A black-box approach to the construction of metal-radical multispin systems and analysis of their magnetic properties.

An interaction of M(hfac)2 (M = Mn or Ni) with N-(bis(4,4,5,5-tetramethyl-3-oxido-1-oxyl-4,5-dihydro-1H-imidazol-2-yl)methylene)-2-methyl-propan-2-amine oxide (a nitronyl nitroxide diradical with the >C[double bond, length as m-dash]N(O)-tert-Bu coupler) was investigated under various conditions. It was found that prolongation of reaction time caused transformation of the initial diradical into new diradicals with the unique >C[double bond, length as m-dash]N-OH coupling unit and formation of binuclear Mn(ii) and Ni(ii) complexes, which were characterized by X-ray diffraction analysis. The resulting binuclear heterospin complexes have a complicated magnetic structure with six paramagnetic centers and a number of exchange interaction channels between them, as well as between neighboring complexes. To adequately describe the magnetic properties of these complexes, high-level ab initio calculations of their electronic structure and parameters of the spin-Hamiltonian were carried out. The accuracy of the conventional broken-symmetry density functional theory approach in the calculation of the exchange interaction parameters was also verified.

[Discoveries of Giulio Cesare Aranzi]. / Otkrytiia Dzhulio Chezare Arantsi.

The article provides a Russian translation of the 19th chapter of the work of Italian anatomist and surgeon Giulio Cesare Aranzi (Julius Caesar Arantius, 1530-1589) 'Observationes anatomicae', which describes his discoveries in the anatomy of the organ of vision: detection of m. levator palpebrae superioris and disproving of the then prevailing statement concerning the origin of external muscles of the eye from the dura mater. The article also gives a brief biography.

Biomonitoring of selected persistent organic pollutants (PCDD/Fs, PCBs and PBDEs) in Finnish and Russian terrestrial and aquatic animal species.

BACKGROUND: The Finnish and Russian animal species (semi-domesticated reindeer, Finnish wild moose, Baltic grey seal and Baltic herring) samples were biomonitored in terrestrial and aquatic environments for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs). RESULTS: Grey seal (Halichoerus grypus) was clearly the most contaminated species. The mean PBDE concentration in grey seal was 115 ng/g fat, and the highest WHO-PCDD/F-PCB-TEQ (toxic equivalent set by WHO) was 327 pg/g fat. In Finnish, reindeer WHO-PCDD/F-TEQ varied from 0.92 pg/g fat in muscle to 90.8 pg/g fat in liver. WHO-PCDD/F-TEQ in moose liver samples was in the range of 0.7-4.26 pg/g fat, and WHO-PCB-TEQ in the range of 0.42-3.34 pg/g fat. Overall moose had clearly lower PCDD/F and DL-PCB concentrations in their liver than reindeer. CONCLUSIONS: Terrestrial animals generally had low POP concentrations, but in reindeer liver dioxin levels were quite high. All Finnish and Russian reindeer liver samples exceeded the EU maximum level [8] for PCDD/Fs (10 pg/g fat), which is currently set for bovine animals.

Structural specifics of light-induced metastable states in copper(II)-nitroxide molecular magnets.

Although light-induced magnetostructural switching in copper(II)-nitroxide molecular magnets Cu(hfac)2L(R) has been known for several years, structural characterization of metastable photoinduced states has not yet been accomplished due to significant technical demands. In this work we apply, for the first time, variable-temperature FTIR spectroscopy with photoexcitation to investigate the structural specifics of light-induced states in the Cu(hfac)2L(R) family represented by (i) Cu(hfac)2L(Me) comprising two-spin copper(II)-nitroxide clusters, and (ii) Cu(hfac)2L(Pr) comprising three-spin nitroxide-copper(II)-nitroxide clusters. The light-induced state of Cu(hfac)2L(Me) manifests the same set of vibrational bands as the corresponding thermally-induced state, implying their similar structures. For the second compound Cu(hfac)2L(Pr), the coordination environment of copper(II) is similar in light- and thermally-induced states, but distinct differences are found for packing of the peripheral n-propyl substituent of nitroxide. Thus, generally the structures of the corresponding thermally- and light-induced states in molecular magnets Cu(hfac)2L(R) might differ, and FTIR spectroscopy provides a useful approach for revealing and elucidating such differences.

Evaluation of magnetic resonance imaging characteristics of new nitroxyl radicals on the model of RLS lymphoma.

Toxic and magnetic resonance contrast characteristics of new nitroxyl radicals Fur-135 and Fur-176 were studied in experiments on mice. The test compounds exhibited low toxicity and allowed us to increase contrasting of transplanted RLS lymphoma. Fur-135 differs by the type of contrasting from Gd(3+)-containing preparation omniscan and locates the tumor focus with high precision.

Evidence for an aryl migration during the electron impact induced fragmentation of substituted aryloxymethylquinoxalines.

