Accedi

Bibliografie tematiche / Pyridine phosphonate / Articoli di riviste

Segui questo link per vedere altri tipi di pubblicazioni sul tema: Pyridine phosphonate.

Articoli di riviste sul tema "Pyridine phosphonate"

Autore: Grafiati

Pubblicato: 1 marzo 2025

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Vedi i top-50 articoli di riviste per l'attività di ricerca sul tema "Pyridine phosphonate".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Vedi gli articoli di riviste di molte aree scientifiche e compila una bibliografia corretta.

1

Kolodiazhna, O. O., E. V. Gryshkun, A. O. Kolodiazhna, S. Yu Sheiko e O. I. Kolodiazhnyi. "Catalytic phosphonylation of C=X electrophiles". Reports of the National Academy of Sciences of Ukraine, n. 12 (dicembre 2020): 75–84. http://dx.doi.org/10.15407/dopovidi2020.12.075.

Testo completo

Abstract (sommario):

A method for the catalytic phosphonylation of C = X electrophiles has been developed. Pyridinium perchlorate is an effective catalyst for the phosphonylation reaction of trialkyl phosphites with various electrophiles C = X (X = O, S, N). The reaction leads to the formation of corresponding α-substituted phosphonates in high yields. The reaction leading to the formation of bisphosphonates represents the highest interest. It was found that the nucleo philic attack of triethyl phosphite on the electron-deficient carbon of the C = X group leads to the formation of beta ine, which reacts with pyridinium perchlorate to form alkoxyphosphonium perchlorate and pyridine. Quasiphosphonium salt is unstable and decomposes to form phosphonate, alkene, and perchloric acid, which reacts with pyridine to regenerate pyridinium perchlorate. The intermediate formed from the pyridinium halide decomposes to form alkyl halide. The general strategy of the proposed method for introducing phosphonate groups into a polyprenyl mole cule consisted in the sequential treatment of hydroxyl-containing a compound with the Swern reagent with the con version of the C—OH group into a carbonyl one. Subsequent phosphonylation of the carbonyl-containing interme diate with the reagent (EtO)3P/[PyH] + ClO 4– leads to the formation of hydroxyalkylbisphosphonate. The synthe sized prenyl bisphosphonates have a pronounced biological activity. These include, for example, enolpyruvylshikimate-3- phosphate synthase (EPSP), farnesyl protein transferase (FPTase), as well as HIV protease, which are of interest as potential biologically active substances.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Fang, Hua, Mei-Juan Fang, Xiao-Xia Liu, Jing-Jing Lin e Yu-Fen Zhao. "Dimethyl [phenyl(pyridine-4-carboxamido)methyl]phosphonate". Acta Crystallographica Section E Structure Reports Online 61, n. 2 (22 gennaio 2005): o408—o409. http://dx.doi.org/10.1107/s1600536805001492.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Zare, Davood, Alessandro Prescimone, Edwin C. Constable e Catherine E. Housecroft. "Where Are the tpy Embraces in [Zn{4′-(EtO)2OPC6H4tpy}2][CF3SO3]2?" Crystals 8, n. 12 (10 dicembre 2018): 461. http://dx.doi.org/10.3390/cryst8120461.

Testo completo

Abstract (sommario):

In this paper, the bromo- and phosphonate-ester-functionalized complexes [Zn(1)2][CF3SO3]2 and [Zn(2)2][CF3SO3]2 (1 = 4′-(4-bromophenyl)-2,2′:6′,2″-terpyridine, 2 = diethyl (4-([2,2′:6′,2″-terpyridin]-4′-yl)phenyl)phosphonate) are reported. The complexes have been characterized by electrospray mass spectrometry, IR and absorption spectroscopies, and multinuclear NMR spectroscopy. The single-crystal structures of [Zn(1)2][CF3SO3]2.MeCN.1/2Et2O and [Zn(2)2][CF3SO3]2 have been determined and they confirm {Zn(tpy)2}2+ cores (tpy = 2,2′:6′,2″-terpyridine). Ongoing from X = Br to P(O)(OEt)2, the {Zn(4′-XC6H4tpy)2}2+ unit exhibits significant “bowing” of the backbone, which is associated with changes in packing interactions. The [Zn(1)2]2+ cations engage in head-to-tail 4′-Phtpy...4′-Phtpy embraces with efficient pyridine...phenylene π-stacking interactions. The [Zn(2)2]2+ cations pack with one of the two ligands involved in pyridine...pyridine π-stacking; steric hindrance between one C6H4PO(OEt)2 group and an adjacent pair of π-stacked pyridine rings results in distortion of backbone of the ligand. This report is the first crystallographic determination of a salt of a homoleptic [M{4′-(RO)2OPC6H4tpy}2]n+ cation.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Bakhmutov, Vladimir I., Douglas W. Elliott, Gregory P. Wylie, Abraham Clearfield, Aida Contreras-Ramirez e Hong-Cai Zhou. "Pyridine-d5 as a 2H NMR probe for investigation of macrostructure and pore shapes in a layered Sn(iv) phosphonate–phosphate material". Chemical Communications 56, n. 25 (2020): 3653–56. http://dx.doi.org/10.1039/c9cc09254d.

Testo completo

Abstract (sommario):

Isotropic and anisotropic motions and molecular states of pyridine-d₅, adsorbed on the surface within the pores of a layered Sn(iv) phosphonate–phosphate material (1) have been characterized thermodynamically and kinetically by solid-state NMR.

