Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third...

Directly acting mutagens formed from N-nitroso-N-(formylmethyl)alkylamines (3) were isolated and identified as N-nitroso-N-alkyl-1-hydroxyimino-2-oxoethylamines (4). Their structures were elucidated on the basis of nuclear magnetic resonance spectra and confirmed by derivatization to the crystalline 2,4-dinitrophenylhydrazones (5). Compounds 4 (alkyl =ethyl and butyl) were strongly mutagenic to...

The support vector machine (SVM), as a novel type of learning machine, was used to develop a classification model of carcinogenic properties of 148 N-nitroso compounds. The seven descriptors calculated solely from the molecular structures of compounds selected by forward stepwise linear discriminant analysis (LDA) were used as inputs of the SVM model. The obtained results confirmed the discrimi...

The photochemistry of p-azidoaniline was studied in argon matrices in the absence and presence of oxygen. With the help of quantum chemical calculations we were able to characterize the triplet p-aminophenylnitrene as well as the cis- and trans-p-aminophenylnitroso oxides. It was found that the latter two isomers can be interconverted by selective irradiation and that they are ultimately conver...

A new viscometric technique, capable of detecting DNA strand breaks and alkali-labile sites by monitoring time-dependent changes of DNAreduced viscosity, has been used to analyze dose-response curves for the induction of DNA damage in liver of rats treated with single p.o. doses of sixteen A-nit roso compounds. Statistically significant changes of DNA viscometric parameters, which are considere...