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  • 1.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Iodine-promoted silylation of alcohols with silyl chlorides. Synthetic and mechanistic studies2008Inngår i: Tetrahedron, ISSN 0040-4020, Vol. 64, nr 37, s. 8843-8850Artikkel i tidsskrift (Fagfellevurdert)
  • 2.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of nucleoside phosphorothio-, phosphorodithio- and phophoroselenoate diesters via oxidative esterification of the corresponding H-phosphonate analogues2008Inngår i: Collection Symposium Series, Vol. 10, 2008, s. 219-223Konferansepaper (Annet vitenskapelig)
  • 3.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The case for the intermediacy of monomeric metaphosphate analogues during oxidation of H-phosphonothioate, H-phosphonodithioate, and H-phosphonoselenoate monoesters: mechanistic and synthetic studies2008Inngår i: The Journal of Organic Chemistry, ISSN 0022-3263, Vol. 73, nr 13, s. 5029-5038Artikkel i tidsskrift (Fagfellevurdert)
  • 4. George, Riham F.
    et al.
    Ismail, Nasser S. M.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Girgis, Adel S.
    Design, synthesis and QSAR studies of dispiroindole derivatives as new antiproliferative agents2013Inngår i: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 68, s. 339-351Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A variety of 4'-ary1-3-(arylmethylidene)-1 ''-[(cyclic-amino)methylene]-1'-methyl-dispiro[cyclohexane-1,3'-pyrrolidine-2',3 ''-[3H]indole]-2,2 ''(1H)-diones 4a-u were prepared via reaction of 2E,6E-bis(arylidene)-1-cyclohexanones 1a-i with azomethine ylides, generated in situ via a decarboxylative condensation of isatins 2a-c and sarcosine (3). Single crystal X-ray study of 4a, revealed structural and stereochemical features of these derivatives. While most of the synthesized compounds exhibit mild antitumor properties when tested against various human tumor cell lines (HEPG2 liver, HELA cervical and PD prostate cancers), three of them, 4d and 4p (active against HEPG2), and compound 4g (active against HELA), demonstrated higher activities, that were close or even higher than that of the reference standard Doxorubicin. QSAR studies revealed good predictive and statistically significant 3 descriptor models (r(2) = 0.903-0.812, r(adjusted)(2) = 0.855-0.672, r(prediction)(2) = 0.773-0.605).

  • 5. Girgis, Adel S.
    et al.
    Mabied, Ahmed F.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hegazy, Lamees
    George, Riham F.
    Farag, Hanaa
    Shalaby, ElSayed M.
    Farag, I. S. Ahmed
    Synthesis and DFT studies of an antitumor active spiro-oxindole2015Inngår i: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 39, nr 10, s. 8017-8027Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An anti-oncological active spiro-oxindole 7 was synthesized regioselectively via a [3+2]-cycloaddition reaction of azomethine ylide to exocyclic olefinic linkage of 4-piperidone 6, exhibiting properties against diverse tumor cell lines including leukemia, melanoma and cancers of the lung, colon, brain, ovary, breast, prostate, and kidney. Compound 7 crystallizes in the monoclinic system and P21/c space group with four molecules in the unit cell. The structure was also studied by AM1, PM3 and DFT techniques. DFT studies support the stereochemical selectivity of the reaction and determine the molecular electrostatic potential and frontier molecular orbitals.

  • 6. Girgis, Adel S.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ismail, Nasser S. M.
    Farag, Hanaa
    Synthesis and QSAR study of novel cytotoxic spiro[3H-indole-3,2 '(1 ' H)-pyrrolo[3,4-c]pyrrole]-2,3 ',5 '(1H,2 ' aH,4 ' H)-triones2012Inngår i: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 47, s. 312-322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    1,3-Dipolar cycloaddition reaction of 1-aryl-1H-pyrrole-2,5-diones 1a-e with non-stabilized azomethine ylides, generated in situ via decarboxylative condensation of isatins 2a-c and sarcosine (3) in refluxing ethanol, afforded 4'-aryl-5'a,6'-dihydro-1'-methyl-spiro[3H-indole-3,2'(1 ' H)-pyrrolo[3,4-c]pyrrole]-2,3',5'(1H,2'aH,4'H)-triones 4a-o in good yields. Compound 4I exhibited high anti-tumor activity against HEPG2 (liver cancer) cell line (IC50 = 12.16 mu M) compared to that of Doxorubicin (IC50= 7.36 mu M), and the other synthesized compounds revealed moderate anti-tumor properties against HCT116 (colon), MCF7 (breast) and HEPG2 (liver) human tumor cell lines. 3D-Pharmacophore modeling and quantitative structure-activity relationship (QSAR) analysis were combined to explore the structural requirements controlling the observed anti-tumor properties. It was found that the major structural factors affecting potency of these compounds were related to their basic skeleton.

