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  • 1. Alonso, D A
    et al.
    Bertilsson, S K
    Johnsson, S Y
    Nordin, S J M
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Södergren, M J
    Andersson, Pher G
    New Expidient Route to Both Enantiomers of Nonproteinogenic Amino Acid Derivatives from the Unsaturated 2-Aza-bicyclo Moiety. D. A1999Ingår i: J. Org. Chem., Vol. 64, s. 2276-Artikel i tidskrift (Refereegranskat)
  • 2. Alonso, D A
    et al.
    Nordin, S J M
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Andersson, Pher G
    Highly Diastereoselective Reaction of 2-Azanorbornyl Enolates with Electrophiles. D. A1999Ingår i: Org. Lett., Vol. 1, s. 1595-Artikel i tidskrift (Refereegranskat)
  • 3. Alonso, D A
    et al.
    Nordin, S J M
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Roth, P
    Tarnai, T
    Thommen, M
    Pittelkow, U
    Andersson, Pher G
    2-Azanorbornyl alcohols: Very efficient Ligands for Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of Aromatic Ketones. D. A1999Ingår i: J. Org. Chem., Vol. 65, s. 3116-Artikel i tidskrift (Refereegranskat)
  • 4.
    Alonso, Diego A
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Brandt, P
    Nordin, Sofia J M
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Andersson, Pher G
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Ru(arene)(amino alcohol)-Catalyzed Transfer Hydrogenation of Ketones: Mechanism and Origin of Enantioselectivity1999Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 121, nr 41, s. 9580-9588Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The mechanism of the Ru(arene)(amino alcohol)-catalyzed transfer hydrogenation of ketones using isopropyl alcohol as the hydrogen source has been studied by means of hybrid density functional methods (B3PW91). Three mechanistic alternatives were evaluated, and it was shown that the reaction takes place via a six-membered transition state, where a metal-bound hydride and a proton of a coordinated amine are transferred simultaneously to the ketone. Further calculations provided a general rationale for the rate of the reaction by comparison of steric effects in the ground and transition states of the ruthenium hydride complex. It was found that the TS has a strong preference for planarity, and this in turn is dependent on the conformational behavior of the O,N-linkage of the amino alcohol ligand. Finally, a general model, rationalizing the enantioselectivity of the reaction, was developed. Experimental studies of both rate and enantioselectivity were used in order to support the computational results.

  • 5.
    Arnaud, Gayet
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Christelle, Bolea
    Pher G., Andersson
    Development of new camphor based N,S chiral ligands and their application in transfer hydrogenation2004Ingår i: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 2, nr 13, s. 1887-1893Artikel i tidskrift (Refereegranskat)
  • 6.
    Arnaud, Gayet
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Sophie, Bertilsson
    Pher G., Andersson
    Novel Catalytic Kinetic Resolution Of Racemic Epoxides to Allylic alcohols2002Ingår i: Organic Letters, ISSN 1523-7060, Vol. 4, nr 22, s. 3777-3779Artikel i tidskrift (Refereegranskat)
  • 7.
    Bergman, Jan
    et al.
    CNT, DEPT ORGAN CHEM, S-14157 HUDDINGE, SWEDEN .
    Lidgren, Göran
    ROYAL INST TECHNOL, DEPT ORGAN CHEM, S-10044 STOCKHOLM 70, SWEDEN.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Synthesis and Reactions of Oxazolones from L‑Tryptophan and α‑Haloacetic Anhydrides1992Ingår i: Bulletin des Sociétés chimiques belges, ISSN 0037-9646, Vol. 101, nr 7, s. 643-660Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Optically active 5(4H)-oxazolones have been synthesized from L-tryptophan and an excess of trifluoro-, trichloro-, and dichloroacetic anhydrides. Some of the 5(4H)-xazolones have been further transformed to the isomeric 5(2H)-oxazolones as well as oxazolones with exocyclic double bonds. Treatment of the various oxazolones under hydrolytic, acidic and Friedel-Crafts acylation conditions gave indole-3-pyruvic acid, alpha,beta-dehydrotryptophans, beta-carbolines as well as the functionalized cyclopentanoindole 32. Treatment of the 4-(3-indolylmethyl)-2-trifluoromethyl-5(2H)-oxazolone (17) with trifluoroacetic acid gave the 3,4-bridged azepinoindole 35.

