Acceder

Bibliografías temáticas / Bicyclo [6 / Artículos de revistas

Siga este enlace para ver otros tipos de publicaciones sobre el tema: Bicyclo [6.

Artículos de revistas sobre el tema "Bicyclo [6"

Autor: Grafiati

Publicado: 4 de junio de 2021

Última modificación: 17 de febrero de 2022

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 50 mejores artículos de revistas para su investigación sobre el tema "Bicyclo [6".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore artículos de revistas sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

1

Piers, Edward, and Hoi Lun Allan Tse. "A new annulation method. Total syntheses of the sesquiterpenoids (±)-chiloscyphone and (±)-6-epi-chiloscyphone." Canadian Journal of Chemistry 71, no. 7 (1993): 983–94. http://dx.doi.org/10.1139/v93-131.

Texto completo

Resumen

The efficacy of a new annulation method, developed for the construction of functionalized bicyclic compounds, is illustrated by conversion of the β-keto esters 18 and 19 into the bicyclo[4.3.0]non-1-enes 33 and 34, respectively, and by transformation of 2-methoxycarbonylcyclopentanone (20) into the bicyclo[4.3.0]non-6-ene 38 and the bicyclo[5.3.0]dec-7-enes 48 and 51. Application of the method to total syntheses of the structurally unusual sesquiterpenoids (±)-chiloscyphone (16) and (±)-6-epi-chiloscyphone (17) is described.

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Werstiuk, N. H., S. Yeroushalmi, and Hong Guan-Lin. "Synthesis of bicyclic diones and thiones. Facile methylation of the enolates of bicyclo[2.2.1]heptane-2,5-dione and bicyclo[2.2.2]octane-2,5-dione. An AM1 computational study of bicyclic enolates." Canadian Journal of Chemistry 70, no. 3 (1992): 974–80. http://dx.doi.org/10.1139/v92-130.

Texto completo

Resumen

A group of bicyclic ketones and thiones have been synthesized for homenolization studies. Bicyclo[2.2.1]heptane-2,5-dione (6) undergoes unusually rapid tetramethylation giving 3,3,6,6-tetramethylbicyclo[2.2.1]heptane-2,5-dione (1) in good yield. Treatment of 1 with P2S5 in xylene gave 3,3,6,6-tetramethylbicyclo[2.2.1]heptane-2,5-dithione (2) and 3,3,6,6-tetramethyl 15-oxo-bicyclo[2.2.1]heptane-2-thione (3), which was converted into 4 with Raney nickel. Bicyclo[2,2,2]octane-2,5-dione (7), prepared via a Diels–Alder reaction between 2-trimethylsilyloxy-1,3-cyclohexadiene and and α-acetoxyacrylon

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Kasper, Franz, and Tatjana Beier. "Bicyclen; Umsetzungen des 2,2-Di-(hydroxymethyl)-bicyclo [2.2.1] - heptens- (6)." Zeitschrift für Chemie 19, no. 10 (2010): 373. http://dx.doi.org/10.1002/zfch.19790191007.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Brandt, Sigrid, Wolfgang Kirmse, Dietmar Mönch, and Heinz-Jürgen Wroblowsky. "Umlagerungen von 6-Bicyclo[3.2.1]octyl-Kationen." Chemische Berichte 123, no. 4 (1990): 887–93. http://dx.doi.org/10.1002/cber.19901230439.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Mann, Gerhard, Jürgen Braband, and Manfred Mühlstädt. "Exo- und endo-Bicyclo[3,2,2]nonanol-(6)." Zeitschrift für Chemie 9, no. 7 (2010): 265–66. http://dx.doi.org/10.1002/zfch.19690090704.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

Tanaka, Kelly SE, and Andrew J. Bennet. "Article." Canadian Journal of Chemistry 76, no. 4 (1998): 431–36. http://dx.doi.org/10.1139/v98-039.

Texto completo

Resumen

A bicyclo[2.2.2] analogue of the glycosidase inhibitor 1-deoxynojirimycin, 2,6-anhydro-1-deoxymannojirimycin (6), has been synthesized in nine steps from 1,5-anhydro-D-glucitol. This conformationally restricted aza-sugar has been shown to inhibit, albeit weakly, several glycosidase enzymes.Key words: glycosidase, inhibitor, bicyclic, deoxymannojirimycin, deoxynojirimycin.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Dehmlow, Eckehard V., and Roland Kramer. "Preparation and Pyrolysis of Stereoisomeric Bromobicyclo[n.1.0]alkanes ( n = 6, 8 , 10)." Zeitschrift für Naturforschung B 42, no. 4 (1987): 489–94. http://dx.doi.org/10.1515/znb-1987-0416.

Texto completo

Resumen

Abstract The title compounds la-3c were prepared by stereoselective reduction of the respective dibromides. Pyrolysis gave allylic bromides (8, 9, 11) as primary and dienes (10, 12) as secondary products. Product ratios were independent of the stereochemistry of the starting materials. No differences of the rearrangement rates of the stereoisomers were observed in gas phase reactions of the derivatives of bicyclo[6.1.0]- and bicyclo[8.1.0]alkanes. With the larger bicyclo[10.1.0] derivatives, however, distinct differences in the thermal stability of cis-trans-isomers4c/5c or 2c/3c were found in

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Hřebabecký, Hubert, Milena Masojídková, and Antonín Holý. "Synthesis of Novel Conformationally Locked Carbocyclic Nucleosides Derived from 5,5- and 6,6-Bis(hydroxymethyl)bicyclo[2.2.1]heptan-2-ol." Collection of Czechoslovak Chemical Communications 70, no. 4 (2005): 519–38. http://dx.doi.org/10.1135/cccc20050519.