  • 7.
    Hiresova, Renata
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nucleoside H-phosphonates, XXII: Synthesis and properties of new nucleotide analogues - H-phosphonothiolate diesters2007Inngår i: Synlett, ISSN 0936-5214, nr 17, s. 2748-2752Artikkel i tidsskrift (Fagfellevurdert)
  • 8.
    Híresová, Renáta
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Studies on the condensation of H-phosphonate monoesters with S-Nucleophiles2007Inngår i: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Konferansepaper (Annet vitenskapelig)
  • 9. Ji, Sanhao
    et al.
    Ju, Yong
    Fu, Hua
    Zhao, Yufen
    Johansson, Tommy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The influences of a nitrogen atom position in dinucleoside 2-,3-,4-pyridylphosphonates on fragmentation patterns in electrospray ionization multistage tandem mass spectra2006Inngår i: Nucleosides, Nucleotides, and Nucleic Acids, ISSN 1525-7770, Vol. 25, s. 771-784Artikkel i tidsskrift (Fagfellevurdert)
  • 10.
    Jimenez-Halla, J. Oscar C.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Computational study of the mechanism and selectivity of palladium catalyzed propargylic substitution with phosphorus nucleophiles2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 39, s. 12424-12436Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mechanism and sources of selectivity in the palladium-catalyzed propargylic substitution reaction that involves phosphorus nucleophiles, and which yields predominantly allenylphosphonates and related compounds, have been studied computationally by means of density functional theory. Full free-energy profiles are computed for both H-phosphonate and H-phosphonothioate substrates. The calculations show that the special behavior of H-phosphonates among other heteroatom nucleophiles is indeed reflected in higher energy barriers for the attack on the central carbon atom of the allenyl/propargyl ligand relative to the ligand-exchange pathway, which leads to the experimentally observed products. It is argued that, to explain the preference of allenyl- versus propargyl-phosphonate/phosphonothioate formation in reactions that involve H-phosphonates and H-phosphonothioates, analysis of the complete free-energy surfaces is necessary, because the product ratio is determined by different transition states in the respective branches of the catalytic cycle. In addition, these transition states change in going from a H-phosphonate to a H-phosphonothioate nucleophile.

  • 11.
    Johansson, Tommy
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nucleoside H-phosphonates.: Part 19. Efficient entry to novel nucleotide analogues with 2-pyridyl and 4-pyridylphosphonothioate internucleotide linkages2004Inngår i: Tetrahedron, ISSN 0040-4020, Vol. 60, nr 2, s. 389-395Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Synthetic and 31P NMR spectroscopy studies resulted in the development of efficient protocols for the stereospecific synthesis of a novel type of nucleotide analogues, 2-pyridyl- and 4-pyridylphosphonothioates. The underlying chemistry involves formation of the P–C bond via a base-promoted reaction of suitably protected dithymidine H-phosphonothioates with N-methoxypyridinium tosylate in acetonitrile, or with trityl chloride in pyridine, to produce high yields of nucleotide analogues with a 2-pyridyl- or 4-pyridyl moiety directly bound to the phosphorus centre.