  • 8.
    Bergström, Sara K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Edenwall, Niklas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Lavén, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Velikyan, Irina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Markides, Karin E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Polyamine deactivation of integrated poly(dimethylsiloxane) structures investigated by radionuclide imaging and capillary electrophoresis experiments2005Ingår i: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 77, nr 3, s. 938-942Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The poly(dimethylsiloxane) (PDMS) material provides a number of advantageous features, such as flexibility, elasticity, and transparency, making it useful in integrated analytical systems. Hard fused-silica capillary structures and soft PDMS channels can easily be combined by a tight fit, which offers many alternatives for structure combinations. PDMS and fused silica are in different ways prone to adsorption of low levels of organic compounds. The need for modification of the inner wall surface of PDMS channels may often be necessary, and in this paper, we describe an easy and effective method using the amine-containing polymer PolyE-323 to deactivate both fused-silica and PDMS surfaces. The adsorption of selected peptides to untreated surfaces was compared to PolyE-323-modified surfaces, using both radionuclide imaging and capillary electrophoresis experiments. The polyamine modification displayed a substantially reduced adsorption of three hydrophobic test peptides compared to the native PDMS surface. Filling and storage of aqueous solution were also possible in PolyE-323-modified PDMS channels. In addition, hybrid microstructures of fused silica and PDMS could simultaneously be deactivated in one simple coating procedure.

  • 9. Berlin, Stefan
    et al.
    Ericsson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Engman, Lars
    Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization2002Ingår i: Organic Letters, Vol. 4, s. 3-Artikel i tidskrift (Refereegranskat)
  • 10. Berlin, Stefan
    et al.
    Ericsson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Engman, Lars
    Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones2003Ingår i: Journal of Organic Chemistry, Vol. 68, s. 8386-Artikel i tidskrift (Refereegranskat)
  • 11.
    Beşev, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Radical Cyclization Approaches to Pyrrolidines2002Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Five-membered rings are readily prepared by 5-exo-trig radical cyclization. This thesis is concerned with novel methodology for pyrrolidine synthesis. We have synthesised selenium containing radical precursors from aziridines and α-phenylseleno ketones, and cyclized them to 2,4- and 3,4-disubstituted pyrrolidines. A few examples of 5-exo-dig cyclization were also demonstrated. In another study we investigated the capacity of the nitrogen protecting group to direct diastereoselectivity in the formation of 2,4-disubstituted pyrrolidines. The diphenylphosphinoyl protecting group directed cyclization to occur in a highly cis-selective manner. When cyclizations were performed at 17 oC, cis/trans-ratios as high as 24/1 were obtained. In contrast, cyclization of the unprotected pyrrolidine precursor afforded the trans-diastereomer as the major product (cis/trans = 1/3.3 – 1/20). We also examined the use of a hydroxyl auxiliary for controlling diastereoselectivity in radical cyclization. The required selenium containing radical precursors were synthesised from 2-cyanoaziridines by addition of organometallic reagents, reduction of the resulting aziridine ketone, and benzeneselenol ring-opening of the aziridine. Cyclization at 17 oC produced 2,4-disubstituted pyrrolidines substantially enriched in the trans-isomer (cis/trans = 1/9 – 1/12). Novel radical cyclization approaches to thiazolines and pyrrolines were also tried.

    The thesis also describes attempts to improve the Hassner aziridine synthesis by employing stannous chloride as a functional group tolerant reducing agent.

  • 12.
    Bäckvall, Jan-Erling
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Andersson, Pher
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Stone, Guy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Syntheses of (±)-α- and (±)- γ- Lycorane via a Stereocontrolled Organopalladium Route1991Ingår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 56, nr 9, s. 2988-2993Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Total syntheses of (+/-)-alpha-and (+/-)-gamma-lycorane are described. The key steps in the syntheses are the stereocontrolled palladium-catalyzed intramolecular 1,4-chloroamidation of 12 to 13 and the subsequent anti-stereoselective copper-catalyzed S(N)2' reaction of allylic chloride 13 with [3,4-(methylenedioxy)phenyl]magnesium bromide to give 14. Hexahydroindole 14 has the required relative stereochemistry between carbons 3a, 7, and 7a for alpha-lycorane (1a) and was transformed to the latter via 15 and 16. The epimeric gamma-lycorane (2) was obtained by performing the Bischler-Napieralski cyclization on 14, which led to a highly stereoselective isomerization to give exclusively 17. Compound 17 was subsequently transformed to 2. The overall yield from ester 8 to (+/-)-alpha- and (+/-)-gamma-lycorane was 40 and 36%, respectively.