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Fard, Z. H., Y. Kalinovskyy, D. M. Spasyuk, B. A. Blight e G. K. H. Shimizu. "Alkaline-earth phosphonate MOFs with reversible hydration-dependent fluorescence". Chemical Communications 52, n. 87 (2016): 12865–68. http://dx.doi.org/10.1039/c6cc06490f.

Testo completo

Abstract (sommario):

A new rigid tritopic phosphonic ligand, 2,4,6-tris(4-phosphonophenyl)pyridine (H6L), was synthesized and used to assemble isostructural barium (1) and strontium (2) phosphonate metal organic frameworks that exhibit fully reversible and selective water-dependent fluorescence red-shift at room temperature.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Zangana, Karzan H., Eufemio Moreno Pineda e Richard E. P. Winpenny. "Tetrametallic lanthanide(iii) phosphonate cages: synthetic, structural and magnetic studies". Dalton Trans. 43, n. 45 (2014): 17101–7. http://dx.doi.org/10.1039/c4dt02630f.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Lipinski, Radoslaw, Longin Chruscinski, Piotr Mlynarz, Bogdan Boduszek e Henryk Kozlowski. "Coordination abilities of amino-phosphonate derivatives of pyridine". Inorganica Chimica Acta 322, n. 1-2 (ottobre 2001): 157–61. http://dx.doi.org/10.1016/s0020-1693(01)00580-1.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Frantz, Richard, Michel Granier, Jean-Olivier Durand e Gérard F. Lanneau. "Phosphonate derivatives of pyridine grafted onto oxide nanoparticles". Tetrahedron Letters 43, n. 50 (dicembre 2002): 9115–17. http://dx.doi.org/10.1016/s0040-4039(02)02240-2.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Holý, Antonín, e Ivan Rosenberg. "Synthesis of isomeric and enantiomeric O-phosphonylmethyl derivatives of 9-(2,3-dihydroxypropyl)adenine". Collection of Czechoslovak Chemical Communications 52, n. 11 (1987): 2775–91. http://dx.doi.org/10.1135/cccc19872775.

Testo completo

Abstract (sommario):

Reaction of 9-(S)-(2,3-dihydroxypropyl)adenine (I) with chloromethanephosphonyl chloride (VII) in pyridine or triethyl phosphate, or with chloromethyl(pyridinio)phosphonate (IX) in pyridine, afforded a mixture of 2'-(IV) and 3'-O-chloromethanephosphonate (V) which were separated on anion exchange resin or alkylsilica gel. Treatment of compounds IV and V with aqueous alkaline hydroxide, followed by deionization, gave 9-(S)-(2-hydroxy-3-phosphonylmethoxypropyl)adenine (VI) and 9-(S)-(3-hydroxy-2-phosphonylmethoxypropyl)adenine (III) (HPMPA), respectively. The (R)- and (RS)-forms of III and VI were prepared analogously from the respective (R)-enantiomer and racemate of I. 9-(S)-(2,3-Dihydroxypropyl)-N6-benzoyladenine (XIV) was converted into 3'-O-(dimethoxytrityl) derivative XVII and further into 2',N6-dibenzoyl derivative XIX. Reaction of compound XVII with IX, followed by acid hydrolysis and alkaline cyclization, afforded pure isomer VI whereas pure III was prepared from XIX by reaction with VII in triethyl phosphate and subsequent alkaline cyclization.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Wang, Cheng Jun, Shan Shan Gong e Qi Sun. "An H-Phosphonate Approach for the Preparation of Purine-Nucleoside Monophosphates". Advanced Materials Research 1023 (agosto 2014): 51–54. http://dx.doi.org/10.4028/www.scientific.net/amr.1023.51.

Testo completo

Abstract (sommario):

Two purine-nucleoside monophosphates have been prepared from the corresponding nucleoside 5′-H-phosphonate precursors via sequential silylation, oxidation, and hydrolysis reactions in a one-pot manner. Compared to the reaction performed in the presence of pyridine, the hydrolysis of iodophosphate in the absence of pyridine generated nucleoside 5′-monophosphates as the major product. The experimental results indicated that the reaction between the formed nucleoside 5′-monophosphate with the residual iodophosphate intermediate was relatively slow, making the self-condensed dinucleoside diphosphate a minor product in this reaction.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Sekine, Yoshihiro, Taiga Yokoyama, Norihisa Hoshino, Manabu Ishizaki, Katsuhiko Kanaizuka, Tomoyuki Akutagawa, Masa-aki Haga e Hitoshi Miyasaka. "Stepwise fabrication of donor/acceptor thin films with a charge-transfer molecular wire motif". Chemical Communications 52, n. 97 (2016): 13983–86. http://dx.doi.org/10.1039/c6cc08310b.

Testo completo

Abstract (sommario):

Novel thin films composed of a donor/acceptor charge-transfer chain compound were fabricated by a layer-by-layer technique using complexation of a paddlewheel-type [Ru₂^II,II] complex with a DCNQI derivative on an ITO substrate with a pyridine-substituted phosphonate anchor.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Zhang, Hui, Weiguo Cao, Qi Huang, Dong He, Jing Han, Jie Chen, Weimin He, Hongmei Deng e Min Shao. "[3+2] Cycloaddition of N-Aminopyridines and Perfluoroalkynylphosphonates: Facile Synthesis of Perfluoroalkylated Pyrazolo[1,5-a]pyridines Containing a Phosphonate Moiety". Synthesis 50, n. 18 (23 luglio 2018): 3731–37. http://dx.doi.org/10.1055/s-0037-1610443.