Texto completo

Resumen

(1R*,2R*,3R*,4S*)-3-Amino-6,6-bis(hydroxymethyl)bicyclo[2.2.1]heptan-2-ol (13) was prepared from (bicyclo[2.2.1]hept-5-ene-2,2-diyl)dimethyl dibenzoate (7) viacis-diol8, cyclic sulfate10, and azide12. (1R*,2R*,3S*,4S*)-3-Amino-6,6-bis(hydroxymethyl)bicyclo[2.2.1]-heptan-2-ol (18) and (1R*,2S*,3S*,4S*)-3-amino-5,5-bis(hydroxymethyl)bicyclo[2.2.1]heptan-2-ol (19) were obtained by addition of chromyl azide to double bond of7, chromatographic separation, debenzoylation and hydrogenation of resulting azides14and16. The amines13,18, and19were used to build (1R*,2R*,3R*,4S*)- (21a), (1R*,2R*,3S*,4S*)

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Piers, Edward, Grace L. Jung, and Edward H. Ruediger. "Synthesis of functionalized bicyclo[3.2.1]octa-2,6-dienes by thermal rearrangement of substituted 6-exo-(1-alkenyl)bicyclo[3.1.0]hex-2-ene systems." Canadian Journal of Chemistry 65, no. 3 (1987): 670–82. http://dx.doi.org/10.1139/v87-115.

Texto completo

Resumen

Thermolysis of each of the enol silyl ethers 31–35 affords, cleanly and efficiently, the bicyclo[3.2.1]octadienes 36–40, respectively. Similarly, thermal rearrangement of the enol silyl ether 50 provides the diene 51. Hydrolysis of 36, 37, and 39, and decarbomethoxylation of the resultant keto esters 41, 42, and 44, gives the ketones 46–48, respectively. The ketone 46 is also obtained by acid hydrolysis of 51. Conversion of 6-methyl-1-hepten-4-yn-3-ol (56) into the enol ether 63 is described. Thermolysis of 63 gives 64, which, upon acid hydrolysis, affords 65. Thermolysis of the enones 68 and

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Hřebabecký, Hubert, Milena Masojídková, Martin Dračínský, and Antonín Holý. "Synthesis of Novel Conformationally Locked Carbocyclic Nucleosides Derived from 3-(Hydroxymethyl)bicyclo[2.2.1]heptane-2,5-diol." Collection of Czechoslovak Chemical Communications 71, no. 6 (2006): 871–88. http://dx.doi.org/10.1135/cccc20060871.

Texto completo

Resumen

(1R*,2R*,3R*,4R*,5R*,6S*)-3-Amino-5-(benzyloxy)-6-(hydroxymethyl)bicyclo[2.2.1]heptan-2-ol (18) was prepared in seven easy steps from benzyl (1R*,2S*,3S*,4S*)-3-(benzyloxy)bicyclo[2.2.1]hept-5-ene-2-carboxylate (10). Reaction of amine18with ethylN-((2E)-3-ethoxymethacryloyl)carbamate afforded 1-[(1R*,2R*,3R*,4R*,5S*,6R*)-6-(benzyloxy)-3-hydroxy-5- (hydroxymethyl)bicyclo[2.2.1]heptan-2-yl]-5-methylpyrimidine-2,4(1H,3H)-dione (21) and after deprotection by transfer hydrogenation, free thymine analogue22. The thymine derivative21was converted to 2,3'-anhydronucleoside26. Treatment of the benzyl d

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Loughlin, Wendy A. "A Facile Approach to Bicyclo[n.2.0]alkan-1-ols: An Overview." Australian Journal of Chemistry 57, no. 4 (2004): 335. http://dx.doi.org/10.1071/ch03213.

Texto completo

Resumen

Bicyclo[n.2.0]alkan-1-ols are an integral part of various frameworks of natural products. The reaction of the lithium enolates of simple ketones with (±)-phenyl vinyl sulfoxide and the controlled formation of bicyclo[n.2.0]alkan-1-ols was investigated. Facile access to bicyclo[n.2.0]alkan-1-ols (n = 3–6) bearing a bridgehead hydroxyl group was obtained. The ratio of bicyclo[n.2.0]alkan-1-ols (n = 3–6) to alkyated ketone was found to be dependent on enolate reactivity, electrophile conversion, time, reaction temperature, concentration, as well as the stability and steric strain observed in the

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Hřebabecký, Hubert, Martin Dračínský, and Antonín Holý. "Synthesis of Novel Carbocyclic Nucleoside Analogues Containing Bicyclo[2.2.1]hept-2-ene-2-methanol." Collection of Czechoslovak Chemical Communications 73, no. 1 (2008): 44–58. http://dx.doi.org/10.1135/cccc20080044.

