Polycyclic aromatic amines

Specific requirements for the end products include tests and migration limits for various types of toxic or harmful compounds such as Michler s ketone (4,4 bis(dimethylamino)benzophenone), 4,4 bis(diethylamino) benzophenone (DEAB), diisopropyhiaphthalenes (DIPNs) phthalates, solvents, partially hydrogenated terphenyls (HTTP), azo colourants, fluorescent whitening agents, primary aromatic amines, polycyclic aromatic hydrocarbons (PAH) and benzophenone. The amounts of these substances should be either below the detection limits or, in some cases (DIPN, HTTP, solvents) as low as can be reasonably achieved. For benzophenone a specific migration limit of 0.1 mg/dm is defined. The requirements generally apply to products intended to be used in contact with aqueous and/or fatty foodstuffs or also with dry, non-fatty foodstuffs (requirements for DIPNs, HTTP, phthalates and solvents). 

Optical absorption spectroscopy of organic radical cations was pioneered by Hoijtink and coworkers and others before the advent of PE spectroscopy, but it was limited for a long time to aromatic amines, polycyclic aromatic hydrocarbons and similar compounds whose radical cations could be generated under stable conditions by chemical oxidation. It was observed that many colourless neutral compounds give rise to intensely coloured radical cations which indicates that excited states of these reactive species lie generally at much lower energy than those of the neutral parent molecules (the most famous example is perhaps Wurster s blue, the radical cation of the colourless tetramethyl-p-phenylenediamine). 

See also Cytochrome P-450 Polycyclic Aromatic Amines Polycyclic Aromatic Hydrocarbons (PAHs). 

In recent years a large number of polyclonal and monoclonal antisera have been produced against adducts or modified DNA samples of a variety of chemical classes, including methylating and ethylating agents, aromatic amines, polycyclic aromatic hydrocarbons (PAH), aflatoxins, psoralens and platinum-ammine complexes (1.2). These antisera have been used to establish highly-sensitive quantitative immunoassays and have been adapted for immunohistochemistry, and electron microscopy. 

In this article we will outline in vitro metabolic studies which have been performed on representatives of several classes of carcinogens. These studies have been selected from the literature through 1979. Metabolic studies which employed various cellular subfractions, cell culture, or organ culture systems will be compared. The effect of species variations on in vitro metabolism will also be considered. The relationship of these in vitro studies to current concepts on metabolic activation and detoxification will be discussed for aromatic amines, polycyclic aromatic hydrocarbons, nitrosamines, hydrazines, azoxy compounds, halogenated hydrocarbons, and carcinogenic natural products. 

Activation-dependent Aromatic amine Polycyclic aromatic hydrocarbon... 

As with the parent aromatic hydrocarbons, diarylamiaes based oa polycyclic aromatic amines also tead to be more harmful. Thus, /V-phenyl-2-naphthylamine [135-88-6] (PBNA) metaboli2es ia the body to produce small amouats of 2-aaphthylamiae, a known carciaogea (37). ACGIH has desigaated PBNA to be an "iadustrial substance suspect of carciaogenic potential for man."... 

Alicyclic dianhydrides are interesting for electronic applications. The polyimides obtained from them are colorless with high transparency in the visible range, exhibit low birefringence,125 and have a low dielectric constant.126 The reactivity of the polycyclic aliphatic dianhydride has been investigated. For example, bicyclo-[2,2,2]-oct-7-ene tetracarboxylic dianhydride reacts quickly with an aromatic amine because the bicyclo-imide is less strained than the corresponding dianhydride.127... 

PGH synthase and the related enzyme lipoxygenase occupy a position at the interface of peroxidase chemistry and free radical chemistry and can clearly trigger metabolic activation by both mechanisms. The peroxidase pathway activates compounds such as diethylstilbestrol and aromatic amines whereas the free radical pathway activates polycyclic hydrocarbons (59). Both pathways require synthesis of hydroperoxide in order to trigger oxidation. 

