Nitrosamine methyl-

Dimethylhydrazine Di methyl nitrosamine bis (Dimethylthiocarbamoyl) disulphide Dinitrobenzene (all isomers)... 

Chung, F.L. and Xu, Y. (1992). Increased 8-oxodeoxyguanosine levels in lung DNA of A/J mice and F344 rats treated with the tobacco-specific nitrosamine 4-(methyl-nitrosamine)-l-(3-pyridyl)-l-butanone. Carcinogenesis 13, 1269-1272. 

ACETOXYMETHYL-N-METHYL-NITROSAMINE 1-ACETOXY-N-NITROSODIMETH-YLAMNE AMMN ANN (GERMAN) DMN-OAC ALAMN METHYL-(ACETOXYMETHYL)NITRO-SAMINE N-NITROSO-.N-(ACETOXY)METHYL-N-METHYL,Ai nNE N-NTTROSO-N-METHYL-N-ACETOXYMETHYLAMNE... 

Nitrosamine and para Nitroso Methyl Aniline.—The reaction with nitrous acid is characteristic of secondary amines and yields phenyl methyl nitrosamine, the nitroso group entering the amino radical. This, however, undergoes rearrangement with the transference of the nitroso group to the ring yielding a nitroso benzene compound. 

The rearrangement occurs also when nitro benzene is electrolytically reduced by immersing the cathode in nitro benzene and sulphuric acid and the anode in sulphuric acid. Phenyl hydroxyl amine is first produced and by the above rearrangement is converted into para amino phenol. This rearrangement is analogous to the one occurring when phenyl methyl nitrosamine goes over to para-nitroso methyl aniline (P- S59)-... 

Trinitro-3-di methy laminopheny I-methyl-nitrosamine, (H3C)2N.CgH(N02)8-N(N0).CH3 mw 314.22, N 26.75% yel crysts, mp 132° prepd by reacting a warm glac acet acid soln of N,N,N, N -tettanitro-m-phenylenediamine with nitric acid (Refs 2 3)... 

The organozinc derivative of the bromoacetamide BrCH2CONMe2 can be metallated with PhsMCl (M=Si, Ge, or Sn) and the tin compound subsequently cleaved by TaClg. A-Methyl nitrosamines can be readily stannylated [equation (14)], the derivative adding to aromatic aldehydes to give stannyl ethers. ... 

Thiuram Sulfides. These compounds, (8) and (9), are an important class of accelerator. Thiurams are produced by the oxidation of sodium dithiocarbamates. The di- and polysulfides can donate one or more atoms of sulfur from their molecular stmcture for vulcanization. The use of these compounds at relatively high levels with litde or no elemental sulfur provides articles with improved heat resistance. The short-chain (methyl and ethyl) thiurams and dithiocarbamates ate priced 2/kg. Producers have introduced ultra-accelerators based on longer-chain and branched-chain amines that are less volatile and less toxic. This development is also motivated by a desire to rninirnize airborne nitrosamines. 

In saurer Losung wird Methyl-phenyl-nitrosamin an Blei zu N-Methyl-N-phenyl-hydra-zin reduziert (80% d.Th.)4. Analog verhalten sich Dialkyl-nitrosamine ( — 0,9 V, bis 82% d.Th.) in alkoholischer Salzsaure5. Zur Hcrstellung von N,N-Dimethyl-hydrazin aus dem N-Nitroso-Derivat s.ds. Handb., Bd. X/2, S. 42 (zuN,N-Dialkyl-hydrazinen s.Lit.6). 

Although the o-hydroxylation hypothesis has been given considerable support, it is clear that nitrosamines with alkyl side chains longer than methyl present additional possibilities for biological activation. It was stated earlier that even the o-hydroxylation hypothesis is based on considerable circumstantial evidence. This means that the other possible pathways are even more speculative, and hence, much more research needs to be carried out before some of the ideas advanced below will gain acceptance, or be put to rest. 

It is known that nitrosamines with side-chains longer than methyl are metabolically hydroxylated on virtually every carbon. For example, the urinary metabolites in the rat of di-n-butylnitrosamine include the glucuronides of the following hydroxylated nitrosamines (42). 

In this particular instance, u) and m-l hydroxylation, which is then followed by further oxidation and chain degradation, are the principal reactions ( ) In the case of di-n-pro-pylnitrosamine both a- and 3-oxidation occur, with the latter being about 15% of the former (44) The a-hydroxy lation leads to the formation of the n-propyldiazonium ion (22), while the 3-hydroxylation results, at least in part, in oxidation to N-propyl-N-(2-oxopropyl)nitrosamine. Krdger and Bertrum (45) suggested that this product can be cleaved to methyl-... 

We have found that the chemical sulfation of N-methyl-N-(2-hydroxyethyl)nitrosamine resulted in the direct formation of the oxadiazolium ion. 

In contrast, little is known about the DNA adducts formed from cyclic nitrosamines. Early studies indicated methylation of DNA by certain cyclic nitrosamines but these were not confirmed (25, 71, 72). Adducts from NPYR and NMOR have been detected but remain mostly uncharacterized (25, 61). The nature of the... 

Among the agricultural chemicals used for the cultivation of tobacco crops we find several amines, amides and carbamates. These include dimethyldodecylamine acetate (Penar), maleic hydra-zide-diethanolamine (MH-30), and carbaryl (Sevin) as a representative of the methyl urethanes (Figure 3 , 14), It is known that small quantities of these agents are found as residues in harvested tobacco (15). To date, only diethanolamine (DELA), the water-solubilizer for maleic hydrazide in MH-30, has been studied as a possible precursor for nitrosamines in tobacco and in tobacco smoke. In 1976, more than 1,400 metric tons of maleic hydrazide had been used on U.S. tobacco (16), most of which had been applied as the MH-30 formulation with diethanolamine (14,16). 

Brononol (2-Bromo-2-nitropropane-1,3-diol) in combination with methyl and propyl paraben. The paper generated by the Danish group (ref. 5 Knoll BASF publication) shows that the mechanism of action of Bronopol is independent of formaldehyde formation. The inclusion of Tetrasodium EDTA at about 0.02% to remove ions in the water or extracts and carefully excluding any tertiary amines such as triethanolamine to counteract the fears of the marketers with reference to possible nitrosamine formation and release of formaldehyde. The pH used is usually at 6 and below. 

Conversion of a nontoxic molecule to one that is toxic, or a molecule with low potency to one that is more potent. Examples include the formation of the phenoxy herbicide 2,4-D from the corresponding butyrate, formation of nitrosamines, and methylation of arsenicals to trimethylarsine. 

N-Nitroso compounds occur in many operations in the rubber industry. Some nitrosamines (nitrosodiphenylamine, N-N-dinitrosopentamethylenetetramine, polymerized N-nitroso 2,2,4-trimethyl-l,2-dihydroquinoline and N-methyl-N-4-dinitroso aniline) are used as organic accelerators and antioxidants in the production of rubber and often the products are found to be contaminated with such compounds [19]. 

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