The electron impact (EI) mass spectra of 34 differently substituted 2-phenoxymethyl-, 2-naphthyloxymethyl-, 2-pyridinyloxymethyl- and 2-chinolinyloxymethylquinoxalines were recorded. The fragmentation patterns were examined by metastable ion analysis and exact mass measurements, employing finally also selective deuterium labelling. The inclusion of the substituted aryl ring moiety appears to be important for the fragmentation of the aryloxymethylquinoxalines. A molecular ion rearrangement is proposed for the observed loss of OH* and CHO* radicals. The influence of the different substituents on the aryl ring moiety on the rearrangement in the gas phase and on the resulting fragmentation was investigated.

Electron ionisation induced fragmentation of ethyl 5(1H)-oxo- and 7(1H)-oxo-1-aryl-2,3-dihydroimidazo[1,2-a]-pyrimidine-6-carboxylates: evidence for an unusually regioselective rearrangement of M(+*) ions.

The 70-eV electron ionisation (EI) mass spectra of the title compounds show clear differences between the 5-oxo and 7-oxo isomers due to regioselective fragmentations involving the ester function. Exceptionally abundant metastable peaks due to molecular ions fragmenting to [M -CO2](+.) were observed exclusively for the 7-oxo isomers, suggesting that the sufficiently long-lived molecular ions undergo a slow rearrangement preceding this fragmentation reaction. The results are contrasted to the available literature data on the ester group fragmentations involving the loss of CO2 and the EI mass spectrometry of pyrimidone beta-oxo esters. A reaction mechanism is proposed for the elimination of CO2 following ethyl group migration to the pyrimidone carbonyl oxygen.

5,5',6,6'-Tetrahydroxy-3,3'-biindolyl from beetroot (Beta vulgaris) peel extract.

A compound of unusual structure was isolated from red beetroot (Beta vulgaris) peel extract and identified as 5,5',6,6'-tetrahydroxy-3,3'-biindolyl based on the combination of NMR and MS studies.

Isolation and biological activity of frankiamide.

An antibiotic produced by the symbiotic actinomycete Frankia strain AiPs1 was isolated from culture broth using optimized thin-layer chromatography and high-performance liquid chromatography (HPLC) methods. The novel compound that was isolated, dubbed frankiamide, displayed antimicrobial activity against all 14 Gram-positive bacterial strains and six pathogenic fungal strains tested. The pathogenic actinomycete Clavibacter michiganensis and the oomycete Phytophthora were especially susceptible. In addition to displaying antimicrobial activity, frankiamide also strongly inhibited 45Ca(2+) fluxes in clonal rat pituitary GH4C1 tumor cells and was comparable to a frequently used calcium antagonist, verapamil hydrochloride. The results of HPLC analysis, supported by both nuclear magnetic resonance and mass spectroscopy studies, showed that frankiamide has a high affinity for Na(+) ions.

Nitronyl and imino nitroxides: improvement of Ullman's procedure and report on a new efficient synthetic route.

The synthesis of nitronyl and imino nitroxides has been reexamined with the aim of both increasing yields and of offering opportunities for new structures. The conditions for the formation of 2,3-bis(hydroxyamino)-2,3-dimethylbutane, the key intermediate of Ullman's route, have been carefully studied, and a new procedure is proposed, which affords the free base in a very pure form and up to 60% yield. Full characterization of this intermediate including an X-ray crystal structure is presented. An alternative synthetic route through 2,3-diamino-2,3-dimethylbutane and the corresponding imidazolidines which bypasses the delicate synthesis of the bis(hydroxyamino) compound is described. It is shown that 3-chloroperbenzoic acid is an effective oxidant for the transformation of adequately substituted imidazolidines into nitronyl nitroxides, which are obtained in high yield. An illustration of the potentialities of this new route, a new nitronyl nitroxide with two ethyl substituents in positions 4 and 5 of the imidazoline ring, is reported. The scope and limitations of the two routes are discussed.

Electron impact induced fragmentation of ( p-substituted phenyl)-(4'-methylphenacyl) sulfones: contribution of sulfinate ester rearrangements

The molecular ions of the title compounds are usually very unstable. The main fragmentation corresponds to the formation of p-MeC(6)H(4)CO(+) as would be expected. Another abundant fragment ion was [M - SO(2)](+) which is formed both from the original sulfone and from the rearranged sulfinate esters. There are, however, three primary ions which can be traced back to each isomeric molecular ion: p-RC(6)H(4)SO(2)(+) to the original sulfone, p-RC(6)H(4)SO(+) to the.CH(2)S(=O)O-. type sulfinate ester and p-RC(6)H(4)OH(+.) to the.CH(2)OS(=O). type sulfinate ester of which the latter seems by far to dominate. Copyright 2000 John Wiley & Sons, Ltd.