  • 13. Büttner, Frank
    et al.
    Norgren, Anna S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Zhang, Suode
    Prabpai, Samran
    Kongsaeree, Palangpon
    Arvidsson, Per I.
    Cyclic β-tetra- and pentapeptides: Synthesis through on-resin cyclization and conformational studies by X-ray, NMR and CD spectroscopy and theoretical calculations2005Ingår i: Chemistry--A European Journal, ISSN 0947-6539, Vol. 11, nr 21, s. 6145-6158Artikel i tidskrift (Refereegranskat)
  • 14.
    Diesen, Jarle Sidney
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Asymmetric Hydrogenations of Imines, Vinyl Fluorides, Enol Phosphinates and Other Alkenes Using N,P-Ligated Iridium Complexes2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The research described in this thesis is directed toward the efficient, enantioselective synthesis of chiral products that have useful functionality. This goal was pursued through catalytic asymmetric hydrogenation, a reaction class that selectively introduces one or two stereocenters into a molecule in an atom-efficient step. This reaction uses a small amount (often <1 mol%) of a chiral catalyst to impart stereoselectivity to the product formed. Though catalytic asymmetric hydrogenation is not a new reaction type, there remain many substrate classes for which it is ineffective. The present thesis describes efforts to extend the reaction to some of these substrates classes. Some of the products synthesized in these studies may eventually find use as building blocks for the production of chiral pharmaceuticals, agrochemicals, or flavouring or colouring agents. However, the primary and immediate aim of this thesis was to develop and demonstrate new catalysts that are rapid and effective in the asymmetric hydrogenation of a broad range of compounds.

    Paper I describes the design and construction of two new, related chiral iridium compounds that are catalysts for asymmetric hydrogenation. They each contain an N,P-donating phosphinooxazoline ligand that is held together by a rigid bicyclic unit. One of these iridium compounds catalyzed the asymmetric hydrogenation of acyclic aryl imines, often with very good enantioselectivities. This is particularly notable because acyclic imines are difficult to reduce with useful enantioselectivity. The second catalyst was useful for the asymmetric hydrogenation of two aryl olefins. In Paper II, the class of catalysts introduced into Paper I is expanded to include many more related compounds, and these are also applied to the asymmetric hydrogenation of prochiral imines and olefins. By studying a range of related catalysts that differ in a single attribute, we were able to probe how different parts of the catalyst affect the yield and selectivity of the hydrogenation reactions.

    Whereas iridium catalysts had been applied to the asymmetric hydrogenation of imines and largely unfunctionalized olefins prior to this work (with varied degrees of success), they had not been used to reduce fluoroolefins. Their hydrogenation, which is discussed in Paper III, was complicated by concomitant defluorination to yield non-halogenated alkanes. To combat this problem, several iridium-based hydrogenation catalysts were applied to the reaction. Two catalysts stood out for their ability to produce chiral fluoroalkanes in good enantioselectivity while minimizing the defluorination reaction, and one of these bore a phosphinooxazoline ligand of the type described in Papers I and II.

    Enol phosphinates are another class of olefins that had not previously been subjected to iridium-catalyzed asymmetric hydrogenation. They do, however, constitute an attractive substrate class, because the product chiral alkyl phosphinates can be transformed into chiral alcohols or chiral phosphines with no erosion of enantiopurity. Iridium complexes of the phosphinooxazoline ligands described in Papers I and II were extremely effective catalysts for the asymmetric hydrogenation of enol phosphinates. They produced alkyl phosphinates from di- and trisubstituted enol phosphinate, β-ketoester-derived enol phosphinates, and even purely alkyl-substituted enol phopshinates, in very high yields and enantioselectivities.