Testo completo

Abstract (sommario):

1,3-Zwitterions generated from N-aminopyridines in the presence of base are trapped by perfluoroalkynylphosphonates to yield a variety of perfluoroalkylated pyrazolo[1,5-a]pyridine derivatives bearing a phosphonate group. The salient features of these [3+2] cycloadditions include operational simplicity, good tolerance of functional groups, and good to excellent yields at room temperature.

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Frantz, Richard, Jean-Olivier Durand e Michel Granier. "Syntheses and properties of phosphonate π-conjugated of pyridine". Comptes Rendus Chimie 8, n. 5 (maggio 2005): 911–15. http://dx.doi.org/10.1016/j.crci.2004.10.016.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Wilk, Magdalena, Jan Janczak e Veneta Videnova-Adrabinska. "The supramolecular architecture of tris(naphthalene-1,5-diaminium) bis(5-aminonaphthalen-1-aminium) octakis[hydrogen (5-carboxypyridin-3-yl)phosphonate]". Acta Crystallographica Section C Crystal Structure Communications 68, n. 9 (4 agosto 2012): o351—o354. http://dx.doi.org/10.1107/s0108270112033781.

Testo completo

Abstract (sommario):

The asymmetric unit of the title compound, 3C10H12N22+·2C10H11N2+·8C6H5NO5P−, contains one and a half naphthalene-1,5-diaminium cations, in which the half-molecule has inversion symmetry, one 5-aminonaphthalen-1-aminium cation and four hydrogen (5-carboxypyridin-3-yl)phosphonate anions. The crystal structure is layered and consists of hydrogen-bonded anionic monolayers between which the cations are arranged. The acid monoanions are organized into one-dimensional chains along the [101] directionviahydrogen bonds established between the phosphonate sites. (C)O—H...Npyhydrogen bonds (py is pyridine) crosslink the chains to form an undulating (010) monolayer. The cations serve both to balance the charge of the anionic network and to connect neighbouring layersviamultiple hydrogen bonds to form a three-dimensional supramolecular architecture.

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Liu, Qian, e Richard F. Jordan. "Copolymerization of Ethylene and Vinyl Fluoride by Self-Assembled Multinuclear Palladium Catalysts". Polymers 12, n. 7 (19 luglio 2020): 1609. http://dx.doi.org/10.3390/polym12071609.

Testo completo

Abstract (sommario):

The self-assembled multinuclear PdII complexes {(Li-OPOOMe2)PdMe(4-5-nonyl-pyridine)}4Li2Cl2 (C, Li-OPOOMe2 = PPh(2-SO3Li-4,5-(OMe)2-Ph)(2-SO3−-4,5-(OMe)2-Me-Ph)), {(Zn-OP-P-SO)PdMe(L)}4 (D, L = pyridine or 4-tBu-pyridine, [OP-P-SO]3− = P(4-tBu-Ph)(2-PO32−-5-Me-Ph)(2-SO3−-5-Me-Ph)), and {(Zn-OP-P-SO)PdMe(pyridine)}3 (E) copolymerize ethylene and vinyl fluoride (VF) to linear copolymers. VF is incorporated at levels of 0.1–2.5 mol% primarily as in-chain -CH2CHFCH2- units. The molecular weight distributions of the copolymers produced by D and E are generally narrower than for catalyst C, which suggests that the Zn-phosphonate cores of D and E are more stable than the Li-sulfonate-chloride core of C under copolymerization conditions. The ethylene/VF copolymerization activities of C–E are over 100 times lower and the copolymer molecular weights (MWs) are reduced compared to the results for ethylene homopolymerization by these catalysts.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Sun, Jian, Shan Shan Gong e Qi Sun. "Efficient Synthesis of Pyrimidine-Nucleoside Monophosphates from H-Phosphonates". Advanced Materials Research 1023 (agosto 2014): 87–90. http://dx.doi.org/10.4028/www.scientific.net/amr.1023.87.

Testo completo

Abstract (sommario):

Two natural pyrimidine-nucleoside 5′-monophosphates have been synthesized from the corresponding nucleoside 5′-H-phosphonate monoesters via a one-pot reaction in high yields.31P NMR tracing experiments revealed that after H2O was added, iodophosphate intermediates were hydrolyzed immediately to generate nucleoside 5′-monophosphates almost quantitatively. Unlike the reaction in pyridine, the iodine oxidation reaction in DMF followed by immediate hydrolysis formed only a very small amount of dinucleoside diphosphate self-condensation byproduct.

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Chyba, Jan, Marek Necas e Jiri Pinkas. "Diethyl [4-(2,2′:6′,2′′-terpyridine-4′-yl)phenyl]phosphonate". Acta Crystallographica Section E Structure Reports Online 69, n. 12 (27 novembre 2013): o1824. http://dx.doi.org/10.1107/s1600536813031541.

