7, 12-Dimethylbenz anthracene

Plates, leaflets from acetone-alcohol faint greenish-yellow tinge mp, 122 123°C.1 

Freely soluble in benzene, moderately soluble in acetone, slightly soluble in alcohol insoluble in water may be solubilized in water by purines.1 

One of the most potent carcinogenic polycyclic aromatic hydrocarbons. In animals, large single and multiple doses produce tumors of the skin, breast, and stomach or leukemias, regardless of route of administration. It is a strong mutagen after metabolic activation.2-4 

Wear goggles and protective gloves and clothing. Turn off the ventilation and isolate the spill area. Add enough dimethylformamide to completely wet the contaminated surface, and then pour over the area an excess of a freshly prepared solution of 4.7 g of potassium permanganate in 3 M sulfuric acid (17 mL of concentrated sulfuric acid slowly added to 83 mL of cold water). Allow to react for at least 1 hour. Absorb the residual solution on a 1 1 1 mixture by weight of soda ash, clay cat litter (bentonite), and sand. Scoop the mixture into a container and, in the fume hood, slowly add it to a beaker of cold water. If necessary, neutralize the solution with soda ash. Decant or filter the liquid into the drain with water. Discard the solid as normal refuse.5,6 

Package Lots. Place in a separate labeled container for disposal by burning. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with afterburner and scrubber.7 

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Evarts RP, Brown CA Atta GJ The effects of hydroxylamine on the morphology of the rat mammary gland and on the induction of mammary tumors by 7,12-dimethylbenz( )anthracene. Exp Mol Pathol 30 337-348, 1979... 

The numbering in the final molecule can be different from the one used in the original compound, since the addition of more rings may change its orientation in the frame of reference. For example, consider anthracene (VIII), 9,10-dimethylanthracene (IX), and 7,12-dimethylbenz[ ]anthracene (X) ... 

Fluorine bonded to higher condensed ring systems can also be replaced. Thus, 5-fluoro-3-mcth-oxy-7,12-dimethylbenz[ ]anthracene reacts with the sodium salt of ethanethiol in dimethyl-formamidc (155°C, 3 h) to yield 5-(eLhylsull anyl)-3-hydroxy-7,12-dimethylbcnz[ ]anthraccnc (58% mp 118-121 °C).y... 

As mentioned earlier that sesame lignans, especially sesamin and epi-sesamin, could influence the metabolism of polyunsaturated fatty acid and the production of prostaglandins. As prostaglandin is one of the most influential factors for mammary carcinogenesis, Hirose et al. (99) studied the effect of sesamin on dimethylbenz-anthracene (DMBA)-induced mammary cancer. Their results showed that sesamin at a dietary level of 0.2% considerably reduced the cumulative number and mean number of mammary cancer the effectiveness of sesamin was similar to a-tocopherol. 

Yu, Q. and Degregorio, M.W. (2005) Ospemifene inhibits the growth of dimethylbenz anthracene-induced mammary tumors in Senear mice. The Journal of Steroid Biochemistry and Molecular Biology, 97, 230-240. 

Singletary, K.W., and J.M. Nelshojjpen. 1991. Inhibition of 7,12-dimethylbenz[ ]anthracene (DMBA)-induced mammary tumorigenesis and of in vivo formation of mammary DMBA-DNA adducts by rosemary extract. Cancer Lett. 60(2) 169-175. 

A stmcturally related series of phenyfiiydrazones resulted ia the selection of compound A-007 [2675-35-6] (DEKK-TEC)(37) for the treatment of hormone-dependent tumors. A-007 is an antiestrogen that, ia contrast to tamoxifen, demonstrated inhibitory activity both ia the presence and absence of estradiol ia ZR-75-1 estrogen-dependent human breast cancer cells, and afforded more protection than tamoxifen ia the 7,12-dimethylbenz[i7]anthracene... 

Dimethylbenz[from acetone/EtOH. 

Diethyl aniline, 54 Diethylcarbaniazine citrate, 54 Diethyl carbamyl chloride, 54 Diethyl chlorophosphate, 54 Diethylene triamine, 54 Diethyl ether, 54 Di(2-ethylhexyl) phthalate, 54 Diethyl ketone, 54 Diethyl-p-phenylenediamine, 54 Diethyl phthalate, 54 Diethylstilbestrol, 55 Diethyl sulfate, 55 Diethyl zinc, 55 Difluoromethane chloride, 55 Digitoxin, 55 Diglycidyl ether, 55 Digoxin, 55 Diisobutyl ketone, 55 Diisopropylamine, 55 Diisopropyl ether, 55 DIKAMIN , 2,4-D, 55 DIKONIRT , 2,4-D, 55 Dimefox, 55 Dimethoate, 55 3,3 -Dimethoxybenzidine, 55 n,n-Dimethylacetamide, 56 Dimethylamine, 56 4-Dimethylaminoazobenzene, 56 Dimethylaminoethanol, 56 n,n-Dimethyl aniline, 56 7,12-Dimethylbenz[a]anthracene, 56 3,3 -Dimethylbenzidine, 56... 