Texto completo

Resumen

Starting ethyl (1R*,2R*,3R*,4S*)-3-bromobicyclo[2.2.1]hept-5-ene-2-carboxylate (9) was reduced with LiAlH4and benzoylated giving [(1R*,2R*,3R*,4S*)-3-bromobicyclo[2.2.1]hept-5-en-2-yl]methyl benzoate (11). Treatment of11with NaN3and CrO3in acetic acid afforded [(1R*,2S*,3R*,4R*,5S*,6R*)-6-azido-3-bromo-5-hydroxybicyclo[2.2.1]hept-2-yl]methyl benzoate (12a) and [(1R*,2S*,3S*,4R*,5S*,6R*)-5-azido-3-bromo-6-hydroxybicyclo[2.2.1]heptan-2-yl]-methyl benzoate (12b). These key intermediates were separated and converted in five reaction steps to (1R*,2R*,3S*,4S*)-3-[(5-amino-6-chloropyrimidin-4-yl)ami

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Carrupt, Pierre-Alain, and Pierre Vogel. "Double bond pyramidalization in bicyclic alkanes. Ab initio mo calculations on bicyclo[2.2.1] hept-2-ene, bicyclo[2.2.1] hex-2-ene and bicyclo[3.2.1] oct-6-ene derivatives." Journal of Molecular Structure: THEOCHEM 124, no. 1-2 (1985): 9–23. http://dx.doi.org/10.1016/0166-1280(85)87017-2.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Cagnoli, Nera, Paolo Ceccherelli, Massimo Curini, Maria Carla Marcotullio, and Ernest Wenkert. "A Facile Syntheses of 6-Bicyclo[3.2.1]octanones." Synthetic Communications 17, no. 11 (1987): 1261–71. http://dx.doi.org/10.1080/00397918708057747.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Tsurusaki, Akihiro, Jun Kamiyama, and Soichiro Kyushin. "Tetrasilane-Bridged Bicyclo[4.1.0]heptasil-1(6)-ene." Journal of the American Chemical Society 136, no. 37 (2014): 12896–98. http://dx.doi.org/10.1021/ja507279z.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Hartmann, M. "Synthese und Umlagerung von Bicyclo[3,2,2]nonen-(6)." Zeitschrift für Chemie 7, no. 3 (2010): 101–2. http://dx.doi.org/10.1002/zfch.19670070304.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Dastlik, KA, EL Ghisalberti, BW Skelton, and AH White. "Structural Studies of Bicyclo[3.2.1]octane and Bicyclo[2.2.2]octane Diols." Australian Journal of Chemistry 45, no. 5 (1992): 959. http://dx.doi.org/10.1071/ch9920959.

Texto completo

Resumen

The crystal structures of 4 α,5 α and 4 β,5 β-dihydroxyisoeremone (4) and (5), incorporating the bicyclo[2.2.2]octane skeleton, and the bicyclo[3.2.l]octane diol (6) have been determined by X-ray crystallographic methods.

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Frei, Sibylle, Adam K. Katolik, and Christian J. Leumann. "Synthesis, biophysical properties, and RNase H activity of 6’-difluoro[4.3.0]bicyclo-DNA." Beilstein Journal of Organic Chemistry 15 (January 8, 2019): 79–88. http://dx.doi.org/10.3762/bjoc.15.9.

Texto completo

Resumen

Here we present the synthesis, the biophysical properties, and the RNase H profile of 6’-difluorinated [4.3.0]bicyclo-DNA (6’-diF-bc4,3-DNA). The difluorinated thymidine phosphoramidite building block was synthesized starting from an already known gem-difluorinated tricyclic glycal. This tricyclic siloxydifluorocyclopropane was converted into the [4.3.0]bicyclic nucleoside via cyclopropane ring-opening through the addition of an electrophilic iodine during the nucleosidation step followed by reduction. The gem-difluorinated bicyclic nucleoside was then converted into the corresponding phosphor

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Yin, Jianguo, and W. M. Jones. "Transition-metal complexes of bicyclo[3.1.0]hex-5-ene and bicyclo[4.1.0]hept-6-ene." Organometallics 12, no. 6 (1993): 2013–14. http://dx.doi.org/10.1021/om00030a008.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Morkan, Izzet Amour, та Ayşe Uztetik Morkan. "Cycloaddition Reactions of (η6-Tropone)tricarbonylmetal(0) Complexes of Group 6 Metals with Alkynes". Collection of Czechoslovak Chemical Communications 67, № 11 (2002): 1635–46. http://dx.doi.org/10.1135/cccc20021635.