Testo completo

Abstract (sommario):

The title compound, C25H24N3O3P, was obtained by catalytic phosphonation of 4′-(4-bromphenyl)-2,2′:6′,2′′-terpyridine. The terpyridine moiety is nearly planar, the dihedral angles between the central and the outer rings being 4.06 (9) and 5.39 (9)°. The N atoms in the two pyridine rings are oriented nearly antiperiplanar to that of the central ring. The benzene ring is rotated out of the plane of the central ring of the terpyridine unit by 34.65 (6)°.

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Bergkamp, Jesse J., Benjamin D. Sherman, Ernesto Mariño-Ochoa, Rodrigo E. Palacios, Gonzalo Cosa, Thomas A. Moore, Devens Gust e Ana L. Moore. "Synthesis and characterization of silicon phthalocyanines bearing axial phenoxyl groups for attachment to semiconducting metal oxides". Journal of Porphyrins and Phthalocyanines 15, n. 09n10 (settembre 2011): 943–50. http://dx.doi.org/10.1142/s1088424611003847.

Testo completo

Abstract (sommario):

A series of axial phenoxy substituted octabutoxy silicon phthalocyanines bearing ethyl carboxylic ester and diethyl phosphonate groups have been prepared from the corresponding phenols in pyridine. Axial bis-hydroxy silicon phthalocyanine was prepared using an adaptation of a reported protocol [1, 2] from the octabutoxy free-base phthalocyanine. The phenols bear either carboxylic ester or phosphonate groups, which upon deprotection can serve as anchoring groups for attaching the phthalocyanines to semiconducting metal oxides used in dye sensitized solar cells (DSSCs). All the phthalocyanines of the series absorb in the near infra-red region: 758–776 nm. The first oxidation potential for each phenoxy derivative occurs near 0.55 V vs. SCE as measured by cyclic voltammetry, with all falling within a 10 mV range. This indicates that these dyes will have sufficient energy in the photo-excited state to drive the reduction of protons to hydrogen. Taking into account the absorption and electrochemical potentials, these dyes are promising candidates for use in dual-threshold photo-electrochemical cells.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Airoldi, Annalisa, Piergiorgio Bettoni, Monica Donnola, Gianluca Calestani e Corrado Rizzoli. "Crystal structure of zwitterionic 3-(2-hydroxy-2-phosphonato-2-phosphonoethyl)imidazo[1,2-a]pyridin-1-ium monohydrate (minodronic acid monohydrate): a redetermination". Acta Crystallographica Section E Crystallographic Communications 71, n. 1 (1 gennaio 2015): 51–54. http://dx.doi.org/10.1107/s2056989014026863.

Testo completo

Abstract (sommario):

In a previous study, the X-ray structure of the title compound, C9H12N2O7P2·H2O, was reported [Takeuchiet al., (1998).Chem. Pharm. Bull.46, 1703–1709], but neither atomic coordinates nor details of the geometry were published. The structure has been redetermined with high precision as its detailed knowledge is essential to elucidate the presumed polymorphism of minodronic acid monohydrate at room temperature. The molecule crystallizes in a zwitterionic form with cationic imidazolium[1,2a]pyridine and anionic phosphonate groups. The dihedral angle formed by the planes of the pyridine and imidazole rings is 3.55 (9)°. A short intramolecular C—H...O contact is present. In the crystal, molecules are linked by O—H...O, N—H...O and C—H...O hydrogen bonds and π–π interactions [centroid-to-centroid distance = 3.5822 (11) Å], forming a three-dimensional structure.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Wilk, Magdalena, Jan Janczak e Veneta Videnova-Adrabinska. "Poly[aqua[μ3-(pyridin-1-ium-3,5-diyl)diphosphonato-κ3O:O′:O′′][μ2-(pyridin-1-ium-3,5-diyl)diphosphonato-κ2O:O′]calcium(II)]". Acta Crystallographica Section C Crystal Structure Communications 68, n. 2 (25 gennaio 2012): m41—m44. http://dx.doi.org/10.1107/s0108270112001461.

Testo completo

Abstract (sommario):

The rigid organic ligand (pyridine-3,5-diyl)diphosphonic acid has been used to create the title novel three-dimensional coordination polymer, [Ca(C5H6NO6P2)2(H2O)]n. The six-coordinate calcium ion is in a distorted octahedral environment, formed by five phosphonate O atoms from five different (pyridin-1-ium-3,5-diyl)diphosphonate ligands, two of which are unique, and one water O atom. Two crystallographically independent acid monoanions,L1 andL2, serve to link metal centres using two different coordination modes,viz.η2μ2and η3μ3, respectively. The latter ligand,L2, forms a strongly undulated two-dimensional framework parallel to the crystallographicbcplane, whereas the former ligand,L1, is utilized in the formation of one-dimensional helical chains in the [010] direction. The two sublattices ofL1 andL2 interweave at the Ca2+ions to form a three-dimensional framework. In addition, multiple O—H...O and N—H...O hydrogen bonds stabilize the three-dimensional coordination network. Topologically, the three-dimensional framework can be simplified as a very unusual (2,3,5)-connected three-nodal net represented by the Schläfli symbol (4·82)(4·88·10)(8).

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Kaur Bhatia, Richa. "Anti-Protozoal Potential of Heterocyclic Compounds Against Giardiasis". Current Bioactive Compounds 15, n. 3 (7 maggio 2019): 280–88. http://dx.doi.org/10.2174/1573407214666180201154009.