  • 12.
    Johansson, Tommy
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of Dinucleoside Pyridylphosphonates Involving Palladium(0)-catalysed Phosphorus-carbon Bond Formation as a Key Step2001Inngår i: Chemical Communications, ISSN 1359-7345, nr 24, s. 2564-2565Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dinucleoside 3-pyridylphosphonates, as well as their 2- and 4-pyridyl positional isomers, have been synthesised using a palladium(0)-catalysed cross coupling strategy

  • 13.
    Johansson, Tommy
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    The Case for Configurational Stability of H-Phosphonate Diesters in the Presence of Diazabicyclo[5.4.0]undec-7-ene (DBU)2001Inngår i: Bioorganic & Medicinal Chemistry, ISSN 0968-0896, Vol. 9, nr 9, s. 2315-2322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Configurational stability of dinucleoside H-phosphonates and the stereochemical course of their sulfurisation in the presence of diazabicyclo[5.4.0]undec-7-ene (DBU) were investigated using 31P NMR spectroscopy. It was found that under the reaction conditions and irrespective of the type of protecting groups present in the nucleoside moieties, the H-phosphonate diesters investigated did not undergo any detectable epimerisation at the phosphorus centre, and their sulfurisation with elemental sulfur in the presence of DBU, proceeded stereospecifically. Thus, we could not confirm reports from another laboratory on a stereoselective course of sulfurisation of H-phosphonate diesters and the corresponding acylphosphonates in the presence of DBU.

  • 14.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bartoszewicz, Agnieszka
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of nucleoside phosphorothio-, phosphorodithio- and phosphoroselenoate diesters via oxidative esterification of the corresponding H-phosphonate analogues2008Inngår i: Nucleic Acids Symposium Series, ISSN 0261-3166, Vol. 52, s. 285-286Artikkel i tidsskrift (Fagfellevurdert)
  • 15.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jezowska, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-catalyzed propargylic substitution with phosphorus nucleophiles2010Inngår i: Abstracts of Papers, 240th ACS National Meeting, Boston, MA, United States, August 22-26, 2010, Washington, D C: American Chemical Society , 2010Konferansepaper (Annet vitenskapelig)
  • 16.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jezowska, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Preparation of arylphosphonates by palladium(0)-catalyzed cross-coupling in the presence of acetate additives: Synthetic and mechanistic studies2009Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 351, nr 18, s. 3207-3216Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient protocol for the synthesis of arylphosphonate diesters via a palladium-catalyzed cross-coupling of H-phosphonate diesters with aryl electrophiles, promoted by acetate ions, was developed. A significant shortening of the cross-coupling time in the presence of the added acetate ions was achieved for bidentate and monodentate supporting ligands, and for different aryl electrophiles (iodo, bromo and triflate derivatives). The reaction conditions were optimized in terms of amount of the catalyst, supporting ligands, and source of the acetate ion used. Various arylphosphonates, including those of potential biological significance, were synthesized using this newly developed protocol. Some mechanistic aspects of the investigated reactions are also discussed.

  • 17.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Johansson, Tommy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jezowska, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-catalyzed propargylic substitution with phosphorus nucleophiles: efficient, stereoselective synthesis of allenylphosphonates and related compounds2010Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 12, nr 20, s. 4702-4704Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new, efficient method is developed, based on a palladium(0)-catalyzed reaction of propargylic derivatives with various phosphorus nucleophiles, to produce allenylphosphonates and their analogues with defined stereochemistry in the allenic and the phosphonate moiety. 

  • 18.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient synthesis of mono-and diarylphosphinic acids: a microwave-assisted palladium-catalyzed cross-coupling of aryl halides with phosphinate2009Inngår i: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 65, nr 50, s. 10406-10412Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A general, efficient method for the microwave-assisted synthesis of mono- and diarylphosphinic acids from anilinium phosphinate and aryl halides, using Pd(0) and Xantphos as a supporting ligand, was developed.

  • 19.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Novel, stereoselective and stereospecific synthesis of allenylphosphonates and related compounds via palladium-catalyzed propargylic substitution2011Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 353, nr 10, s. 1741-1755Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed a novel method for the synthesis of allenylphosphonates and related compounds based on a palladium(0)-catalyzed reaction of propargylic derivatives with H-phosphonate,H-phosphonothioate, H-phosphonoselenoate, and H-phosphinateesters. The reaction is stereoselective and stereospecific, and provides a convenient entry to a vast array of allenylphosphonates and their analogues with diverse substitution patterns in the allenic moiety and at the phosphorus center. Some mechanistic aspects of this new reaction were also investigated.