Chemical ionization mass spectra of acetals of beta-D-glycopyranosylnitromethanes

O-Isopropylidene and O-benzylidene acetals of common 2, 6-anhydro-1-deoxy-1-nitroalditols (beta-D-glycopyranosylnitromethanes) derived from D-glucose, D-galactose and D-mannose were studied by chemical ionization mass spectrometry (CIMS) using methane, isobutane, ammonia or pyridine as reaction gas. Production of [M+H](+) adduct ions dominates in the case of methane or isobutane possessing proton affinity values PA = 552 or 683 kJ mol(-1), respectively. The collision-induced dissociation time-of-flight product ion spectra of [M+H](+) ions differ characteristically according the stereochemical arrangement of the pyranoid ring. These differences can be helpful when assigning stereochemical arrangements for the pyranoid ring. The dominant process in ammonia (PA = 853 kJ mol(-1)) CIMS for most of the compounds studied is the production of the cluster ions [M+NH(4)](+). The cluster [M+pyridineH](+) ions are observable only for substances possessing the O-benzylidene group (PA of pyridine = 924 kJ mol(-1)). Copyright 2000 John Wiley & Sons, Ltd.

Electron ionization mass spectra of acetals of beta-D-glycopyranosylnitromethanes

O-Isopropylidene and O-benzylidene acetals of common 2, 6-anhydro-1-deoxy-1-nitroalditols (beta-D-glyco- pyranosylnitromethanes) derived from D-glucose, D-galactose and D-mannose were studied by electron ionization (EI) mass spectrometry. Fragment pathways of the title compounds were studied using accurate mass measurements, collision-induced dissociation, B/E and B2/E measurements of selected ions and mass spectra of O-deuterium-labelled compound. The fragmentation pathways and some differences found among the mass spectra of stereoisomers are discussed. Noteworthy is the splitting off of the (.)NO(2) radical and elimination of acetone from the molecular ions of 4, 6-O-benzylidene-2, 3-O-isopropylidene-beta-D-galactopyranosylnitromethane. This fragmentation route of relatively high abundance was not observed in the case of D-gluco and D-manno analogues. The differences in the EI mass spectra of stereoisomers may help to provide some information serving for the estimation of the stereochemical arrangement of compounds of this type. Copyright 1999 John Wiley & Sons, Ltd.

The history of Russian psychoanalysis and the problem of its periodisation.

The formation and spread of the psychoanalytic teaching of Sigmund Freud and his followers is one of the most significant events in the life of the spirit in the twentieth century. The recognition of this as an historical fact--irrespective of its relation to Freud and his ideas--assumes of course and need to gain a proper understanding and appropriate interpretation of psychoanalysis in all its dimensions. Generally speaking, the history of psychoanalysis and the psychoanalytic movement has been researched quite fully, although for a variety of reasons and circumstances there are a number of gaps in it. Perhaps the most important of these is the history of Russian psychoanalysis, which has developed within a country where, at the beginning of the century, Freud's works were translated and published in a most effective and representative way, and where psychoanalytic ideas drew a response both from specialists and among the public at large, although in content and inclination the Russian mentality did not at heart suit a psychoanalytical treatment of man and his culture.

Love, psychoanalysis and destruction.

The author presents the available information concerning the eminent Russian psychoanalyst Sabina Spielrein, who originally developed the idea of destruction. A major part of the article, which concerns today's popular following of C. G. Jung and S. Freud, is based on documents in the Russian (Moscow) archives, and touches upon the least known periods and facts of her tragic life and of her creative activity.

[Effectiveness of low-frequency ultrasound in the treatment of chronic tonsillitis]. / Analiz éffectivnosti lecheniia khronicheskogo tonzillita nizkochastotnym ultrazvukom.

500 patients with chronic tonsillitis (450 patients with toxicoallergic form I and 50 patients with toxico-allergic form II according to Palchun and Preobrazhensky) have been exposed to low-frequency ultrasound. Content of the tonsillar lacunae was extracted under vacuum, the lacunae were washed with antiseptic under the effect of ultrasound followed by introduction of the drugs into the tonsillar tissue (phonophoresis). The above method proved effective: 64% responded immediately, 56% of the patients sustained the effect at follow-up. Low-frequency ultrasound treatment should be supported with therapeutic measures to prevent development of autoimmune processes capable of provoking systemic complications. For patients who failed 3-4 courses of the ultrasound treatment surgery is indicated. Contraindications concern subjects suffering from toxico-allergic form II of chronic tonsillitis.

[Decarboxylation of amino acids and peptides in a photoreaction with potassium ferricyanide at 77 K]. / Dekarboksilirovanie aminokislot i peptidov v fotoreaktsii s ferritsianidom kaliia pri 77 K.

We have measured action spectra of formation of radicals in aliphatic amino acids and peptides by reaction of decarboxylation with excited potassium ferricyanide. Peptides are capable to the reaction under longwave absorbtion band excitation, whereas amino acids are stable under these conditions, and decarboxylation occur only under irradiations by lambda < 400 nm.