Texto completo

Resumen

(η6-Cyclohepta-2,4,6-trien-1-one)tricarbonylmetal(0) complexes of chromium (2a), molybdenum (2b), and tungsten (2c) are formed when tris(acetonitrile)tricarbonylchromium(0), -molybdenum(0), and -tungsten(0), respectively, are treated photochemically with tropone (cyclohepta-2,4,6-trien-1-one) 1. UV photolysis of 2a-2c and RC≡CR' (R = R' = Ph, Me3Si, Et; R = Ph, R' = Me3Si) in toluene gives the [6+2] cycloadducts, (η4,η2-8,9-diphenylbicyclo[4.2.1]nona-3,5,8-trien-1-one)tricarbonylmetal(0) 3a-3c, (η4,η2-8,9-bis(trimethylsilyl)bicyclo[4.2.1]nona-3,5,8-trien-1-one)tricarbonylmetal(0) 4a-4c, (η4,η2

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Jasiński, Radomir, Oskar Koifman, and Andrzej Barański. "A B3LYP/6-31G(d) study of Diels-Alder reactions between cyclopentadiene and (E)-2-arylnitroethenes." Open Chemistry 9, no. 6 (2011): 1008–18. http://dx.doi.org/10.2478/s11532-011-0088-5.

Texto completo

Resumen

AbstractThe B3LYP/6-31G(d) simulations of competing CDA and HDA reactions between cyclopentadiene and (E)-2-arylnitroethenes prove that regardless of the medium polarity, the processes leading to respective 5-nitro-6-aryl-bicyclo-[2,2,0]-hept-2-enes 3,4 (paths A and B) should be most favoured, and the more electrophilic (E)-2-(p-nitrophenyl)-nitroethene should be more reactive than the less electrophilic (E)-2-(p-methoxyphenyl)-nitroethene. Asymmetry of the transition complexes on the favoured pathways increases with increase of medium polarity, but not sufficiently to enforce the zwitterionic

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

Davenel, Vincent, Chloé Puteaux, Christian Nisole, Fabien Fontaine-Vive, Jean-Marie Fourquez, and Véronique Michelet. "Indium-Catalyzed Cycloisomerization of 1,6-Cyclohexenylalkynes." Catalysts 11, no. 5 (2021): 546. http://dx.doi.org/10.3390/catal11050546.

Texto completo

Resumen

Efficient four- and five-step routes to access functionalized bicyclo[3.2.1]oct-2-ene and bicyclo[3.3.1]nonadiene via indium-mediated cycloisomerization of 1,6-enynes has been developed. This atom-economical catalytic process was optimized and relied on the efficiency of InCl3 leading to the preparation of functionalized bicyclic adducts in up to 99% isolated yield. The cyclization occurred on two different processes (5-exo versus 6-endo pathway) and were influenced by the substitution of the alkynyl moiety. The exo process was favored for non-substituted alkynes whereas the endo pathway was g

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Yates, Peter, Rupinder S. Grewal, Peter C. Hayes, and Jeffery F. Sawyer. "Synthesis of cedranoid sesquiterpenes. V. The biotols." Canadian Journal of Chemistry 66, no. 11 (1988): 2805–15. http://dx.doi.org/10.1139/v88-434.

Texto completo

Resumen

Reduction of dimethyl 3-hydroxy-4,4,8-trimethyl-6-oxo-cis-bicyclo[3.3.0]octa-2,7-diene-1,2-dicarboxylate (8) with lithium and ammonia gives dimethyl 3-hydroxy-4,4,exo-8-trimethyl-6-oxo-cis-bicyclo[3.3.0]oct-2-ene-1,2-dicarboxylate (9), which on acetylation, reduction with sodium borohydride, and methanolysis gives dimethyl 3,exo-6-dihydroxy-4,4,exo-8-trimethyl-cis-bicyclo[3.3.0]oct-2-ene-1,2-dicarboxylate (12). This on 2-decarbomethoxylation followed by treatment with lithium acetylide in the presence of cerium trichloride gives methyl 3-ethynyl-3,exo-6-dihydroxy-4,4,exo-8-trimethyl-cis-bicycl

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Piers, Edward, and Grace L. Jung. "Thermal rearrangement of functionalized 6-exo-(1-alkenyl)bicyclo[3.1.0]hex-2-enes. A total synthesis of (±)-sinularene." Canadian Journal of Chemistry 63, no. 4 (1985): 996–98. http://dx.doi.org/10.1139/v85-167.

Texto completo

Resumen

A total synthesis of the racemic form of the marine sesquiterpenoid (−)-sinularene (1) is described. The key step of the synthesis involved the stereoselective thermal rearrangement of the highly functionalized bicyclo[3.1.0]hexene 12 to provide, in 86% yield, the substituted bicyclo[3.2.1]octadiene 13. Conversion of the latter substance into (±)-sinularene (1) was accomplished via an efficient 4-step sequence.

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Boehringer, Régis, Philippe Geoffroy, and Michel Miesch. "Base catalyzed synthesis of bicyclo[3.2.1]octane scaffolds." Organic & Biomolecular Chemistry 13, no. 25 (2015): 6940–43. http://dx.doi.org/10.1039/c5ob00933b.

Texto completo

Resumen

A base-catalyzed and time controlled reaction of 1,3-cyclopentanediones tethered to activated olefins afforded in high yields either bicyclo[3.2.1]octane-6,8-dione or bicyclo[3.2.1]octane-6-carboxylate derivatives.

