed, J. T.}
}
@article {797,
	title = {Do arsenosugars pose a risk to human health? The comparative toxicities of a trivalent and pentavalent arsenosugar},
	journal = {Environmental Science \& Technology},
	volume = {38},
	number = {15},
	year = {2004},
	note = {ISI Document Delivery No.: 842WOTimes Cited: 23Cited Reference Count: 54},
	month = {Aug},
	pages = {4140-4148},
	type = {Article},
	abstract = {Seafood frequently contains high concentrations of arsenic (similar to10-100 mg/kg dry weight). In marine algae (seaweed), this arsenic occurs predominantly as ribose derivatives known collectively as arsenosugars. Although it is clear that arsenosugars are not acutely toxic, there is a possibility of arsenosugars having slight chronic toxicity. In general, trivalent arsenicals are more toxic than their pentavalent counterparts, so in this work we examine the hypothesis that trivalent arsenosugars might be significantly more toxic than pentavalent arsenosugars in vitro. We compared the in vitro toxicity of (R)-2,3-dihydroxypropyl-5-deoxy-5-dimethylarsinoyl-beta-D-riboside, a pentavalent arsenosugar, to that of its trivalent counterpart, (R)-2,3-dihydroxypropyl-5-deoxy-5-dimethylarsino-beta-D- riboside. The trivalent arsenosugar nicked plasmid DNA, whereas the pentavalent arsenosugar did not. The trivalent arsenosugar was more cytotoxic (IC50 = 200 muM, 48 h exposure) than its pentavalent counterpart (IC50 > 6000 muM, 48 h exposure) in normal human epidermal keratinocytes in vitro as determined via the neutral red uptake assay. However, both the trivalent and the pentavalent arsenosugars were significantly less toxic than MMA(III), DMA(III), and arsenate. Neither the pentavalent arsenosugar nor the trivalent arsenosugar were mutagenic in Salmonella TA104. The trivalent arsenosugar was readily formed by reaction of the pentavalent arsenosugar with thiol compounds, including, cysteine, glutathione, and dithioerythritol. This work suggests that the reduction of pentavalent arsenosugars to trivalent arsenosugars in biology might have environmental consequences, especially because seaweed consumption is a significant environmental source for human exposure to arsenicals.},
	keywords = {DIMETHYLARSINIC ACID, DNA-DAMAGE, HUMAN-CELLS, IN-VITRO, INORGANIC ARSENICS, METABOLISM, METHYLATED ARSENICALS, MONOMETHYLARSONOUS ACID MMA(III), ORGANIC ARSENIC COMPOUNDS, SEAWEED},
	isbn = {0013-936X},
	url = {<Go to ISI>://000223035400022},
	author = {Andrewes, P. and Demarini, D. M. and Funasaka, K. and Wallace, K. and Lai, V. W. M. and Sun, H. S. and Cullen, W. R. and Kitchin, K. T.}
}