    Delarbeten
    1. Application of Phosphine-Oxazoline Ligands in Ir-Catalyzed Asymmetric Hydrogenation of Acyclic Aromatic N-Arylimines
    Öppna denna publikation i ny flik eller fönster >>Application of Phosphine-Oxazoline Ligands in Ir-Catalyzed Asymmetric Hydrogenation of Acyclic Aromatic N-Arylimines
    2004 Ingår i: Organic Letters, Vol. 6, nr 21, s. 3825-3827Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-97350 (URN)
    Tillgänglig från: 2008-05-13 Skapad: 2008-05-13Bibliografiskt granskad
    2. Hydrogenation of Imines and Olefins Using Phosphine-Oxazoline Iridium Complexes as Catalysts
    Öppna denna publikation i ny flik eller fönster >>Hydrogenation of Imines and Olefins Using Phosphine-Oxazoline Iridium Complexes as Catalysts
    2006 Ingår i: Chemistry-A European Journal, Vol. 12, nr 8, s. 2318-2328Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-97351 (URN)
    Tillgänglig från: 2008-05-13 Skapad: 2008-05-13Bibliografiskt granskad
    3. Iridium-Catalyzed Asymmetric Hydrogenation of Fluorinated Olefins Using N,P-Ligands: A struggle with hydrogenolysis and selectivity
    Öppna denna publikation i ny flik eller fönster >>Iridium-Catalyzed Asymmetric Hydrogenation of Fluorinated Olefins Using N,P-Ligands: A struggle with hydrogenolysis and selectivity
    2007 (Engelska)Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 129, nr 15, s. 4536-4537Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    To broaden the substrate scope of asymmetric iridium-catalyzed hydrogenation, fluorine-functionalized olefins were synthesized and hydrogenated with iridium complexes. Preliminary results showed high levels of fluorine elimination together with low selectivity. The loss of vinylic fluorine at first seemed difficult to handle, but further studies revealed that a catalyst with an azanorbornyl scaffold in the ligand gave more promising results. With this in mind, a new ligand was developed. This gave among the best results published to date for fluorine asymmetric hydrogenation, yielding high conversion and very high ee's with very little fluorine elimination. Further increasing the selectivity, the trials also revealed that tetrasubstituted fluorine-containing olefins can be hydrogenated with high ee's, despite that this class of compounds has usually shown low reactivity in this reaction type.

    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-97352 (URN)10.1021/ja0686763 (DOI)000245739700016 ()17375924 (PubMedID)
    Tillgänglig från: 2008-05-13 Skapad: 2008-05-13 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    4. Asymmetric Hydrogenation of Di and Trisubstituted Enol Phosphinates with N,P-Ligated Iridium Complexes
    Öppna denna publikation i ny flik eller fönster >>Asymmetric Hydrogenation of Di and Trisubstituted Enol Phosphinates with N,P-Ligated Iridium Complexes
    2008 (Engelska)Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 130, nr 16, s. 5595-5599Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The iridium-catalyzed asymmetric hydrogenation of various di- and trisubstituted enol phosphinates has been studied. Excellent enantioselectivities (up to >99% ee) and full conversion were observed for a range of substrates with both aromatic and aliphatic side chains. Enol phosphinates are structural analogues of enol acetates, and the hydrogenated alkyl phosphinate products can easily be transformed into the corresponding alcohols with conservation of stereochemistry. We have also hydrogenated, in excellent ee, several purely alkyl-substituted enol phosphinates, producing chiral alcohols that are difficult to obtain highly enantioselectively from ketone hydrogenations.