  • 20.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-catalyzed C-P bond formation: Mechanistic studies on the ligand substitution and the reductive elimination. An intramolecular catalysis by the acetate group in PdII complexes2008Inngår i: Organometallics, ISSN 0276-7333, E-ISSN 1520-6041, Vol. 27, nr 22, s. 5876-5888Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ligand substitution and reductive elimination of the palladium-catalyzed C−P bond forming cross-coupling were investigated in depth. It was found that for PhPdII(PPh3)2X (X = I, Br, Cl) complexes, a step commonly referred to as ligand substitution commenced with coordination of an H-phosphonate diester, followed by its deprotonation to form an equilibrium mixture of penta- and tetracoordinate palladiumphosphonate intermediates, from which reductive elimination of the product (diethyl phenylphosphonate) occurred. For the acetate counterpart, PhPdII(PPh3)2(OAc), the incorporation of a phosphonate moiety to the complex was preceded by a rate-determining removal of the supporting phosphine ligand, facilitated by an intramolecular catalysis by the acetate group. Both the reaction steps, i.e., formation of palladiumphosphonate intermediates and reductive elimination, were significantly faster for the acetate versus halides containing PdII complexes investigated. Similar observations were found to be true also for bidentate ligand complexes [(dppp)PdII(Ph)X]; however, in this instance, a single palladiumphosphonate intermediate, (dppp)PdII(Ph)(PO(OEt)2), could be observed by 31P NMR spectroscopy. The synthetic and kinetic studies on the cross-coupling reaction of diethyl H-phosphonate with phenyl halides permitted us to elucidate a crucial catalytic role of an acetate group in PdII complexes and to propose two distinctive catalytic cycles, which complemented traditional Pd0/PdII schemes, for the palladium-mediated C−P bond formation.

  • 21.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pd(0)-Catalyzed phosphorus-carbon bond formation: Mechanistic and synthetic studies on the role of the palladium sources and anionic additives2007Inngår i: Organometallics, ISSN 0276-7333, E-ISSN 1520-6041, Vol. 26, nr 24, s. 5840-5847Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pd(PPh3)4, Pd(dba)2, Pd(OAc)2, and PdCl2, have been evaluated as possible Pd(0) sources for the palladium-catalyzed P−C bond formation via a cross-coupling of aryl halides with H-phosphonate diesters. It was found that the most efficient catalytic system can be generated from Pd(OAc)2 with a key role being played by Pd(II) and Pd(0) species with coordinated acetate ions. The reactivity of differently ligated Pd(II) complexes was determined, and 31P NMR spectroscopy studies were carried out to provide mechanistic interpretations for the observed differences between the catalytic systems.

  • 22.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthetic studies on the P-C bond formation via a palladium-catalyzed cross-coupling reaction. Application to the synthesis of P-arylated nucleic acids2008Inngår i: Collection Symposium Series, Vol. 10, 2008, s. 214-218Konferansepaper (Annet vitenskapelig)
  • 23.
    Kalek, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ziadi, Asraa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Microwave-assisted palladium-catalyzed cross-coupling of aryl and vinyl halides with H-phosphonate diesters2008Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 10, nr 20, s. 4637-4640Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A general and efficient method for the microwave-assisted formation of the C−P bond was developed. Using a prevalent palladium catalyst, Pd(PPh3)4, a quantitative cross-coupling of various H-phosphonate diesters with aryl and vinyl halides was achieved in less than 10 min. The reactions occurred with retention of configuration at the phosphorus center and in the vinyl moiety. Using this protocol, several C-phosphonates, including those bearing nucleoside and cholesteryl moieties, were prepared in high yields.

  • 24. Kraszewski, Adam
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    H-Phosphonates: versatile synthetic precursors to biologically active phosphorus compounds2007Inngår i: Pure and Applied Chemistry, ISSN 0033-4545, Vol. 79, nr 12, s. 2217-2227Artikkel i tidsskrift (Fagfellevurdert)
  • 25.
    Kullberg, Martin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Preparation of nucleoside H-phosphonoselenoate monoesters via the phosphinate approach2005Inngår i: Nucleosides, Nucleotides & Nucleic Acids, ISSN 1525-7770, E-ISSN 1532-2335, Vol. 24, nr 10-12, s. 1627-1633Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient entry to nucleoside 3'-H-phosphonoselenoate monoesters via phosphinate intermediates was developed. It involves a reaction of suitably protected nucleosides with triethylammonium phosphinate in the presence of pivaloyl chloride, followed by selenization of the intermediate nucleoside phosphinates with triphenylphosphine selenide, to produce the corresponding nucleoside H-phosphonoselenoates in 86-92% yields.

