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11.
ValeryN. Kalinin IgorV. Shishkov SergeyK. Moiseev ElviraE. Shults GenrikhA. Tolstikov NataliaI. Sosnina PavelV. Petrovskii KonstantinA. Lyssenko Helmut Schmidhammer 《Helvetica chimica acta》2006,89(5):861-869
In a search for starting materials for the preparation of 7,8‐fused morphine alkaloid derivatives, 8‐[(1E‐2‐phenylethenyl]codeinone dimethyl ketal ( 4 ) and 8‐[(1E‐2‐phenylethenyl]codeine ( 5 ) were prepared. These dienes were used as substrates in the Diels–Alder reactions. Compound 5 formed the ‘normal’ adduct 12 with N‐phenylmaleimide, while compound 4 behaved in reactions with dienophiles as the ‘masked’ diene 11 , a 8‐[(1E)‐2‐phenylethenyl]‐substituted thebaine, yielding the corresponding 19‐substituted 6,14‐endo‐etheno‐6,7,8,14‐tetrahydrothebaines. Specifically, reaction of 4 with methyl vinyl ketone gave rise to 19‐[(1E)‐phenylethenyl]thevinone ( 14 ) whose structure was elucidated by an X‐ray diffraction analysis. The thebaine derivative 11 was also prepared from 4 . 相似文献
12.
13.
Guan-Sheng JiaoAurore Loudet Hong Boon LeeStanislav Kalinin Lennart B.-Å JohanssonKevin Burgess 《Tetrahedron》2003,59(17):3109-3116
The purpose of this project was to prepare fluorescent dyes that could absorb energy at relatively short wavelengths, and fluoresce in the near-IR region. To achieve this, copper- and palladium-mediated C-N couplings were used to prepare the ‘cassettes’, i.e the carbazole derivative 3b and the carbazole-, phenothiazine-, and phenoazine-squaraines 4b-d. These compounds have carbazole, phenothiazine, and phenoazine donor-components that absorb around about 300-320 nm, and squaraine acceptor-parts that fluoresce in the range 650-700 nm. The efficiencies of energy transfer from the donor to the acceptor, and the overall quantum yields of the cassettes were determined. 相似文献
14.
V. A. Mamedov A. A. Kalinin V. V. Yanilkin N. V. Nastapova V. I. Morozov A. A. Balandina A. T. Gubaidullin O. G. Isaikina A. V. Chernova Sh. K. Latypov I. A. Litvinov 《Russian Chemical Bulletin》2007,56(10):2060-2073
The oxidative dehydrocyclization of the 3-(indolizin-2′-yl)-2-oxoquinoxaline monopodand performed either electrochemically
or under the action of molecular iodine affords new redox-active heterocyclophane consisting of the redox-switchable biindolizine
fragment combined with the polyether-bridged π-deficient quinoxaline systems. The single-crystal X-ray diffraction study showed
that the trioxaundecane chain of heterocyclophane adopts an extended conformation, and one of the phenyl substituents of the
molecule closes the pseudocavity formed by the spacer from one of the sides. The cyclic voltammetric study of heterocyclophane
in MeCN and DMF showed the three-step oxidation of the indolizine fragments accompanied by the single-electron transfer in
each step. The first and third steps are reversible, and the second step is irreversible. The oxidation at potentials of the
first peak gives rise to stable radical cations detected by the ESR method (g = 2.0024, a
2N = 0.26 mT).
Dedicated to Professor E. A. Berdnikov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1991–2003, October, 2007. 相似文献
15.
M. V. Antonova S. K. Moiseev V. N. Kalinin I. O. Shapiro 《Russian Chemical Bulletin》1989,38(11):2256-2259
Kinetic acidities of aryl and benzyl CH-bonds for complexes of benzene and its methoxy and alkyl derivatives with tricarbonylchromium are determined in a solution of lithium tert-butoxide in N,N-dimethylacetamide. Complexation of alkyl-aromatic compounds to the Cr(CO)3 group increases the lability of the aryl CH-bond by 107–109 times and that of the benzyl bond by 5·104–5·105 times. The Cr(CO)3 group in arene complexes neutralizes the effect of other substituents regardless of their nature and position in the molecule.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2458–2461, November, 1989. 相似文献
16.
Highly efficient kinetic resolution of racemic secondary alkyl diazoacetates in intramolecular carbon-hydrogen insertion reactions has been achieved using chiral dirhodium(ii) carboxamidates. Products formed from catalytic diazo decomposition of racemic 2-octyl diazoacetate and, separately, its (2R)- and (2S)-enantiomeric forms, as well as bothcis- andtrans-2-methylcyclohexyl diazoacetates, have been systematically evaluated. Enantioselectivities up to 99 %ee have been obtained for -lactone formation. -Lactone production has been observed and, although minor with cyclohexyl diazoacetates, is the major insertion pathway for diazo decomposition of 2-octyl diazoacetate.Dedicated to Academician of the RAS N. S. Zefirov (on his 60th birthday).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1798–1803, September, 1995.Financial support for this research from the National Institutes of Health (GM 46503) and the National Science Foundation of the United States is gratefully acknowledged. We thank D. A. Pierson for her preparation of 2-methylcyclohexyl diazoacetates and preliminary studies of their diazo decomposition and A. Melekhov from the Higher College of Chemistry for his preparation and catalytic studies of rac-2-octyl diazoacetate. 相似文献
17.
Korsunskii B. L. Kalinin V. N. Sitonina G. V. Dubovitskii F. I. Zakharkin L. I. 《Russian Chemical Bulletin》1971,20(8):1712-1713
Conclusions The manometric method was used to study the kinetics of the reaction of phenylacetylene with the complex of decaborane and diethyl sulfide, with the formation of 1-phenyl-o-carborane. The reaction is described by a second order equation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1818, August, 1971. 相似文献
18.
19.
Kessel L Kalinin S Nagaraj RH Larsen M Johansson LB 《Photochemistry and photobiology》2002,76(5):549-554
The intrinsic fluorescence from the human lens on excitation in the UV region, referred to as blue lens autofluorescence, increases with age or in the presence of diabetes. The present study reveals that the relative contribution of compounds responsible for the blue autofluorescence appears to be a constant with age. Three potential candidates for the blue fluorescence were also studied with respect to fluorescence spectroscopic properties. These were argpyrimidine and pentosidine, both advanced glycation end products, and 3-hydroxykynurenine (3-OH-kynurenine), a photooxidative derivative of tryptophan. It was shown that the spectral properties of argpyrimidine and pentosidine are compatible with the observed blue fluorescence of the human lens, whereas the fluorescence from 3-OH-kynurenine is negligible. 相似文献
20.
Glycosides of marine invertebrates. Structure of holothurin A2 from the holothurianHolothuria edulis
The structure of a new glycoside fromHolothuria edulis, holothurin A2, has been established with the aid of periodate oxidation, methylation, Smith degradation, and13C NMR spectroscopy. The structure of the glycoside has been determined as holost-9(11)-ene-3β,12α,17α-triol 3-0-{2-0-[3-0-methyl-β-D-glucopyranosyl-(1→3)-0-β-D-glucopyranosyl-(1→4)-0-β-D-quinovopyranosyl]-4-0-sulfate-β-D-xylopyranoside}. 相似文献