    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-97722 (URN)10.1021/ja711372c (DOI)000255041400050 ()
    Tillgänglig från: 2008-11-11 Skapad: 2008-11-11 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
  • 15. El-Sayed, Ibrahim
    et al.
    Guliashvili, Tamaz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Hazell, Rita
    Gogoll, Adolf
    Ottosson, Henrik
    Evidence for Formation of Silenes Strongly Influenced by Reversed Si=C Bond Polarity2002Ingår i: Organic Letters, ISSN 1523-7060, Vol. 4, nr 11, s. 1915-1918Artikel i tidskrift (Refereegranskat)
  • 16.
    Engman, Lars
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Al-Maharik, Nawaf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    McNaughton, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Birmingham, A
    Uppsala universitet.
    Powis, G.
    Uppsala universitet.
    Thioredoxin Reductase and Cancer Cell Growth Inhibition by Organotellurium Compounds that could be Selectively Incorporated into Tumor Cells2003Ingår i: Bioorganic & Medicinal Chemistry, ISSN 0968-0896, E-ISSN 1464-3391, Vol. 11, nr 23, s. 5091-5100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The thioredoxins are small ubiquitous redox proteins with the conserved redox catalytic sequence-Trp-Cys-Gly-Pro-Cys-Lys, where the Cys residues undergo reversible NADPH dependent reduction by selenocysteine containing flavoprotein thioredoxin reductases. Thioredoxin expression is increased in several human primary cancers including lung, colon, cervix, liver, pancreatic, colorectal and squamous cell cancer. The thioredoxin/thioredoxin reductase pathway therefore provides an attractive target for cancer drug development. Organotellurium steroid, lipid, amino acid, nucleic base, and polyamine inhibitors were synthesized on the basis that they might be selectively or differentially incorporated into tumor cells. Some of the newly prepared classes of tellurium-based inhibitors (lipid-like compounds 3b and 3e, amino acid derivative 5b, nucleic base derivative 8b, and polyamine derivatives 14a and 14b) inhibited TrxR/Trx and cancer cell growth in culture with IC(50) values in the low micromolar range.

  • 17.
    Engman, Lars
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    McNaughton, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Gajewska, Malgorzata
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Kumar, Sangit
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Birmingham, Anne
    Powis, Garth
    Thioredoxin reductase and cancer cell growth inhibition by organogold(III) compounds2006Ingår i: Anti-Cancer Drugs, ISSN 0959-4973, E-ISSN 1473-5741, Vol. 17, nr 5, s. 539-544Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thioredoxin (Trx) expression is increased in several human primary cancers associated with aggressive tumor growth and decreased patient survival, and the Trx/Trx reductase (TrxR) system therefore provides an attractive target for cancer drug development. Various gold(III) compounds with none, one, two or three carbon-gold bonds were evaluated for their capacity to inhibit TrxR and the growth of MCF-7 cancer cells in vitro. Compounds with up to two carbon-gold bonds were often potent inhibitors of TrxR with IC50 values as low as 2 nmol/l. In the presence of Trx and insulin the inhibiting capacity was much lower. However, the inhibitory concentrations of the compounds did not correlate with the ability to kill cells. Out of the organometallics tested, only compound 8 with two carbon-gold bonds was able to inhibit colony formation by MCF-7 breast cancer cells at low micromolar concentrations (IC50=1,6umol/l). Unfortunately, the compound did not show any anti-tumor activity against MCF-7 breast cancer and HT-29 colon cancer zenografts in scid mice.

  • 18.
    Erdélyi, Máté
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Towards the Development of Photoswitchable β-Hairpin Mimetics2004Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Peptide secondary structure mimetics are important tools in medicinal chemistry, as they provide analogues of endogeneous peptides with new physicochemical and pharmacological properties. The β-hairpin motif has been shown to be involved in numerous physiological processes, among others in regulation of eucariotic gene transcription. This thesis addresses the design, synthesis and conformational analysis of photoswitchable β-hairpin mimetics.

    The developmental work included the establishment of an improved procedure for cross coupling of aryl halides with terminal alkynes. Microwave mediated Sonogashira couplings in closed vessels were optimized under homogeneous and solid-phase conditions furnishing excellent yields for a large variety of substrates within 5 – 25 minutes. In addition, microwave heating was shown not to have any non-conventional effect on the reaction rate.

    Furthermore, the most important factors affecting β-hairpin stability were evaluated. Studies of tetrapeptide and decapeptide analogues revealed the essential role of the β-turn in initiation of hairpin folding. Moreover, hydrogen bonding was shown to be the main interchain stabilizing force, whereas hydrophobic interactions were found to be relatively weak. Nevertheless, hydrophobic packing appears to provide an important contribution to the thermodynamic stability of β-hairpins.

    Photoswitchable peptidomimetics were prepared by incorporation of various stilbene moieties into tetra- and decapeptides. Synthesis, photochemical isomerisation and spectroscopic conformational analysis of the compounds were performed.