Testo completo

Abstract (sommario):

The aim of this literature review is to compile data of heterocyclic antigiardial agents. The importance is to analyze the structural requirements for improved antigiardial activity, to overcome resistance and enhance the bioavailability of the compounds under study. Though, nitroimidazoles/ imidazoles and benzimidazoles are major classes, other heterocyclic scaffolds viz. oxoindolinylidene, dioxodihydroisobenzofuran-5-carboxamide, fluoroquinolone, thieno[2,3-b]pyridine- 5-carbonitrile, α-amino-phosphonate analogs of polyoxins, nitazoxanide benzologue, thiazole and triazolyl- quinolone chalcone also possess activity against Giardia species. Heterocyclic phytoconstituents are also included to have a deep idea of antigiardial activity of herbs possessing heterocyclic constituents.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Tiwari, Shailee V., Aniket P. Sarkate, Deepak K. Lokwani, Dattatraya N. Pansare, Surendra G. Gattani, Sameer S. Sheaikh, Shirish P. Jain e Shashikant V. Bhandari. "Explorations of novel pyridine-pyrimidine hybrid phosphonate derivatives as aurora kinase inhibitors". Bioorganic & Medicinal Chemistry Letters 67 (luglio 2022): 128747. http://dx.doi.org/10.1016/j.bmcl.2022.128747.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Gielen, Marcel, Hassan Dalil, Laurent Ghys, Bogdan Boduszek, Edward R. T. Tiekink, José C. Martins, Monique Biesemans e Rudolph Willem. "Synthesis and Structure of Di-n-Butyltin Pyridine-2-phosphonate-6-carboxylate". Organometallics 17, n. 19 (settembre 1998): 4259–62. http://dx.doi.org/10.1021/om9803725.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Van hemel, Johan, Eddy L. Esmans, Pieter E. Joos, Alex De Groot, Roger A. Dommisse, Jan M. Balzarini e Erik D. De Clercq. "Synthesis and Biological Evaluation of Phosphonate Derivatives of Some Acyclic Pyridine-C-Nucleosides". Nucleosides and Nucleotides 17, n. 12 (dicembre 1998): 2429–43. http://dx.doi.org/10.1080/07328319808004329.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Hartwich, Anna, Nee Zdzienicka, Dominique Schols, Graciela Andrei, Robert Snoeck e Iwona E. Głowacka. "Design, synthesis and antiviral evaluation of novel acyclic phosphonate nucleotide analogs with triazolo[4,5-b]pyridine, imidazo[4,5-b]pyridine and imidazo[4,5-b]pyridin-2(3H)-one systems". Nucleosides, Nucleotides & Nucleic Acids 39, n. 4 (25 settembre 2019): 542–91. http://dx.doi.org/10.1080/15257770.2019.1669046.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Van hemel, Johan, Eddy L. Esmans, Pieter E. Joos, Alex De Groot, Roger A. Dommisse, Jan M. Balzarini e Erik D. De Clercq. "ChemInform Abstract: Synthesis and Biological Evaluation of Phosphonate Derivatives of Some Acyclic Pyridine-C-nucleosides." ChemInform 30, n. 16 (16 giugno 2010): no. http://dx.doi.org/10.1002/chin.199916236.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Gałęzowska, Joanna, Rafał Janicki, Henryk Kozłowski, Anna Mondry, Piotr Młynarz e Łukasz Szyrwiel. "Unusual Coordination Behaviour of a Phosphonate- and Pyridine-Containing Ligand in a Stable Lanthanide Complex". European Journal of Inorganic Chemistry 2010, n. 11 (13 marzo 2010): 1696–702. http://dx.doi.org/10.1002/ejic.201000058.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Fu, Ruibiao, Shengmin Hu e Xintao Wu. "Syntheses, structures, thermal stabilities and luminescence of two new lead sulfonates with phosphonate, carboxylate and pyridine". Journal of Solid State Chemistry 213 (maggio 2014): 17–21. http://dx.doi.org/10.1016/j.jssc.2014.01.028.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Balogh, Edina, Marta Mato-Iglesias, Carlos Platas-Iglesias, Éva Tóth, Kristina Djanashvili, Joop A. Peters, Andrés de Blas e Teresa Rodríguez-Blas. "Pyridine- and Phosphonate-Containing Ligands for Stable Ln Complexation. Extremely Fast Water Exchange on the GdIIIChelates". Inorganic Chemistry 45, n. 21 (ottobre 2006): 8719–28. http://dx.doi.org/10.1021/ic0604157.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Kovács, Attila, e Zoltán Varga. "Metal–ligand interactions in complexes of cyclen-based ligands with Bi and Ac". Structural Chemistry 32, n. 5 (18 agosto 2021): 1719–31. http://dx.doi.org/10.1007/s11224-021-01816-9.

Testo completo

Abstract (sommario):

AbstractThe structural and bonding properties of Bi and Ac complexes with cyclen-based chelating ligands have been studied using relativistic DFT calculations in conjunction with TZ2P all-electron basis sets. Besides the parent cyclen ligand, the study has covered its extensions with pyridine-type (Lpy), carboxylate (DOTA, DOTPA), picolinate (MeDO2PA) and phosphonate (DOTMP) pendant arms. The effect of the cyclen ring size has been probed by increasing it from [12]aneN4 to [16]aneN4. Additional extensions in the DOTA complexes included the H2O ligand at the 9th coordination site as well as the p-SCN-Bn substituent (a popular linker to the targeting vector). The study focuses on the complex stability, the nature of bonding and the differences between Ac and Bi in the complexes. The metal–ligand interactions have been analysed by the Extended Transition State method combined with Natural Orbitals of Chemical Valence theory and Quantum Theory of Atoms in Molecules models.