  • 26.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jezowska, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Preparation of benzylphosphonates via a palladium(0)-catalyzed cross-coupling of H-phosphonate diesters with benzyl halides. Synthetic and mechanistic studies2010Inngår i: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 34, nr 5, s. 967-975Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed a new, efficient method for the synthesis of benzylphosphonate andbenzylphosphonothioate diesters via a palladium(0)-catalyzed cross-coupling reaction betweenbenzyl halides and H-phosphonate or H-phosphonothioate diesters, using Pd2(dba)3(CHCl3)as a palladium source and Xantphos as a supporting ligand. Some mechanistic aspects of thesereactions were investigated using 31P NMR spectroscopy.

  • 27.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nilsson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Silylation-Mediated Transesterification of Phenyl H-Phosphonothioate: A New Entry to Nucleoside H-Phosphonothioate Monoesters2004Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 24, s. 5111-5114Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    O-Phenyl H-phosphonothioate undergoes a facile transesterification with suitably protected nucleosides upon in situ silylation with tert-butyldiphenylsilyl chloride in pyridine/toluene to produce the corresponding 3'-H-phosphonothioates in good yields. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).

  • 28.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A new synthetic route to diastereomerically pure P-chiral nucleotide analogues, dinucleoside benzylphosphonates, via stereospecific Pd(0) catalyzed cross-coupling reaction2008Inngår i: Collection Symposium Series, Vol. 10, 2008, s. 395-397Konferansepaper (Annet vitenskapelig)
  • 29.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium(0)-catalyzed benzylation of H-phosphonate diesters: An efficient entry to benzylphosphonates2009Inngår i: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, nr 2, s. 225-228Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new, efficient method for the synthesis of benzylphosphonate diesters via a palladium(0)-catalyzed cross-coupling reaction between benzyl halides and H-phosphonate diesters, using Pd(OAc)2 as a palladium source and Xantphos as a supporting ligand, has been developed.

  • 30.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthetic Studies on the Preparation of Dinucleoside Phenyl-Phosphonates and Phenyl-Phosphonothioates via Palladium(0) Catalyzed Cross-Coupling2005Inngår i: / [ed] Michal Hocek, 2005, s. 195-199Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Separate diastereomers of protected dithymidine (3'-5')-phenylphosphonates and dithymidine (3'-5')phenylphosphonothioate were obtained via a palladium(0) catalysed stereo-specific cross-coupling reaction of separate diastereomers of corresponding dinucleoside H-phosphonate and dinucleoside H-phosphonothioate with halobenzenes.

  • 31.
    Lavén, Gaston
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthetic studies on the preparation of nucleoside 5'-H-phosphonate monoesters under the Mitsunobu reaction conditions2009Inngår i: ARKIVOC, ISSN 1424-6376, nr 3, s. 20-27Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A reaction of suitably protected nucleosides with phosphonic acid in the presence of diethyl azodicarboxylate and triphenylphosphine in pyridine provided in good yields the corresponding 5’-H-phosphonate monoesters.

  • 32.
    Nilsson, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    Institute of Bioorganic Chemistry, Polish Academy of Science.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chemical and Stereochemical Aspects of Oxidative Coupling of H Phosphonantes and H-Phosphonothioate Diesters: Reactions with N,N-, N,O- and O,O-Binucleophiles2005Inngår i: Letters in organic chemistry, ISSN 1570-1786, Vol. 2, nr 2, s. 188-197Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Efficient protocols for oxidative coupling of dinucleoside H-phosphonate and dinucleoside Hphosphonothioate diesters with 6-aminohexan-1-ol, hexane-1,6-diamine, and hexane-1,6-diol, promoted by iodine were developed. In the instance of coupling with O-nucleophiles, the presence of t-butyldiphenylsilyl chloride and excess of iodine during oxidative coupling were found to have beneficial effect for these reactions in terms of rates and purity of the formed products