    Delarbeten
    1. Rapid Homogeneous-Phase Sonogashira Coupling Reactions Using Controlled Microwave Heating
    Öppna denna publikation i ny flik eller fönster >>Rapid Homogeneous-Phase Sonogashira Coupling Reactions Using Controlled Microwave Heating
    2001 Ingår i: Journal of Organic Chemistry, Vol. 66, nr 12, s. 4165-4169Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-91463 (URN)
    Tillgänglig från: 2004-03-11 Skapad: 2004-03-11Bibliografiskt granskad
    2. Rapid Microwave Promoted Sonogashira Coupling Reactions on Solid Phase
    Öppna denna publikation i ny flik eller fönster >>Rapid Microwave Promoted Sonogashira Coupling Reactions on Solid Phase
    2003 (Engelska)Ingår i: Journal of Organic Chemistry, Vol. 68, nr 16, s. 6431-6434Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A microwave-enhanced, rapid, and efficient solidphase version of the Sonogashira reaction is presented. It has been applied to the coupling of aryl iodides and bromides with various acetylene derivatives giving excellent yields in 15 to 25 min. The scopes of homogeneous, solventless, and solid-phase conditions for Sonogashira coupling of aryl halides are compared.

    Nationell ämneskategori
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-91464 (URN)10.1021/jo034284s (DOI)
    Tillgänglig från: 2004-03-11 Skapad: 2004-03-11 Senast uppdaterad: 2011-01-05
    3. Insight into β-Hairpin Stability: A Structural and Thermodynamic Study of Diastereomeric β-Hairpin Mimetics
    Öppna denna publikation i ny flik eller fönster >>Insight into β-Hairpin Stability: A Structural and Thermodynamic Study of Diastereomeric β-Hairpin Mimetics
    2002 Ingår i: New Journal of Chemistry, Vol. 26, s. 834-843Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-91465 (URN)
    Tillgänglig från: 2004-03-11 Skapad: 2004-03-11Bibliografiskt granskad
    4. Synthesis and Conformational Analysis of Novel Stibene-type Peptidomimetics
    Öppna denna publikation i ny flik eller fönster >>Synthesis and Conformational Analysis of Novel Stibene-type Peptidomimetics
    Visa övriga...
    Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-91466 (URN)
    Tillgänglig från: 2004-03-11 Skapad: 2004-03-11Bibliografiskt granskad
    5. Synthesis and Conformational Analysis of Novel β-Hairpin mimetics. Factors Affecting Stability and Incorporation of a Photoswitchable Dipeptide Mimic
    Öppna denna publikation i ny flik eller fönster >>Synthesis and Conformational Analysis of Novel β-Hairpin mimetics. Factors Affecting Stability and Incorporation of a Photoswitchable Dipeptide Mimic
    Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-91467 (URN)
    Tillgänglig från: 2004-03-11 Skapad: 2004-03-11Bibliografiskt granskad
  • 19.
    Erdélyi, Máté
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Gogoll, Adolf
    Rapid Homogeneous-Phase Sonogashira Coupling Reactions Using Controlled Microwave Heating2001Ingår i: Journal of Organic Chemistry, Vol. 66, nr 12, s. 4165-4169Artikel i tidskrift (Refereegranskat)
  • 20.
    Erdélyi, Máté
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Gogoll, Adolf
    Rapid Microwave Promoted Sonogashira Coupling Reactions on Solid Phase2003Ingår i: Journal of Organic Chemistry, Vol. 68, nr 16, s. 6431-6434Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A microwave-enhanced, rapid, and efficient solidphase version of the Sonogashira reaction is presented. It has been applied to the coupling of aryl iodides and bromides with various acetylene derivatives giving excellent yields in 15 to 25 min. The scopes of homogeneous, solventless, and solid-phase conditions for Sonogashira coupling of aryl halides are compared.

