In the unit cell of the title compound, C(5)H(7)N(3)O, there are two conformers (A and B) which differ in the position of the oxime group with respect to the protonated pyrazole nitro-gen (trans in the A conformer and cis in the B conformer) and in the geometric parameters. The oxime group exists in the nitroso form in both conformers. In the crystal, mol-ecules are linked by inter-molecular N-...

BACKGROUND N-nitroso compounds (NOC) are found in processed meat and are formed endogenously from intake of nitrite and nitrate. Endogenous NOC formation is antagonized by nitrosation inhibitors in fruit and vegetables (e.g., vitamin C) and promoted by heme in red meat. It has been hypothesized that a diet resulting in high exposure to NOCs increases adult glioma risk. METHODS Using proportio...

The interaction of l-nitroso-2-naphthol and tyrosine to yield a red compound has long been used as a test for this amino acid in biological extracts. This reaction has been used for the quantitative determination of tyrosine (l-3), but it is not satisfactory because the red derivative is unstable. Further investigation of the reaction in this laboratory has shown that the red compound derived f...

Nitrosamines, or more precisely N-nitrosamines, along with N-nitrosamides, belongs to N-nitroso compounds, a class of organic compounds that have nitroso (-N=O) group attached directly nitrogen atom. Only few them occur naturally while the majority is formed by nitrosation secondary amines in living and working environment, food, tobacco smoke, etc. These scarce application industry, but they c...

The mutant 572-403 of Bacillus brevis Vm4 was isolated from N-methyl-N'-nitro-N-nitroso guanidine (nitrosoguanidine)-treated cultures of the parental strain. The mutant produces tatumine and edeine B when grown in a defined medium at 40 degrees C. Tatumine is composed of spermidine, glycine, isoserine, and an unidentified ninhydrin-positive compound; it has a molecular weight of less than 730 d...

N-nitroso compounds represent a common type of environmental and endogenous DNA-damaging agents. After metabolic activation, many N-nitroso compounds are converted into a diazoacetate intermediate that can react with nucleobases to give carboxymethylated DNA adducts such as N3-carboxymethylthymidine (N3-CMdT) and O(4)-carboxymethylthymidine (O(4)-CMdT). In this study, we constructed non-replica...

A hydrophilic hetero-Diels-Alder cycloadduct was synthesized as a novel photocontrollable donor of reactive nitrogen species. Production of either nitric oxide (NO) or nitroxyl (HNO) was photoinduced from this compound, depending on the environmental polarity.

Inactivation of the human DNA repair protein, O6-alkylguanine-DNA-alkyltransferase (AGT), by exposure to O6-benzylguanine leads to a dramatic enhancement in the cytotoxic response of cells to chemotherapeutic alkylnitrosoureas. Benzylated pyrimidines identified as more potent inactivators than O6-benzylguanine in vitro include 2,4-diamino-6-benzyloxy-5-nitrosopyrimidine (5-nitroso-BP) and 2,4-d...