  • 33.
    Nilsson, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Controlling Stereochemistry During Oxidative Coupling: Preparation of Rp or Sp Phosphoramidates from One P-Chiral Precursor2004Inngår i: Chemical Communications, ISSN 1359-7345, Vol. 22, s. 2566-2567Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stereochemical outcome of oxidative coupling of H-phosphonate diesters with amines, promoted by iodine, can be controlled to obtain the corresponding phosphoramidate diesters with inversion or with retention of configuration at the phosphorus centre

  • 34.
    Nilsson, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Oxidative Coupling of H-Phosphonate and H-Phosphonothioate Diesters: Iodine as a Reagent and a Catalyst2002Inngår i: Collection Symposium Series, Vol. 5, s. 87-92Artikkel i tidsskrift (Fagfellevurdert)
  • 35. Sobczak, Milena
    et al.
    Johansson, Tommy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bulkowski, Marek
    Sochacki, Marek
    Lavén, Gaston
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mikolaczyk, Barbara
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Polish Academy of Sciences, Poland.
    Nawrot, Barbara
    Dna oligonucleotides with stereodefined phenylphosphonate and phosphonothioate internucleotide bonds: synthesis and physico chemical properties2012Inngår i: ARKIVOC, ISSN 1551-7004, E-ISSN 1551-7012, nr 4, s. 63-79Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Separate diastereomers of suitably protected dithymidine (3',5')-phenylphosphonates and dithymidine (3',5')-phenylphosphonothioates were obtained via a palladium(0) catalysed stereospecific cross-coupling reaction between separate diastereomers of the corresponding dinucleoside H-phosphonates and dinucleoside H-phosphonothioates with iodobenzene. These compounds were converted into the corresponding phosphoramidite building blocks and used for incorporation of P-stereodefined dithymidine phenylphosphonate and phenylphosphonothioate units TxT into DNA oligonucleotide chain. Dodecathymidylates with centrally positioned one (T(9)TxTT(9)) or two modified units (T(8)TxTTxTT(8)) exhibited different affinity towards complementary DNA (dA(20)) or RNA (A(20)) strands depending on stereochemistry at the phosphorus center, as determined by UV melting temperature studies. Oligonucleotides containing the R-P-phenylphosphonate or R-P -phenylphosphonothioate internucleotide linkages exhibited higher binding affinity to the complementary strands than their S-P-counterparts, but slightly lower than the non-modified reference T-20. All phenylphosphonothioate-modified oligonucleotides formed less stable than their oxo-counterparts duplexes. As expected, the cleavage of the oligonucleotides investigated with 3'- and 5'-exonucleases was stalled at the modification site, independently of P-chirality at the modification site.

  • 36. Sobkowski, Michal
    et al.
    Kraszewski, Adam
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stereochemistry of internucleotide bond formation by the H-phosphonate method. Part 3: Investigations on a mechanism of asymmetric induction2007Inngår i: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 18, nr 19, s. 2336-2348Artikkel i tidsskrift (Fagfellevurdert)
  • 37. Sobkowski, Michal
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    A convenient stereochemical notation for P-chiral nucleotide analogs2007Inngår i: Current Protocols in Nucleic Acid Chemistry, Vol. Supplement 28, s. A.1E.1-A.1E.16Artikkel i tidsskrift (Fagfellevurdert)
  • 38. Sobkowski, Michal
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    A proposal for a convenient notation for P-chiral nucleotide analogues. Part 4. A relationship between the DP/LP notation and stereochemistry of reactions2009Inngår i: Nucleosides, Nucleotides & Nucleic Acids, ISSN 1525-7770, E-ISSN 1532-2335, Vol. 28, nr 1, s. 29-42Artikkel i tidsskrift (Fagfellevurdert)
  • 39. Sobkowski, Michal
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    Stereochemistry of internucleotide bond formation by the H-phosphonate method. 7. Stereoselective formation of ribonucleoside (R-P)- and (S-P)-3 '-H-phosphonothioate monoesters2010Inngår i: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 21, nr 4, s. 410-419Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ribonucleoside 3'-H-phosphonothioate monoesters exist in the form of (R-P)- and (S-P)-diastereomers. In order to obtain them in good yields and in high stereochemical purity, stereoselective strategies for their preparation were investigated. For the synthesis of the (R-P)-isomer, a stereoselective sulfhydrolysis of an activated nucleoside H-phosphonate was developed, while the monoesters with an (S-P)-configuration were prepared by asymmetric transformation of diastereomeric mixtures of nucleoside 3'-H-phosphonothioates using either a condensation with 9-fluorenemethanol, followed by beta-elimination, or via pivaloylation-hydrolysis reaction sequence. A tentative assignment of the absolute configurations of the obtained diastereomers of 3'-H-phosphonothioate esters was carried out via a stereochemical correlation analysis.

