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Nitrosoureas carcinogenicity

H2NCON(NO)Me, KOH, DME, H2O, 0°, 75% yield. This method generates diazomethane in situ. A -Methyl-A -nitrosourea is a proven carcinogen. [Pg.231]

Chloroethyl)-3-cyclohexyl-l-nitrosourea (CCNU) [13010-47-4] (Vol. 26, Suppl. 7 1 (NB Overall evaluation upgraded from 2B to 2A with supporting evidence from other carcinogenicity and its mechanisms)... [Pg.98]

This far into a nitrosamine symposium it should hardly be necessary to point out that nitrosamines are technically just one of a group of Ji-nitroso compounds that also includes nitros-amides, nitrosocarbamates, nitrosoureas, etc. Or that nitrosa-table pesticides encompass all the categories just mentioned and more. Or that many diverse pesticides, including herbicides, insecticides, and fungicides have been converted to Ji-nitroso derivatives in the laboratory (a recent review contained a 3-page, probably incomplete, compilation), or that some of the Ji-nitroso compounds thus synthesized were determined to be carcinogenic in test animals or mutagenic in various assays. [Pg.349]

Carbamate esters of zinc, zineb, and ziram are carcinogenic and teratogenic in animals, but this is attributed to the action of the carbamate esters and not to zinc (Elinder 1986). Results of studies with small mammals showed zinc to be cocarcinogenic with 4-nitroquinoline-N-oxide on oral cancer, and with N-ethyl-N-nitrosourea on brain cancer (Leonard and Gerber 1989). [Pg.646]

Warren, W, Clark, J.P, Gardner, E., Harris, G, Cooper, C.S. Lawley, PD. (1990) Chemical induction of thymomas in AKR mice interaction of chemical carcinogens and endogenous murine leukemia viruses. Comparison of W-methyl-A-nitrosourea and methyl methane-sulphonate. Mol. Carcinog., 3, 126-133... [Pg.1078]

N-Ethyl-N-nitrosourea is one of the most potent carcinogens known.773 774 These compounds, as well as diazomethane and other related substances, probably act via a common intermediate CH3N2+ or C2H5N2+.775... [Pg.1587]

The inhibitory effect of sitosterol (33) on colon tumor formation in rats treated with the carcinogen A-methyl-A-nitrosourea (MNU) has been studied, and it has been demonstrated that compound 33 nullified in part the effect of this direct-acting carcinogen on the colon [44]. This suggested that phytosterols may have a protective dietary action to retard colon tumor formation. [Pg.65]

The NH acidities of some sterically hindered ureas, namely the ureido esters (93), have been reported.81 The kinetics and mechanism of the alkaline hydrolysis of urea and sodium cyanate, NaCNO, have been studied at a number of temperatures.82 Urea hydrolysis follows an irreversible first-order consecutive reaction path. Tetrahedral intermediates are not involved and an elimination-addition mechanism operates. Sodium cyanate follows irreversible pseudo-first-order kinetics. The decomposition of the carcinogen /V-mcthyl-/V-nitrosourea (19) was dealt with earlier.19 The pyrolysis of (V-acetylurea goes by a unimolecular first-order elimination reaction.83... [Pg.51]

CLA was effective for both the direct-acting carcinogen methyl-nitrosourea (MNU) and the indirect-acting DMBA, suggesting the action of CLA was independent of carcinogen activation. [Pg.619]

See other pages where Nitrosoureas carcinogenicity is mentioned: [Pg.109]    [Pg.435]    [Pg.55]    [Pg.56]    [Pg.162]    [Pg.8]    [Pg.10]    [Pg.144]    [Pg.56]    [Pg.63]    [Pg.316]    [Pg.642]    [Pg.101]    [Pg.102]    [Pg.104]    [Pg.227]    [Pg.394]    [Pg.395]    [Pg.169]    [Pg.385]    [Pg.437]    [Pg.1071]    [Pg.41]    [Pg.336]    [Pg.74]    [Pg.125]    [Pg.820]    [Pg.550]    [Pg.55]    [Pg.56]    [Pg.165]    [Pg.41]    [Pg.440]   
See also in sourсe #XX -- [ Pg.41 ]

See also in sourсe #XX -- [ Pg.41 ]

See also in sourсe #XX -- [ Pg.41 ]



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Nitrosoureas

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