Electronic structure and models of monooxygenase inductor receptor from a number of polychlorinated polycyclic compounds. 5. MNDO calculations of halogen derivatives of azoxybenzenes

The MNDO method has been used to calculate the electronic and geometric structure of 3,3,4,4-tetraehloroazoxybenzene (TCAOB), 3,3,4,4-tetrachloro-6-hydroxyazobenzene (TCHAB), and 2,3,7,8-tetrachlorodibenzofuran (TCDF). The TCAOB exists in the gas phase in the form of two configurations, one nonplanar and one nearly planar. The latter is approximately 4 kcal/mole less stable than the first. The oxidation of 3,3,4,4-tetrachloroazobenzene (TCAB) to TCAOB is endothermic only in the case of the acton of hydrogen peroxide, not molecular oxygen. The isomerization of TCAOB to TCHAB proceeds with a gain in energy (–62 kcal/mole); however, the reaction from the ground state of the TCAOB molecule is symmetry-forbidden and is possible only from an excited state of the TCAOB. The process of oxidation of TCAOB and TCHAB by molecular oxygen to form TCDF or 2,3,7,8-tetrachlorobenzo-p-dioxin is energy-favorable; this is important in judging the biological action of TCAOB.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 101–105, January, 1991.     

Synthesis of α-(4-hydroxyphenyl)-β,β,β-trifluoro-α-alanine derivatives

2,6-Dimethyl- and 2,6-dimethoxy-α-methoxycarbonyl-α-trifluoromethyl-p-methylenequinones have been synthesized. These compounds easily react with ammonia, morpholine, andp-toluidine to afford the corresponding α-(4-hydroxyphenyl)-β,β,β-trifluoro-α-alanine derivatives.     

α-Methoxycarbonyl-containing polyflouoalkylsulfenyl chlorides

New -methoxycarbon-containingy polyflnoroalkylsulfenyl chlorides were obtained. Reactions of sulfenyl chlorides containing primary, secondary and tertiary -methoxycarbonyl polyfluoroalkyl groups at the sulfur atom with some unsaturated, carbonyl, arromatic, and heteroaromatic compounds were studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya No 7. pp 1745–1752. July, 1996.     

Simultaneous Determination of Diethylstilbestrol, Testosterone, and 17β-Estradiol Residues in Meat and Meat Products Using Gas–Liquid Chromatography

A gas-chromatographic procedure was developed for the simultaneous determination of hormones (diethylstilbestrol, testosterone, and 17-estradiol) as heptafluorobutyric anhydride derivatives. A mid-polarity HP-50 capillary column (silicone liquid phase containing 50% phenyl groups) and an electron-capture detector were used. The detection limits were 0.3–0.6 mg in a sample of 2 L. The applicability of this procedure for the determination of hormone residues in meat and meat products was demonstrated.     

Preparation of substituted 3-hydroxy-3-trifluoromethyl-2(3H)benzofuranones

Conclusions When heated with methyl trifluoropyruvate in aprotic solvents and acetic acid above 120°C it was found that phenols (not containing electron acceptor ring substituents) regioselectively formed ortho-C-alkylation products which could be lactonized to 3-hydroxy-3-trifluoromethyl-2(3H)benzo[b]furanones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2511–2517, November, 1987.     

A new reaction of adenine and adenosine

Conclusions A new reaction of adenine and adenosine with hexafluoroacetone, affecting the amidine fragment of their molecules and leading to tricyclic 2, 2,9,9-tetrakis(trifluoromethyl)[1,3, 5]oxadiazine[3,4-i]purines, was conducted.Translated from Izvestiya Akademii Nauk SSSR, No. 11, pp. 2554–2557, November, 1985.     

Biodegradation of aromatic compounds by the yeast-like fungus Trichosporon cutaneum

The biodegradation reactions of veratryl- and guaiacylpropane compounds modeling structural fragments of the lignin macromolecule by the yeast-like fungusTrichosporon cutaneum D-46 have been investigated. It has been shown that the enzyme complex ofT. cutaneum is capable of catalyzing a series of reactions of the biotransformation of arylpropane substrates, namely: oxidation, the cleavage of the C_α-C_β bond of the propane chain, demethylation, and decarboxylation. The action of the enzymes was shown most actively in the case of substrates having an unsubstituted phenolic hydroxy group. Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk. Institute of Microbiology, Belorussian Academy of Sciences, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 558–564, September–October, 1992.     

Biodegradation of aromatic compounds by the yeast-like fungus Trichosporon cutaneum

The biodegradation reactions of veratryl- and guaiacylpropane compounds modeling structural fragments of the lignin macromolecule by the yeast-like fungusTrichosporon cutaneum D-46 have been investigated. It has been shown that the enzyme complex ofT. cutaneum is capable of catalyzing a series of reactions of the biotransformation of arylpropane substrates, namely: oxidation, the cleavage of the C-C bond of the propane chain, demethylation, and decarboxylation. The action of the enzymes was shown most actively in the case of substrates having an unsubstituted phenolic hydroxy group.Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk. Institute of Microbiology, Belorussian Academy of Sciences, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 558–564, September–October, 1992.     

Trifluoromethyl-p-tolyldiazomethane in 1,3-dipolar cycloaddition reactions

Trifluoromethyl-p-tolyldiazomethane (I) forms [3+2]-cycloadducts with activated alkenes and alkynes. The products of these regiospecific reactions are substituted pyrazolines (II)–(VI) and pyrazoles (VIII)–(X). Reaction of (I) with fumarates, trifluoropyruvates and allyl chloride is accompanied by elimination of N₂ and formation of a 1,2-bis(trifluoromethyl)stilbene. The results obtained indicate that (I) enters only the HOMO-controlled 1,3-dipolar addition reactions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1589–1593, July, 1991.