  • 40. Sobkowski, Michal
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    Stereochemistry of internucleotide bond formation by the H-phosphonate method. Part 6: Optimization of the reaction conditions towards highest stereoselectivity2008Inngår i: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 19, nr 21, s. 2508-2518Artikkel i tidsskrift (Fagfellevurdert)
  • 41. Sobkowski, Michal
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    The role of nucleophilic catalysis in chemistry and stereochemistry of ribonucleoside H-phosphonate condensation2009Inngår i: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 33, nr 1, s. 164-170Artikkel i tidsskrift (Fagfellevurdert)
  • 42. Sobkowski, Michał
    et al.
    Jankowska, Jadwiga
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kraszewski, Adam
    Unusual stereochemistry of esterification of uridine 3'-H-phosphonothioate2011Inngår i: Phosphorus Sulfur and Silicon and the Related Elements, ISSN 1042-6507, E-ISSN 1563-5325, Vol. 186, nr 4, s. 952-955Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    According to 31P-NMR correlation analysis, reactive derivatives of uridine 3'-H-phosphonothioatereact with O-nucleophiles, probably with retention of configuration.

  • 43. Stamatov, Stephan D.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Direct trifluoroacetylation across a trimethylsilyloxy system as a stereospecific, chemo- and regioselective approach to C3-vicinal halohydrins2007Inngår i: Synlett, nr 3, s. 439-442Artikkel i tidsskrift (Fagfellevurdert)
  • 44. Stamatov, Stephan D.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    O-Silylated C3-halohydrins as a novel class of protected building blocks for total, regio- and stereocontrolled synthesis of glycerolipid frameworks2010Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 8, nr 2, s. 463-477Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    We propose O-silylated C3-halohydrins [1(3)-O-silyl-2-O-acyl-, 1,2(2,3)-O-bis(silyl)-, and 1(3)-O-acyl-2-O-silyl-3(1)-halo-sn-glycerides] as new chirons in the total synthesis of glycerolipid constructs. These are efficiently producible via opening of the oxirane ring of the corresponding glycidyl derivatives and permit (i) displacement of the iodine by a requisite carboxylate in the presence of O-triisopropylsilyl (O-TIPS), O-tert-butyldimethylsilyl (O-TBDMS), and O-acyl substituents; (ii) selective acylation across an appropriate silyloxy system [e. g., O-TBDMS or O-triethylsilyl (O-TES)] of monoesterified haloglycerides; (iii) direct exchange of an O-silyl protection (e. g., O-TBDMS or O-TIPS) for a trichloroacetyl group; (iv) conversion of a terminal TBDMS group into the corresponding trifluoroacetate without affecting O-TIPS-, O-acyl- and iodo functions. The above transformations secure flexible routes to a variety of otherwise difficult-to-access key-intermediates [e.g., 1,2(2,3)-O-bis(acyl)-3(1)-trichloroacetyl-, 1,3-O-bis(acyl)-2-trichloroacetyl-, 1,2(2,3)-O-bis(acyl)-3(1)-O-TBDMS/TIPS-, 1,3-O-bis(acyl)-2-O-TIPS/TBDMS-, 1(3)-O-acyl-2-O-TIPS-, 1,2(2,3)-O-bis(acyl)-3(1)-iodo-sn-glycerols, etc.] and lend themselves to a powerful methodology for the preparation of di- and triacylglycerols as well as glycerol-based cationic lipids. The reactions involved are entirely regio- and stereospecific, avoid acyl migration, and can provide target compounds with a chosen absolute configuration from a single synthetic precursor.

