Application of N-Nitrosamines

Although N-methyl-N-nitrosourea can induce cancer in human beings, its derivatives were found to be potent antitumor agents. l,3-Bis(2-chloroethyl)-l-nitrosourea (BCNU), l-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea (CCNU) and l-(2-chloroethyl)-3-(2,6-dioxo-3-piperidyl-l-nitrosourea (PCNU) l-(2-Choroethyl)-3-(4-methylcyclo-hexyl)-l-nitrosourea and l-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea showed antitumor activity by alkylating with DNA [82-84]. N-Nitrosourea-based prodrugs designed to become activated by tumor-associated proteases were found to provide enhanced 

N-Nitrosamines have been shown to be inhibitors of cysteine-containing enzymes. For example, dephostatin and other N-methyl-N-nitrosoanilines (1) were found to be inhibitors of the protein tyrosin phosphatases, papain and caspase [90,91]. Inhibition results from the S-nitrosation of the critical cysteine residues in the active sites of the enzymes by the nitrosamines. Compounds 6 and 7 have been found to inhibit thrombus formation in arterioles and venules of rats [92], while N-nitrosamide 9 exhibited vasodilation and mutagenicity as a result of NO release [93]. 

N-Nitroso-N-cyclohexylhydroxylamine is a synergistic agent for insecticides [94] it increases the insecticidal activity ofchlordane. Certain N-alkylphenylnitrosamines [95] and alkyl N-alkyl-N-nitrosocarbamates [96] are insecticides and fungicides, and may also be used for the impregnation of fabrics, etc. They have larvicidal action against Drosophila melanogaster and can also kill all moth larvae and weevils. 

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