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Gray, Brian D., Catherine M. McMillan, J. Allen Miller, and Michael Moore. "Bicyclo[3.2.1]oct-6-enes via (3+2)cycloaddition." Tetrahedron Letters 28, no. 2 (1987): 235–38. http://dx.doi.org/10.1016/s0040-4039(00)95695-8.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

Zhu, Fang-Hua, Jun-Xiao Yang, Zhi-Hua Mao, and Ru-Gang Xie. "1-[Bicyclo[4.2.0]octa-1(6),2,4-trien-3-yl]-3-[bicyclo[4.2.0]octa-1(6),2,4-trien-3-ylmethyl]imidazolium hexafluorophosphate." Acta Crystallographica Section E Structure Reports Online 64, no. 2 (2008): o434. http://dx.doi.org/10.1107/s1600536807067086.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

Yates, Peter, D. Jean Burnell, Vernon J. Freer, and Jeffery F. Sawyer. "Synthesis of cedranoid sesquiterpenes. III. Functionalization at carbon 4." Canadian Journal of Chemistry 65, no. 1 (1987): 69–77. http://dx.doi.org/10.1139/v87-012.

Texto completo

Resumen

Dimethyl 6,6-dimethyl-5,7-dioxobicyclo[2.2.2]oct-2-ene-2,3-dicarboxylate (8) on irradiation in acetophenone gives dimethyl 6,6-dimethyl-4,7-dioxotricyclo[3.2.1.02,8]octane-1,8-dicarboxylate (13), which on treatment with lithium dimethylcuprate followed by monodecarbomethoxylation gives methyl 4,4-endo-8-trimethyl-3,6-dioxo-cis-bicyclo[3.3.0]octane-1-carboxylate (17). Similar irradiation of dimethyl 4,6,6-trimethyl-5,7-dioxobicyclo[2.2.2]oct-2-ene-2,3-dicarboxylate (24) and its 7,7-ethylenedioxy derivative (25) followed by treatment with DBU and concentrated H2SO4, respectively, gives dimethyl

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Frei, Sibylle, Andrei Istrate, and Christian J. Leumann. "6’-Fluoro[4.3.0]bicyclo nucleic acid: synthesis, biophysical properties and molecular dynamics simulations." Beilstein Journal of Organic Chemistry 14 (December 20, 2018): 3088–97. http://dx.doi.org/10.3762/bjoc.14.288.

Texto completo

Resumen

Here we report on the synthesis, biophysical properties and molecular modeling of oligonucleotides containing unsaturated 6’-fluoro[4.3.0]bicyclo nucleotides (6’F-bc4,3-DNA). Two 6’F-bc4,3 phosphoramidite building blocks (T and C) were synthesized starting from a previously described [3.3.0]bicyclic sugar. The conversion of this sugar to a gem-difluorinated tricyclic intermediate via difluorocarbene addition followed either by a NIS-mediated or Vorbrüggen nucleosidation yielded in both cases the β-tricyclic nucleoside as major anomer. Subsequent desilylation and cyclopropane ring opening of th

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

J. Leumann, Christian, and Samuel Luisier. "Screening the Structural Space of Bicyclo-DNA: Synthesis and Properties of Bicyclo-DNA Functionalized at C(6’)." HETEROCYCLES 82, no. 1 (2010): 775. http://dx.doi.org/10.3987/com-10-s(e)65.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Trost, Barry M., Patrick J. McDougall, Olaf Hartmann, and Peter T. Wathen. "Asymmetric Synthesis of Bicyclo[4.3.1]decadienes and Bicyclo[3.3.2]decadienes via [6 + 3] Trimethylenemethane Cycloaddition with Tropones." Journal of the American Chemical Society 130, no. 45 (2008): 14960–61. http://dx.doi.org/10.1021/ja806979b.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Pigou, PE, and DK Taylor. "Activation Parameters for Ring Opening of (Bicyclo[n.1.1]alk-1-yl)methyl Radicals." Australian Journal of Chemistry 44, no. 10 (1991): 1417. http://dx.doi.org/10.1071/ch9911417.

Texto completo

Resumen

Ring opening of the (bicyclo[1.1.1]pent-1-yl)methyl (4), (bicyclo[2.1.1]hex-1-yl)methyl (5) and (bicyclo[3.1.1]hept-1-yl)methyl (6) radicals has been investigated by semiempirical molecular orbital theory MINDO/3 and AM1) and by experiment. Our results indicate that (4) ring-opens extremely rapidly, with an estimated energy barrier of less than 22 kJ mol-1. The higher homologues (5) and (6) rearrange more slowly with barriers of about 42.2 and 46.0 kJ mol-1 respectively. This trend is also observed in the MINDO/3 and AM1 results, with the latter giving the better agreement with experiment.

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Šála, Michal, Hubert Hřebabecký, Milena Masojídková, and Antonín Holý. "Synthesis of Novel Racemic Conformationally Locked Carbocyclic Nucleosides Derived from 7-Substituted Bicyclo[2.2.1]hept-5-ene-2,2-dimethanols." Collection of Czechoslovak Chemical Communications 71, no. 5 (2006): 635–49. http://dx.doi.org/10.1135/cccc20060635.