  • 45. Stamatov, Stephan D.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Regioselective and stereospecific acylation across oxirane- and silyloxy systems as a novel strategy to the synthesis of enantiomerically pure mono-, di- and triglycerides2007Inngår i: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 5, s. 3787-3800Artikkel i tidsskrift (Fagfellevurdert)
  • 46. Stamatov, Stephan D.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Regioselective and stereospecific halosilylating cleavage of the oxirane system of glycidol derivatives as an efficient strategy to C2-O-functionalized C3-vicinal halohydrins2008Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, nr 15, s. 2635-2643Artikkel i tidsskrift (Fagfellevurdert)
  • 47.
    Söderberg, Linda
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Laven, Gaston
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    (31)P NMR AND COMPUTATIONAL STUDIES ON STEREOCHEMISTRY OF CONVERSION OF PHOSPHORAMIDATE DIESTERS INTO THE CORRESPONDING PHOSPHOTRIESTERS2011Inngår i: Nucleosides, Nucleotides & Nucleic Acids, ISSN 1525-7770, E-ISSN 1532-2335, Vol. 30, nr 7-9, s. 552-564Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    (31)P NMR spectroscopy was used to investigate a stereochemical course of a nitrite-promoted conversion of phosphoramidate diesters into the corresponding phosphotriesters. It was found that this reaction occurred with almost complete epimerization at the phosphorus center and at the C1 atom in the amine moiety. On the basis of the (31)P NMR data, a plausible mechanism for the reaction was proposed. The density functional theory calculation of the key step of the reaction, i.e., breaking of the P-N bond and formation of the P-O bond, suggested a one-step S(N)2(P) process with retention of configuration at the phosphorus center.

  • 48.
    Wallin, Richard
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bartoszewicz, Agnieszka
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Thelin, Mats
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    On the sulfurization of H-phosphonate diesters and phosphite triesters using elemental sulfur2009Inngår i: Phosphorus Sulfur and Silicon and the Related Elements, ISSN 1042-6507, E-ISSN 1563-5325, Vol. 184, nr 4, s. 908-916Artikkel i tidsskrift (Fagfellevurdert)
  • 49.
    Zmudzka, Katarzyna
    et al.
    Polish Acad Sci, Ctr Mol & Macromol Studies.
    Johansson, Tommy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wojcik, Marzena
    Polish Acad Sci, Ctr Mol & Macromol Studies.
    Janicka, Magdalena
    Polish Acad Sci, Ctr Mol & Macromol Studies.
    Nowak, Marian
    Polish Acad Sci, Ctr Mol & Macromol Studies.
    Stawinski, Jacek
    Nawrot, Barbara
    Polish Acad Sci, Ctr Mol & Macromol Studies.
    Novel DNA Analogues with 2-, 3- and 4-Pyridylphosphonate Internucleotide Bonds: Synthesis and Hybridisation Properties2003Inngår i: New Journal of Chemistry, ISSN 1144-0546, Vol. 27, nr 12, s. 1698-1705Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Oligothymidylates modified with stereodefined 2-pyridyl-, 3-pyridyl- and 4-pyridylphosphonate moieties at one or two juxtaposed internucleotide positions were prepared, and their avidity towards complementary single stranded DNA and RNA, as well as toward double stranded DNA were evaluated by UV melting temperature and CD studies. It was found that the sense of chirality at the phosphorus centre and the position of the nitrogen atom in the pyridyl ring of a pyridylphosphonate moiety are important factors governing stability of double- and triple-stranded complexes formed by these oligonucleotides. DNA/DNA and DNA/RNA duplexes containing oligothymidylate strands with R-P-pyridylphosphonate units differed only slightly from unmodified reference complexes. In contrast to this, the S-P-pyridylphosphonate derivatives exhibited lower binding affinity than both their R-P-counterparts and the unmodified reference oligonucleotide T-20. Triplexes of oligo(thymidyl pyridylphosphonate)s with hairpin oligomer d(A(21)C(4)T(21)) were found mostly to be thermodynamically slightly more stable in pH 7.4 and less stable in pH 5.0 than non-modified complexes. As expected, oligonucleotides with pyridylphosphonate internucleotide bonds were recognised by 3'- and 5'-exonucleases but the chimeric oligonucleotide chains were not cleaved at the modi. cation sites.

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