Arsine, trimethyl oxide

Arsine, trifluorohaloethylenebis(dimethyl-, 2, 1006 Arsine, trimethyl-, 2, 1005,1006 oxide... 

According to Challenger (127), arsenate is transformed to trimethyl-arsine by the mold Scopulariopsis brevicaulis, by sequential reduction and oxidative methylation of the arsenic species (Fig. 7). The proposed intermediates in the pathway were MMA, DMA, and TMAO. Although Challenger could not detect these compounds, when they were added to a culture of S. brevicaulis trimethylarsine was formed. Challenger (129) considered that the likely source of methyl groups was S-adeno-sylmethionine (AdoMet), which had previously been identified as an... 

Four arsenic species common in natural samples are arsenate, arsenite, methanearsonic acid (MMAA) and dimethylarsinic acid (DMAA). These species possess different chemical properties which affect the mobility of arsenic in natural systems. For example, methanobacteriurn form trimethyl arsine from DMAA faster than fromMMAAor arsenate 3) and arsenate and MMAA are more strongly adsorbed than DMAA on alluvial soils ( ). Transformation between the different oxidation states and species of arsenic may occur as a result of chemical or biochemical reactions (J, 2, 7, 9). Inorganic chemical... 

Andreae described a method for the sequential determination of arsenate, arsenite, mono-, di- and trimethyl arsine, MMAA, DMAA and trimethylarsine oxide in natural waters with detection limits of several ng/1. The arsines are volatilized from the sample by gas stripping the other species are then selectively reduced to the corresponding arsines and volatilized. The arsines are collected in a cold trap cooled with liquid nitrogen. They are then separated by slow warming of the trap or by gas chromatography, and measured with atomic absorption, electron capture and/or flame ionization detectors. He found that these four arsenic species all occurred in natural water samples. 

R represents hydrogen atoms, or aliphatic or aromatic organic radicals and X represents an electronegative atom or radical (F, Cl, Br, I, OH, etc.). Arsenous acid is an example of the most oxidized member of Category I, in which one finds, as derivatives, tetraalkyl arsonium compounds, cacodyl derivatives, and esters of arsenous acids. Arsenic acid is an example of the most oxidized members of Category II, and trimethyl arsine oxide (CHjjjAsO is an example of one of the lowest oxidation states. The practically nontoxic compound arsenobetaine is the main form of arsenic in most species of fish and crustaceans (Edmonds and Francesconi 1988). 

C2 H35LiN2, Fluorenyllithium bisquinuclidine, 38B, 115 C2 yHeiAS9Ca2Clft02 5 f Tri-M (trimethylarsine oxide)-hexakis(trimethyl-arsine oxide)dicalcium(II) tetraperchlorate, 43B, 895 C28H24ClNaOi0f Bis(phenacylkojate)sodium chloride, 42B, 577 C2 8H2 4IKO10 f Bis(5-phenacyloxy-2-hydroxymethyl-4H-pyran-4-one)potassium iodide, 40B, 668... 

Dimethyl arsenic acid yields predominantly dimethylarsine, while methylarsonic acid yields predominantly methylarsine and trimethyl-arsine oxide yields predominantly trimethylarsine. 

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