2-naphthylamine, role

Bagal et al. (1975) investigated in more detail the role of donor-acceptor complexes in the azo coupling reaction of the 4-nitrobenzenediazonium ion with 2-naphthylamine-3,6-disulfonic acid and that of the 4-chlorobenzenediazonium ion with 2-naphthol-6-sulfonic acid. Their kinetic results are, as would be expected, compatible with the mechanisms shown in Schemes 12-74 or 12-75. 

A marginal hydrogenation of the benzenic ring of 1-naphthylamine leading to 5,6,7,8-tetrahydro-l-naphthylamine [72] was explained as due to a weaker adsorption of the benzene part than of the aniline part of the naphthylamine. However, this reaction was disregarded for the HDN of 1-naphthylamine, as the minor role it could play under the studied conditions. 

The role of N-sulfonyloxy arylamines as ultimate carcinogens appears to be limited. For N-hydroxy-2-naphthylamine, conversion by rat hepatic sulfotransferase to a N-sulfonyloxy metabolite results primarily in decomposition to 2-amino-l-naphthol and 1-sulfonyloxy-2-naphthylamine which are also major urinary metabolites and reaction with added nucleophiles is very low, which suggests an overall detoxification process (9,17). However, for 4-aminoazobenzene and N-hydroxy-AAF, which are potent hepatocarcinogens in the newborn mouse, evidence has been presented that strongly implicates their N-sulfonyloxy arylamine esters as ultimate hepatocarcinogens in this species (10,104). This includes the inhibition of arylamine-DNA adduct formation and tumorigenesis by the sulfotransferase inhibitor pentachlorophenol, the reduced tumor incidence in brachymorphic mice that are deficient in PAPS biosynthesis (10,115), and the relatively low O-acetyltransferase activity of mouse liver for N-hydroxy-4-aminoazobenzene and N-OH-AF (7,114,115). 

Recently, Japaridze etal. [170] have investigated adsorption of some aromatic compounds, including naphthalene, naphthonitrile, naphthylamine, anthracene, and phenathrene at the mercury electrode I ethylene glycol solution interface. The analysis of the differential capacity data obtained at the HMDE has revealed that adsorption of the above-mentioned compounds obeys the Frumkin model, with attractive interactions of the particles in the adsorption layer. The results for ethylene glycol were compared with those for other nonaqueous solvents and their role in determining the adsorption mode was discussed. 

Case, R. A., Hosker, M. E., Me, D. D., and Pearson, J. T. (1954). Tumours of the urinary bladder in workmen engaged in the manufacture and use of certain dyestuff intermediates in the British chemical industry. I. The role of aniline, benzidine, alpha-naphthylamine, and beta-naphthylamine. Br J Ind Med 11, 75-104. 

Figure 7. Role of metabolism and sys temic transport in the formation of bladder tumors by 2-naphthylamine...

Proton-induced quenching often plays an important role in acid-base equilibrium in the excited state of aromatic molecules as described above. For the proton-induced quenching mechanism of naphthylamines, a complex in which a proton is shared between excited 2-naphthylamine and one water molecule [43] or a hydrated naphthylammonium cation in the ground state [44] was assumed as an intermediate... 

Tertiary amines are essentially physical quenchers of singlet oxygen however, chemical reaction, both type 1 and type II, may have a role and have in fact being observed with some electron-donating substituted dimethylanihnes. 2-Naphthylamine undergoes oxidative ring cleavage. 5... 

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