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Ho Lee, Phil, Kooyeon Lee, Jun Hwan Shim, Seong Guk Lee e Sundae Kim. "Regioselective Synthesis of 4-Alkylpyridines from Pyridine and Aldehydes via Dipole Reversal Process of 1,4-Dihydropyridine Phosphonate". HETEROCYCLES 67, n. 2 (2006): 777. http://dx.doi.org/10.3987/com-05-s(t)49.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Corbet, Matthieu, Michiel de Greef e Samir Z. Zard. "A Highly Conjunctive β-Keto Phosphonate: Application to the Synthesis of Pyridine Alkaloids Xestamines C, E, and H". Organic Letters 10, n. 2 (gennaio 2008): 253–56. http://dx.doi.org/10.1021/ol702590f.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Shih, Hao-Wei, Kuo-Ting Chen e Wei-Chieh Cheng. "One-pot synthesis of phosphate diesters and phosphonate monoesters via a combination of microwave-CCl3CN–pyridine coupling conditions". Tetrahedron Letters 53, n. 2 (gennaio 2012): 243–46. http://dx.doi.org/10.1016/j.tetlet.2011.11.032.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Holý, Antonín, Miloš Buděšínský, Jaroslav Podlaha e Ivana Císařová. "Synthesis of Quaternary 1-[2-(Phosphonomethoxy)ethyl] Derivatives of 2,4-Diaminopyrimidine and Related Acyclic Nucleotide Analogs". Collection of Czechoslovak Chemical Communications 64, n. 2 (1999): 242–56. http://dx.doi.org/10.1135/cccc19990242.

Testo completo

Abstract (sommario):

Quaternization of 2,4-diaminopyrimidine (2) by diisopropyl 2-chloroethoxymethanephosphonate (3) followed by bromotrimethylsilane treatment and subsequent hydrolysis gave zwitterionic N1-[2-(phosphonomethoxy)ethyl] derivative, hydrogen {[2-(2,4-diaminopyrimidin-1-io)ethoxy]methyl}phosphonate (5). Its structure was confirmed by X-ray crystallography. The same product was obtained from 2-amino-4-[(dimethylaminomethylene)amino]pyrimidine (6) by an analogous reaction sequence followed by an aqueous ammonia treatment after the transsilylation reaction. Also the quaternizations of 4,6-diaminopyrimidine (7) and 2,4,6-triaminopyrimidine (8) with the halo derivative 3 afforded the zwitterionic N1-substituted compounds 9 and 10, respectively. In contrast to this regiospecific reaction, 2-aminopyrimidine (11) gave on treatment with compound 3 and following deprotection the exo-N2-isomer 13. This compound was also obtained by the reaction starting from 2-[(dimethylaminomethylene)amino]pyrimidine (12) which was prepared by treatment of compound 11 with dimethylformamide dineopentyl acetal. Also 2,3-diaminopyridine (14) gave by the above reaction a mixture of 2-amino-3-{[2-(phosphonomethoxy)ethyl]amino}pyridine (15) and quaternary N1-[2-(phosphonomethoxy)ethyl] derivative (16). None of these analogs of the antiviral PMEDAP exhibited any antiviral activity against DNA viruses or retroviruses, nor any cytostatic activity.

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Murugavel, Ramaswamy, e Swaminathan Shanmugan. "Assembling metal phosphonates in the presence of monodentate-terminal and bidentate-bridging pyridine ligands. Use of non-covalent and covalent-coordinate interactions to build polymeric metal–phosphonate architectures". Dalton Transactions, n. 39 (2008): 5358. http://dx.doi.org/10.1039/b805848b.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Mato-Iglesias, Marta, Edina Balogh, Carlos Platas-Iglesias, Éva Tóth, Andrés de Blas e Teresa Rodríguez Blas. "Pyridine and phosphonate containing ligands for stable lanthanide complexation. An experimental and theoretical study to assess the solution structure". Dalton Trans., n. 45 (2006): 5404–15. http://dx.doi.org/10.1039/b611544f.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Hancock, Robert D., Arthur E. Martell, Dian Chen, Ramunas J. Motekaitis e Derek McManus. "Design of ligands for the complexation of Fe(II)/Fe(III) in the catalytic oxidation of H2S to sulfur". Canadian Journal of Chemistry 75, n. 5 (1 maggio 1997): 591–600. http://dx.doi.org/10.1139/v97-070.