Texto completo

Resumen

(1R*,4R*,7S*)-7-Aminobicyclo[2.2.1]hept-5-ene-2,2-dimethanol (15) was prepared in four easy steps from bicyclo[2.2.1]hept-5-ene-2,2-dimethanol (10). Reaction of amine 15 with ethyl N-((E)-3-ethoxymethacryloyl)carbamate afforded thymine derivatives 17a. The amine 15 was used to construct 6-chloro-9H-purine derivative 19a, 2-amino-6-chloro-9H-purine derivative 22a. Ammonolysis of 19a led to the adenine derivative 20a. Treatment of 22a with trifluoroacetic acid afforded guanine nucleoside 23a. (1R*,4R*,7S*)-7-[6-(Cyclopropylamino)-9H-purin-9-yl]bicyclo[2.2.1]hept-5-ene-2,2-dimethanol (21a) and (1

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Christoffers, Jens, Wolfgang Frey, Heiko Scharl, and Angelika Baro. "Absolute Konfiguration von (+)-1,2,3,4,6,7,8,8a-Octahydro-6-isochinolon- 8a-carbonsäuremethylester und die Stereochemie einer Kupfer-katalysierten asymmetrischen Michael-Reaktion / Absolute Configuration of Methyl (+)-1,2,3,4,6,7,8,8a-Octahydro-6-isoquinolone-8a-carboxylate and Stereochemistry of a Copper-Catalyzed Asymmetric Michael Reaction." Zeitschrift für Naturforschung B 59, no. 4 (2004): 375–79. http://dx.doi.org/10.1515/znb-2004-0404.

Texto completo

Resumen

AbstractEnantiopure Boc-protected piperidine derivative (+)-5c, with a quaternary stereocenter, was obtained by copper-catalyzed, L-valine diethylamide-mediated Michael reaction. For determination of the absolute configuration, 5c was derivatized by cyclization with pyrrolidine/AcOH to give compound 6 with bicyclo[4.4.0]-constitution, deprotection of the amino function with TFA and subsequent reaction with 2-iodobenzoic acid to yield the crystalline bicyclic amide 7. X-ray crystallographic analysis confirmed the constitution of compounds 5c and 6 and established the (R) configuration of 7. Thu

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

Hřebabecký, Hubert, Martin Dračínský, and Antonín Holý. "New carbocyclic nucleoside analogues built on a bicyclo[2.2.2]octane-2,2-dimethanol template." Collection of Czechoslovak Chemical Communications 74, no. 9 (2009): 1425–41. http://dx.doi.org/10.1135/cccc2009090.

Texto completo

Resumen

(1R*,4S*,6S*)-6-(6-Chloro-9H-purin-9-yl)bicyclo[2.2.2]octane-2,2-dimethanol (22) and (1R*,4R*,5S*)-5-(6-chloro-9H-purin-9-yl)bicyclo[2.2.2]octane-2,2-dimethanol (17) were prepared from (1R*,4R*)-bicyclo[2.2.2]oct-5-ene-2,2-dimethanediyl dibenzoate (7) using two approaches. The first procedure consists in hydroboration of 7, separation of obtained 6-exo-hydroxy derivative 8 and 5-exo-hydroxy derivative 9, conversion of 8 and 9 to endo-hydroxy derivatives 12 and 13, respectively, and the Mitsunobu reaction with 6-chloropurine. Only 5-(6-chloropurinyl) analogue 16 was obtained in an acceptable yi

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Levchenko, Konstantin S., Gregory E. Adamov, Dmitri Yu Demin, et al. "Di(bicyclo[4.2.0]octa-1(6),2,4-trien-3-yl)dimethylsilane." Molbank 2020, no. 4 (2020): M1160. http://dx.doi.org/10.3390/m1160.

Texto completo

Resumen

Di(bicyclo[4.2.0]octa-1(6),2,4-trien-3-yl)dimethylsilane (DiBCB-DMS) was synthesized as a promising monomer for polymer coating production with good dielectric properties for electronics. DiBCB-DMS was characterized by 1H, 13C NMR, IR, UV/VIS, and HRMS analysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Šála, Michal, Hubert Hřebabecký, Martin Dračínský, et al. "Synthesis of novel racemic carbocyclic nucleosides derived from 5,6-disubstituted norbornene." Collection of Czechoslovak Chemical Communications 75, no. 1 (2009): 1–20. http://dx.doi.org/10.1135/cccc2009116.

Texto completo

Resumen

Novel class of the carbocyclic nucleosides based on bicyclo[2.2.1]heptene/heptane was prepared by two approaches. Thymine analogues were synthesized starting from methyl (1R*,4S*)-bicyclo[2.2.1]hepta-2,5-diene-2-carboxylate1by Michael addition of the thymine salt to the double bond as the key step. The yield and ratio of the isomers of this reaction depended on the used base (DBU, K2CO3). Purine nucleoside analogues were synthesized by the linear synthesis, the purine nucleobase was build-up on the amino group. The amino groups (exo/endoconfiguration) were introduced to the scaffold by the Cur

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Werstiuk, Nick Henry, and Jiangong Ma. "An ab initio study on the magnetic susceptibility and magnetically induced current density distribution of the bicyclo[3.2.1]octa-3,6-dien-2-yl anion." Canadian Journal of Chemistry 77, no. 5-6 (1999): 752–59. http://dx.doi.org/10.1139/v99-049.