There are several chemical compounds found in the waste waters of a wide variety of industries that must be removed because of the danger they represent to human health. Among the major classes of contaminants, several aromatic molecules, including phenols and aromatic amines, have been reported. Enzymatic treatment has been proposed by many researchers as an alternative to conventional methods. In this respect, PX has the ability to coprecipitate certain difficult-to-remove contaminants by inducing the formation of mixed polymers that behave similarly to the polymeric products of easily removable contaminants. Thus, several types of PX, including HRP C, LiP, and a number of other PXs from different sources, have been used for treatment of aqueous aromatic contaminants and decolorization of dyes. Thus, LiP was shown to mineralize a variety of recalcitrant aromatic compounds and to oxidize a number of polycyclic aromatic and phenolic compounds. Furthermore, MnP and a microbial PX from Coprinus macrorhizus have also been observed to catalyze the oxidation of several monoaromatic phenols and aromatic dyes (Hamid and Khalil-ur-Rehman 2009). 

Anderson, R.S., J.E. Doos, and F.L. Rose. 1982. Differential ability of Ambystoma tigrinum hepatic microsomes to produce mutagenic metabolites from polycyclic aromatic hydrocarbons and aromatic amines. Cancer Lett. 16 33-41. 

Aliphatic amines are simple lone-pair n-donors, similarly to other n-donors like phosphines, ethers, alcohols, iodides etc. Aromatic amines may be both n- and rr-donors132. Typical rr-donors are polycyclic aromatic derivatives 7r-acceptors are polynitro aromatic derivatives, quinones etc. 

M.L. Tedjamulia. Y. Tominaga, M. Sugiura, H. Kudo, M.L. Lee u. R.N. Castle, Polynucl. Aromal. Hydrocarbons, Int. Symp., 7th, 1161-1172 (1982) The Synthesis of Potentially Mutagenic Polycyclic Aromatic Amines". 

Further study of the reaction has indicated that nitroanilines, as well as aminobenzoic acids, are not substantially converted into azo compounds, whereas polycyclic aromatic amines give polymeric products. 

Fortunately, there is now a comprehensive body of knowledge on the metabolic reactions that produce reactive (toxic) intermediates, so the drug designer can be aware of what might occur, and take steps to circumvent the possibility. Nelson (1982) has reviewed the classes and structures of drugs whose toxicities have been linked to metabolic activation. Problem classes include aromatic and some heteroaromatic nitro compounds (which may be reduced to a reactive toxin), and aromatic amines and their N-acylated derivatives (which may be oxidized, before or after hydrolysis, to a toxic hydroxylamine or iminoquinone). These are the most common classes, but others are hydrazines and acyl-hydrazines, haloalkanes, thiols and thioureas, quinones, many alkenes and alkynes, benzenoid aromatics, fused polycyclic aromatic compounds, and electron-rich heteroaromatics such as furans, thiophenes and pyrroles. 

TNT forms charge-transfer, or 7r, complexes with polycyclic aromatic hydrocarbons, aromatic amines, and aromatic nitro compds a number of these are listed below in Table 2. The complexes with three amines (diphenylamine, diethyl-aniline, p-anisidine) have characteristic colors this forms the basis for a rapid and convenient thin-layer chromatographic analytical procedure (Ref 34) for the identification of very small amounts of TNT. (For a discussion of the many color reactions of TNT, and of composite expls containing it, see Vol 3, C405-L ff)... 

Many polycyclic aromatic amines and aldehydes are commercially available, but their supply is very limited. Preparation of these starting materials is necessary for studying the (3-lactam formation reaction [93]. Nitro compounds are the precursors for the amines. An important task was to prepare polycyclic aromatic nitro compounds, particularly those of chrysene, phenanthrene, pyrene, and dibenzofluorene in good yield. Nitration of these hydrocarbons with concentrated nitric acid in sulfuric acid is a widely used reaction for this purpose. Our research culminated in facile synthesis of polyaromatic nitro derivative 9 starting from polyaromatic hydrocarbons (PAHs) 8 through the use of bismuth nitrate impregnated with clay (Scheme 1) ([94, 95] for some examples of bismuth nitrate-catalyzed reactions... 

The compounds of the particle phase are collectively called tar, or total particulate matter (TPM). Tar is the oily residue left behind when moisture evaporates from burned tobacco. It contains thousands of compounds, including cancer-causing aromatic amines, nitro-samines, and polycyclic aromatic hydrocarbons that are present in both smoking and smokeless tobacco. Other harmful constituents include radioactive lead and polonium as well as arsenic, among others. 

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