Testo completo

Abstract (sommario):

Examination of the stability constants of Fe(II) and Fe(III) chelates of a wide variety of ligands that contain only acetate and amino groups shows a linear correlation. A separate linear correlation displaced toward the ferric ion was obtained for those ligands that contain more basic phenolate donor groups. The ligands of the latter group generally are unsuited to the oxidation of H2S to sulfur, while ligands in the first correlation are suitable for that purpose. Ligands that do not contain α-methylene groups are relatively resistant to oxidative degradation. Molecular mechanics is employed to compare the Fe(III) complexes of three such ligands, dipicolinic acid (DIPIC), pyridine-2-phosphonic-6-carboxylic acid (2PP6C), and 2-carboxy-8-hydroxyquinoline (CHOX). The calculations show that there is considerable strain in the formation of the Fe(II) and Fe(III) complexes of these ligands, both with respect to the O–O distance and the O-Fe-O angle. The relatively high stability of the CHOX complex compared to that of DIPIC, therefore, is due mainly to the higher basicity of the phenolate oxygen compared to the carboxylate groups of DIPIC. The higher stability of the Fe(III) complex of 2PP6C relative to that of DIPIC is due to the higher basicity and charge of the phosphonate group compared to a carboxylate group of DIPIC that it replaces. In spite of the lack of α-methylene groups in CHOX, the ligand undergoes rapid oxidative degradation when its iron chelate is used as a catalyst for the oxidation of H2S to sulfur by air. However, the oxidation products were found to also be effective catalysts for this process. Keywords: hydrogen sulfide, oxidation catalysis, dipicolinic acid, pyridine-2-phosphonic-6-carboyxlic acid, 2-carboxy-8-hydroxyquinoline.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Shih, Hao-Wei, Kuo-Ting Chen e Wei-Chieh Cheng. "ChemInform Abstract: One-Pot Synthesis of Phosphate Diesters and Phosphonate Monoesters via a Combination of Microwave-CCl3-Pyridine Coupling Conditions." ChemInform 43, n. 17 (29 marzo 2012): no. http://dx.doi.org/10.1002/chin.201217189.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Trofimov, Boris A., Pavel A. Volkov e Anton A. Telezhkin. "Electron-Deficient Acetylenes as Three-Modal Adjuvants in SNH Reaction of Pyridinoids with Phosphorus Nucleophiles". Molecules 26, n. 22 (11 novembre 2021): 6824. http://dx.doi.org/10.3390/molecules26226824.

Testo completo

Abstract (sommario):

Publications covering a new easy metal-free functionalization of pyridinoids (pyridines, quinolines, isoquinolines, acridine) under the action of the system of electron-deficient acetylenes (acetylenecarboxylic acid esters, acylacetylenes)/P-nucleophiles (phosphine chalcogenides, H-phosphonates) are reviewed. Special attention is focused on a SNH reaction of the regioselective cross-coupling of pyridines with secondary phosphine chalcogenides triggered by acylacetylenes to give 4-chalcogenophosphorylpyridines. In these processes, acetylenes act as three-modal adjuvants (i) activating the pyridine ring towards P-nucleophiles, (ii) deprotonating the P-H bond and (iii) facilitating the nucleophilic addition of the P-centered anion to a heterocyclic moiety followed by the release of the selectively reduced acetylenes (E-alkenes).

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Podstawka, Edyta, Tomasz K. Olszewski, Bogdan Boduszek e Leonard M. Proniewicz. "Adsorbed States of Phosphonate Derivatives ofN-Heterocyclic Aromatic Compounds, Imidazole, Thiazole, and Pyridine on Colloidal Silver: Comparison with a Silver Electrode". Journal of Physical Chemistry B 113, n. 35 (3 settembre 2009): 12013–18. http://dx.doi.org/10.1021/jp9050116.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Telezhkin, A. A., P. A. Volkov e K. O. Khrapova. "Nucleophilic substitution of hydrogen in pyridine and its derivatives by organophosphorus nucleophiles in the presence of electron-deficient acetylenes". Журнал органической химии 59, n. 10 (15 dicembre 2023): 1269–300. http://dx.doi.org/10.31857/s0514749223100026.

Testo completo

Abstract (sommario):

The review considers publications on a new easy functionalization of pyridinoids (pyridines, quinolines, isoquinolines, acridine, phenanthridine) by the electron-deficient acetylene (esters of acetylenecarboxylic acids, acylacetylenes, cyanoacetylenes)/P-nucleophile (phosphine chalcogenides, H -phosphonates) system. Particular attention is paid to the SN H reaction of regioselective cross-coupling of pyridines with secondary phosphine chalcogenides, initiated by acylacetylenes and leading to the formation of 4-chalcogenophosphorylpyridines. In these processes, acetylenes act as trimodal adjuvants by (1) activating the pyridine ring towards P-nucleophiles, (2) deprotonating the P-H bond, and (3) facilitating the nucleophilic addition of the P-centered anion to the heterocyclic fragment, followed by the release of selectively reduced (to E -alkenes) acetylenes.