Texto completo

Resumen

The molecular susceptibility and the atomic contributions including the basin and surface components calculated at the RHF/6-31+G(d)//6-31+G(d) level of theory along with vector current densities obtained at the 6-31++G(d,p)//6-31+G(d) and 6-31+G(d)//6-31+G(d) levels are reported for benzene (1) and correlated - the agreement is excellent - with the results obtained by Keith and Bader with the 6-311++G(2d,2p) basis. This validates our similar studies on the bicyclo[3.2.1]octa-3,6-dien-2-yl anion (2) - initially considered to be a bishomoaromatic species - its parent hydrocarbon bicyclo[3.2.1]o

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Hertkorn, N., and F. H. Köhler. "Selektive Metallierung von BicycIo[3.2.1]octa-2,6-dien, II Distannylierte Derivate und stannylierte tricyclische Sekundärprodukte / Selective Metalation of Bicyclo[3.2.1]octa-2,6-diene, II Distannylated Derivatives and Stannylated Tricyclic Secondary Products." Zeitschrift für Naturforschung B 43, no. 11 (1988): 1405–15. http://dx.doi.org/10.1515/znb-1988-1105.

Texto completo

Resumen

Abstract Distannylated bicyclo[3.2.1]octa-2,6-diene (1) with (CH3)3 Sn groups in positions exo-4 and 7 (7a), endo-4 and 7 (7b), exo-4 and 6 (7c), and probably exo-4 and endo-4 (7d) are obtained when 1 is treated first with an excess of n-BuLi/t-BuOK in alkane and then with (CH3)3 SnCl. Byproducts are monostannylated derivatives of 1 and l,4-bis(trimethylstannyl)but-2-ene (3). The formation of 7a/b/c is best understood when the two possible bicyclo[3.2.1]octa-2,6-dienyl dianions are generated as intermediates. 3,exo-4-Bis(trimethylstannyl)bicyclo[3.2.1]octa-2,6-diene (7e) is ob-tained from the

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Sow, Boubacar, Gabriel Bellavance, Francis Barabé, and Louis Barriault. "One-pot Diels–Alder cycloaddition/gold(I)-catalyzed 6-endo-dig cyclization for the synthesis of the complex bicyclo[3.3.1]alkenone framework." Beilstein Journal of Organic Chemistry 7 (July 22, 2011): 1007–13. http://dx.doi.org/10.3762/bjoc.7.114.

Texto completo

Resumen

The rapid synthesis of bicyclo[m.n.1]alkanone cores possessing quaternary carbon centers adjacent to a bridged ketone represents a significant synthetic challenge. This type of architectural feature is embedded in various complex biologically active compounds such as hyperforin and garsubellin A. Herein, we report a highly diastereoselective one-pot Diels–Alder reaction/Au(I)-catalyzed carbocyclization to generate bicyclo[3.3.1]alkanones in yields ranging from 48–93%.

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Vogel, Claus, and Paul Delavier. "A synthesis of the 6-aza-bicyclo(3,2,2)nonane skeleton." Tetrahedron Letters 30, no. 14 (1989): 1789–92. http://dx.doi.org/10.1016/s0040-4039(00)99580-7.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Lal, Kasturi, and Robert G. Salomon. "6-Substituted bicyclo[2.2.1]hept-5-en-2-one ketals." Journal of Organic Chemistry 54, no. 11 (1989): 2628–32. http://dx.doi.org/10.1021/jo00272a033.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Runge, Andreas, and Wolfram Sander. "6-bromo-6-(trimethylstannyl)bicyclo[3.1.0]hexane as a thermal precursor of 1,2-cyclohexadiene." Tetrahedron Letters 27, no. 48 (1986): 5835–38. http://dx.doi.org/10.1016/s0040-4039(00)85340-x.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

Dejmek, Milan, Hubert Hřebabecký, Martin Dračínský, and Antonín Holý. "Synthesis of Novel Carbocyclic Nucleoside Analogues Derived from 2-(Hydroxymethyl)bicyclo[2.2.1]heptane." Collection of Czechoslovak Chemical Communications 72, no. 11 (2007): 1523–44. http://dx.doi.org/10.1135/cccc20071523.

Texto completo

Resumen

The key intermediates, [(1R*,2R*,4R*,6R*)-6- (12a) and [(1R*,2R*,4R*,5S*)-5-(hydroxymethyl)- bicyclo[2.2.1]heptan-2-yl]methyl benzoates (12b), were prepared from (1R*,2S*,4R*)- bicyclo[2.2.1]hept-5-en-2-ylmethyl benzoate by hydroboration, oxidation with pyridinium dichromate and subsequent reduction of the thus obtained ketones. The Mitsunobu reaction of12aand12bwith 6-chloropurine afforded 6-chloropurine derivatives, which were converted into others purine analogues. Thymine analogues were prepared from [(1R*,2R*,4S*,6S*)-6- (25a) and [(1R*,2S*,4R*,5S*)-5-aminobicyclo[2.2.1]heptan-2-yl]methan

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Verma, Sharad K., Que H. Nguyen, James M. MacDougall, Everly B. Fleischer, and Harold W. Moore. "Oxy-Cope Rearrangements of Bicyclo[3.2.0]heptenones. Synthesis of Bicyclo[4.2.1]non-1(4)-en-6-ones and Bicyclo[5.2.1]dec-1(10)-en-5-ones." Journal of Organic Chemistry 65, no. 11 (2000): 3379–86. http://dx.doi.org/10.1021/jo991765w.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Tănase, Constantin I., Constantin Drăghici, Anamaria Hanganu, et al. "1′-Homocarbocyclic Nucleoside Analogs with an Optically Active Substituted Bicyclo[2.2.1]Heptane Scaffold." Chemistry Proceedings 3, no. 1 (2020): 16. http://dx.doi.org/10.3390/ecsoc-24-08367.