Two types of reactions are important in the photochemical transformation of PAHs, those with molecnlar oxygen and those involving cyclization. lllnstrative examples are provided by the photooxidation of 7,12-dimethylbenz[a]anthracene (Lee and Harvey 1986) (Fignre 1.14a) and benzo[a]pyrene (Lee-Ruff et al. 1986) (Figure 1.14b), and the cyclization of CM-stilbene (Figure 1.14c). 

Bhuvaneswari, V., B. Velmurugan, S. Balasenthil, C. R. Ramachandran, and S. Nagini. 2001. Chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a] anthracene-induced hamster buccal pouch carcinogenesis. Fitoterapia 72(8) 865-874. 

Research in PAH carcinogenesis has made major advances in the past decade. Most notable has been identification of diol epoxide metabolites as the active forms of benzo[a]pyrene, 7,12-dimethylbenz[tf]anthracene, and other carcinogenic PAH. This finding has stimulated enormous research activity and opened the way to determination of the detailed molecular mechanism of action of this important class of carcinogenic molecules. 

For example, 7,12-dimethylbenz[a]anthracene is a particularly potent carcinogen for the mammary gland of young female Sprague-Dawley rats after oral or intravenous administration (25,26), dietary benzo[a]pyrene leads to leukemia, lung adenoma and stomach tumors in mice (27), and either of these hydrocarbons can induce hepatomas in male mice when injected on the first day of life (28). Nevertheless, the mouse skin system has proved to be particularly valuable because of the rapidity of tumor induction, the ease of detection of tumors and because the multi-stage nature of the carcinogenic process was experimentally established in this system. 

Similarly, the potent activity of 7,12-dimethylbenz[aj-anthracene can be destroyed by the presence of methyl groups on the 2-or 3- positions but the 4-methyl derivative remains active. 

Methods for the synthesis of the biologically active dihydrodiol and diol epoxide metabolites of both carcinogenic and noncarcinogenic polycyclic aromatic hydrocarbons are reviewed. Four general synthetic routes to the trans-dihydrodiol precursors of the bay region anti and syn diol epoxide derivatives have been developed. Syntheses of the oxidized metabolites of the following hydrocarbons via these methods are described benzo(a)pyrene, benz(a)anthracene, benzo-(e)pyrene, dibenz(a,h)anthracene, triphenylene, phen-anthrene, anthracene, chrysene, benzo(c)phenanthrene, dibenzo(a,i)pyrene, dibenzo(a,h)pyrene, 7-methyl-benz(a)anthracene, 7,12-dimethylbenz(a)anthracene, 3-methylcholanthrene, 5-methylchrysene, fluoranthene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)-fluoranthene, and dibenzo(a,e)fluoranthene. 

Although benz(a)anthracene (BA) is generally considered noncarcino-genic (27), it is a weak tumor initiator when administered with a phorbol ester promoter (28). More importantly, BA is a convenient model for the highly potent carcinogenic PAH 7,12-dimethylbenz(a)-anthracene and 3-methylcholanthrene (27), both of which are BA derivatives but which offer more serious synthetic problems. 

Human exposure to complex mixtures of polycyclic aromatic hydrocarbons (PAH) occurs through inhalation of tobacco smoke and polluted indoor or outdoor air, through ingestion of certain foods and polluted water, and by dermal contact with soots, tars, and oils CO. Methylated PAH are always components of these mixtures and in some cases, as in tobacco smoke and in emissions from certain fuel processes, their concentrations can be in the same range as some unsubstituted PAH. The estimated emission of methylated PAH from mobile sources in the U.S. in 1979 was approximately 1700 metric tons (2). The occurrence of methylated and unsubstituted PAH has been recently reviewed (1, 2). In addition to their environmental occurrence, methylated PAH are among the most important model compounds in experimental carcinogenesis. 7,12-Dimethylbenz[a]anthracene, one of... 

The Intercalation of Benzo[a]pyrene and 7,12-Dimethylbenz[a]anthracene Metabolites and Metabolite Model Compounds into DNA... 

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