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Drahoš, Bohuslav, Jan Kotek, Ivana Cı́sařová, Petr Hermann, Lothar Helm, Ivan Lukeš e Éva Tóth. "Mn2+Complexes with 12-Membered Pyridine Based Macrocycles Bearing Carboxylate or Phosphonate Pendant Arm: Crystallographic, Thermodynamic, Kinetic, Redox, and1H/17O Relaxation Studies". Inorganic Chemistry 50, n. 24 (19 dicembre 2011): 12785–801. http://dx.doi.org/10.1021/ic201935r.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Podstawka, Edyta, Andrzej Kudelski, Tomasz K. Olszewski e Bogdan Boduszek. "Surface-Enhanced Raman Scattering Studies on the Interaction of Phosphonate Derivatives of Imidazole, Thiazole, and Pyridine with a Silver Electrode in Aqueous Solution". Journal of Physical Chemistry B 113, n. 29 (23 luglio 2009): 10035–42. http://dx.doi.org/10.1021/jp902328j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Cummings, Charles Y., Jay D. Wadhawan, Takuya Nakabayashi, Masa-aki Haga, Liza Rassaei, Sara E. C. Dale, Simon Bending, Martin Pumera, Stephen C. Parker e Frank Marken. "Electron hopping rate measurements in ITO junctions: Charge diffusion in a layer-by-layer deposited ruthenium(II)-bis(benzimidazolyl)pyridine-phosphonate–TiO2 film". Journal of Electroanalytical Chemistry 657, n. 1-2 (luglio 2011): 196–201. http://dx.doi.org/10.1016/j.jelechem.2011.04.010.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Baba, Kazuaki, Kojiro Nagata, Tatsuo Yajima e Takashi Yoshimura. "Synthesis, Structures, and Equilibrium Reactions of La(III) and Ba(II) Complexes with Pyridine Phosphonate Pendant Arms on a Diaza-18-crown-6 Ether". Bulletin of the Chemical Society of Japan 95, n. 3 (15 marzo 2022): 466–75. http://dx.doi.org/10.1246/bcsj.20210414.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Kiefer, Garry E., e Mark Woods. "Solid State and Solution Dynamics of Pyridine Based Tetraaza-Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-PCTMB): Effect on Relaxometry and Optical Properties". Inorganic Chemistry 48, n. 24 (21 dicembre 2009): 11767–78. http://dx.doi.org/10.1021/ic901779k.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Philippov, Igor, Yuriy Gatilov, Alina Sonina e Aleksey Vorob’ev. "Oxidative [3+2]Cycloaddition of Alkynylphosphonates with Heterocyclic N-Imines: Synthesis of Pyrazolo[1,5-a]Pyridine-3-phosphonates". Molecules 27, n. 22 (16 novembre 2022): 7913. http://dx.doi.org/10.3390/molecules27227913.

Testo completo

Abstract (sommario):

A series of pyrazolo[1,5-a]pyridine-3-ylphosphonates were prepared with moderate to good yields by the oxidative [3+2]cycloaddition of 2-subtituted ethynylphosphonates with in situ generated pyridinium-N-imines and their annulated analogs. 2-Aliphatic and 2-Ph acetylenes demonstrate low activity, and the corresponding pyrazolopyridines were achieved with a moderate yield in the presence of 10 mol% Fe(NO3)3·9H2O. At the same time, tetraethyl ethynylbisphosphonate, diethyl 2-TMS- and 2-OPh-ethynylphosphonates possess much greater reactivity and the corresponding pyrazolo[1,5-a]pyridines, and their annulated derivatives were obtained with good to excellent yields without any catalyst. 2-Halogenated ethynylphosphonates also readily reacted with pyridinium-N-imines, forming complex mixtures containing poor amounts of 2-halogenated pyrazolopyridines.

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Sun, Kai, Xiao-Lan Chen, Xu Li, Ling-Bo Qu, Wen-Zhu Bi, Xi Chen, Hui-Li Ma et al. "H-phosphonate-mediated sulfonylation of heteroaromatic N-oxides: a mild and metal-free one-pot synthesis of 2-sulfonyl quinolines/pyridines". Chemical Communications 51, n. 60 (2015): 12111–14. http://dx.doi.org/10.1039/c5cc04484g.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Wilk-Kozubek, Magdalena, Katarzyna N. Jarzembska, Jan Janczak e Veneta Videnova-Adrabinska. "Synthesis, structural characterization and computational studies of catena-poly[chlorido[μ3-(pyridin-1-ium-3-yl)phosphonato-κ3 O:O′:O′′]zinc(II)]". Acta Crystallographica Section C Structural Chemistry 73, n. 5 (5 aprile 2017): 363–68. http://dx.doi.org/10.1107/s2053229617004478.

Testo completo

Abstract (sommario):

Coordination polymers are constructed from two basic components, namely metal ions, or metal-ion clusters, and bridging organic ligands. Their structures may also contain other auxiliary components, such as blocking ligands, counter-ions and nonbonding guest or template molecules. The choice or design of a suitable linker is essential. The new title zinc(II) coordination polymer, [Zn(C5H5NO3P)Cl] n , has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction and vibrational spectroscopy (FT–IR and FT–Raman). Additionally, computational methods have been applied to derive quantitative information about interactions present in the solid state. The compound crystallizes in the monoclinic space group C2/c. The four-coordinated ZnII cation is in a distorted tetrahedral environment, formed by three phosphonate O atoms from three different (pyridin-1-ium-3-yl)phosphonate ligands and one chloride anion. The ZnII ions are extended by phosphonate ligands to generate a ladder chain along the [001] direction. Adjacent ladders are held together via N—H...O hydrogen bonds and offset face-to-face π–π stacking interactions, forming a three-dimensional supramolecular network with channels. As calculated, the interaction energy between the neighbouring ladders is −115.2 kJ mol−1. In turn, the cohesive energy evaluated per asymmetric unit-equivalent fragment of a polymeric chain in the crystal structure is −205.4 kJ mol−1. This latter value reflects the numerous hydrogen bonds stabilizing the three-dimensional packing of the coordination chains.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Stawinski, J., R. Strömberg e E. Westman. "Ribonucleoside H-Phosphonates. Pyridine vs Quinoline - Influence on Condensation Rate". Nucleosides and Nucleotides 10, n. 1-3 (gennaio 1991): 519–20. http://dx.doi.org/10.1080/07328319108046514.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!