Texto completo

Resumen

An optically active bicyclo[2.2.0]heptane fragment was introduced in the molecule of new 1′-homonucleosides on a 2- 6-chloro-amino-purine scaffold to obtain 6-substituted carbocyclicnucleozide analogs as antiviral compounds. The synthesis was realized by a Mitsunobu reaction of the base with the corresponding bicyclo[2.2.0]heptane intermediate, and then the nucleoside analogs were obtained by substitution of the 6-chlorime with selected pharmaceutically accepted amines. A molecular docking study of the compounds on influenza, HSV and low active coronavirus was realized. Experimental screening

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Marotta, Emanuela, Ilaria Pagani, Paolo Righi, Goffredo Rosini, Valerio Bertolasi, and Alessandro Medici. "Pure enantiomers of bicyclo[3.2.0]hept-3-en-6-ones and bicyclo[3.2.0]hept-3-en-6-endo-ols: Resolution, absolute configuration and optical properties." Tetrahedron: Asymmetry 6, no. 9 (1995): 2319–28. http://dx.doi.org/10.1016/0957-4166(95)00308-c.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Collis, Gavin E., Dylan Jayatilaka, and Dieter Wege. "Cyclopropa-Fused Quinones. The Generation and Trapping of Bicyclo[4.1.0]hepta-1(6),3-diene-2,5-dione and 1H-Cyclopropa[b]naphthalene-2,7-dione." Australian Journal of Chemistry 50, no. 5 (1997): 505. http://dx.doi.org/10.1071/c96204.

Texto completo

Resumen

The title compounds (3) and (4) have been generated at low temperature by debromosilylation of 1-bromo-6-trimethylsilylbicyclo[4.1.0]hept-3-ene-2,5-dione (23) and 1a-bromo-7a-trimethylsilyl-1a,7a-dihydro-1H-cyclopropa[b]naphthalene-2,7-dione (38) respectively. Both cyclopropa-fused quinones are reactive but each could be trapped with furan to give a pair of cycloadducts, which were remarkably resistant to cycloreversion. In the absence of added trapping agent, the cyclopropanaphthoquinone (4) was intercepted by fluoride ion to give 1a-fluoro-1a,7a-dihydro-1H-cyclopropa[b]naphthalene-2,7-dione

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Ahlenstiel, Eckart, Wolfgang Kliegel, Steven J. Rettig, and James Trotter. "Structural studies of organoboron compounds. LVII. Synthesis and structure of bicyclic boron-nitrogen betaines. 1-Methyl-5-(3-nitrophenyl)-4,6,9-trioxa-1-azonia-5-boratabicyclo[3.3.1]nonane and 3,3,4-trimethyl-1-(3-nitrophenyl)-2,6,7-trioxa-3-azonia-1-boratabicyclo[2.2.2]octane." Canadian Journal of Chemistry 71, no. 2 (1993): 263–71. http://dx.doi.org/10.1139/v93-038.

Texto completo

Resumen

The syntheses and structures of the bicyclic boron-nitrogen betaines 1-methyl-5-(3-nitrophenyl)-4,6,9-trioxa-1-azonia-5-boratabicyclo[3.3.1]nonane, 7a, and 3,3,4-trimethyl-1-(3-nitrophenyl)-2,6,7-trioxa-3-azonia-1-boratabicyclo[2.2.2]-octane, 14a, are reported. Crystals of 7a are orthorhombic, a = 20.256(2), b = 37.652(2), c = 6.642(1) Å, Z = 16, space group Fdd2, and those of 14a are orthorhombic, a = 21.402(2), b = 11.334(3), c = 11.248(2) Å, Z = 8, space group Pbca. The structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.038 and 0.045 (

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Wermuth, Urs D., Ian D. Jenkins, Raymond C. Bott, Karl A. Byriel, and Graham Smith. "Some Stereochemical Aspects of the Strecker Synthesis and the Bucherer - Bergs Reaction." Australian Journal of Chemistry 57, no. 5 (2004): 461. http://dx.doi.org/10.1071/ch03202.

Texto completo

Resumen

Both the Strecker and Bucherer–Bergs reactions convert the norbornane keto ester methyl bicyclo[2.2.1]hept-6-one-2-endo-carboxylate into the lactam 6-endo-aminobicyclo[2.2.1]heptane-2-endo-carboxylic acid-γ-lactam-6-exo-carboxylic acid. This lactam is unusually stable and cannot be hydrolyzed to the corresponding amino acid. The stereochemistry in the Strecker reaction, in which the amino group is endo, is contrary to that expected from literature precedent. The stereochemistry in the Bucherer–Bergs reaction, in which the amino group is also endo, has been confirmed by X-ray crystallographic a

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!