Polychlorinated phenyl ether

The toxic mushroom Russula subnigricans produces the novel polychlorinated phenyl ethers, russuphelins A-F (1928-1933), some of which (B, C, D) exhibit cytotoxicity against P388 leukemia cells (1672, 1800). Further study of this mushroom uncovered the presence of the optically active russuphelol (1934) (1801). The terrestrial cyanobacterium Fischerella ambigua has afforded ambigol C (1935) (1654), which is an isomer of the previously described ambigols A and B (1). 

The role of polychlorinated gem-dichlorocyclohexadienones as reaction intermediates which can then produce desired me/a-chlorinated products or imdesired coupled products has been described.17 Chlorination of phenol and sometimes the ether complicates the hydrolysis of some primary alkyl phenyl ethers in concentrated aqueous perchloric acid solution.18 Unexpected chlorination has also been established in the reaction of 2-amino-5-chlorobenzophenone with HC1 in aqueous methanol (1 1 v/v), 2-amino-3,5-dichlorobenzophenone being amongst the products.19... 

Polychlorinated diphenyl ethers (PCDE), also called bis(chlorophenyl) ethers and chlorodiphenyl oxides, are neutral aromatic compounds which resemble structurally polychlorinated biphenyls (PCB), except that one oxygen atom connects the phenyl rings. The empirical formula of the PCDEs is C12H10 nClnO, where n = 1-10. The structural formula of the PCDEs is given in Fig. 1. 

Polychlorinated quaterphenyl ethers (PCQEs) have been identified in Yusho and Yu-Cheng oils. This class of compounds does not seem to have been tested for toxicity but structure/activity relationships do not predict that they should be particularly toxic. Nevertheless, cyclization to a phenyl substituted dibenzofuran possibly could yield a toxic product. The likelihood of the cyclization reaction provides a measure for the concern to be accorded the presence of ether precursors. 

The detection and quantification of polychlorinated dibenzo-p-dioxins, and in particular the 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (2,3,7,8-TCDD), is a major application for double-focusing magnetic-sector mass spectrometers. Despite extensive clean-up procedures, samples still contain compounds such as polychlorinated biphenyls and benzyl phenyl ethers, which have the same nominal masses as the compounds of interest. The sample is spiked with a known amount of the isotope labelled form of 2,3,7,8-TCDD, introduced via gas chromatography and recorded by high-resolution mass spectrometry. The measurement is quantified by comparison of the native dioxin response to that from the C-labelled form, and verified by confirmation of the ratio of the major isotopes of both the native and the C-labelled dioxins. At 10 000 resolving power (10% valley definition) the detection level for 2,3,7,8-TCDD is about 1 femtogram, or 3 attomole (Figure 6). 

Phenyl methylpolysiloxane Polycyclic aromatic hydrocarbons, disinfection by-products, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and dibenzofurans, organochlorine pesticides, polybrominated biphenyls, polybrominated diphenyl ethers, chlorinated paraffins, methyl-fert-butyl-ether... 

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