  • 21.
    Erdélyi, Máté
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Langer, Vratislav
    Karlén, Anders
    Gogoll, Adolf
    Insight into β-Hairpin Stability: A Structural and Thermodynamic Study of Diastereomeric β-Hairpin Mimetics2002Ingår i: New Journal of Chemistry, Vol. 26, s. 834-843Artikel i tidskrift (Refereegranskat)
  • 22.
    Erdélyi, Máté
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Nurbo, Johanna
    Niklason, Ida
    Karlén, Anders
    Gogoll, Adolf
    Synthesis and Conformational Analysis of Novel Stibene-type PeptidomimeticsArtikel i tidskrift (Refereegranskat)
  • 23.
    Erdélyi, Máté
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Persson, Åsa
    Karlén, Anders
    Gogoll, Adolf
    Synthesis and Conformational Analysis of Novel β-Hairpin mimetics. Factors Affecting Stability and Incorporation of a Photoswitchable Dipeptide MimicArtikel i tidskrift (Refereegranskat)
  • 24.
    Ericsson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Synthesis of Tetrahydrofuran and Pyrrolidine Derivatives Utilising Radical Reactions: Organochalcogenides in Reductive, Carbonylative and Group-Transfer Cyclisation2004Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes free-radical reactions for the construction of tetrahydrofuran and pyrrolidine derivatives. The studies are concerned with (i) diastereoselectivity in radical cyclisation, (ii) construction of tetrahydrofuran-3-ones and pyrrolidin-3-ones via radical carbonylation/cyclisation and (iii) synthesis of tetrahydrofuran derivatives via group-transfer cyclisation of organochalcogen compounds.

    (i) Diastereoselectivity in the synthesis of tetrahydrofuran derivatives via radical cyclisation was controlled by addition of Lewis acids. In the synthesis of 2,4-disubstitued tetrahydrofurans, the trans-isomer was formed as the major product in the unperturbed reaction. Upon addition of trialkylalumiums the diastereoselectivity was reversed. In a similar fashion, exo/endo-diastereoselectivity in the synthesis of bicyclic 2,3,4-trisubstituted tetrahydrofurans could also be controlled.

    (ii) Procedures for construction of tetrahydrofuran-3-ones and pyrrolidin-3-ones were presented. Epoxides were ring-opened with benzeneselenolate or benzenetellurolate and the resulting β-hydroxyalkyl phenyl chalcogenides were vinylated using ethyl propiolate/NMM or E-1,2-bis(phenylsulfonyl)ethylene/NaH. The corresponding nitrogen analogues were accessed by N-vinylation of aziridines followed by benzeneselenolate ring-opening. The two types of organochalcogen radical precursors were then treated with TTMSS/AIBN under an atmosphere of carbon monoxide (80 atm) to afford tetrahydrofuran-3-ones and pyrrolidin-3-ones, respectively, in high yields.

    (iii) Microwaves were found to induce group-transfer cyclisation of β-allyloxyalkyl aryl chalcogenides. Short time heating (3-10 min) at 250 oC in ethylene glycol was required to obtain tetrahydrofuran derivatives in 60-91% yield.

    Delarbeten
    1. Diastereocontrol by Trialkylaluminums in the Synthesis of Tetrahydrofurans via Radical Cyclisation
    Öppna denna publikation i ny flik eller fönster >>Diastereocontrol by Trialkylaluminums in the Synthesis of Tetrahydrofurans via Radical Cyclisation
    2001 Ingår i: Organic Letters, Vol. 3, s. 3459-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-91437 (URN)
    Tillgänglig från: 2004-02-26 Skapad: 2004-02-26Bibliografiskt granskad
    2. Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    Öppna denna publikation i ny flik eller fönster >>Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    2002 Ingår i: Organic Letters, Vol. 4, s. 3-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-91438 (URN)
    Tillgänglig från: 2004-02-26 Skapad: 2004-02-26Bibliografiskt granskad
    3. Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones
    Öppna denna publikation i ny flik eller fönster >>Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones
    2003 Ingår i: Journal of Organic Chemistry, Vol. 68, s. 8386-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-91439 (URN)
    Tillgänglig från: 2004-02-26 Skapad: 2004-02-26Bibliografiskt granskad
    4. Microwave-Assisted Group-Transfer Cyclisation of Organotellurium Compounds
    Öppna denna publikation i ny flik eller fönster >>Microwave-Assisted Group-Transfer Cyclisation of Organotellurium Compounds
    Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-91440 (URN)
    Tillgänglig från: 2004-02-26 Skapad: 2004-02-26Bibliografiskt granskad
  • 25.
    Ericsson, Cecilia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Engman, Lars
    Diastereocontrol by Trialkylaluminums in the Synthesis of Tetrahydrofurans via Radical Cyclisation2001Ingår i: Organic Letters, Vol. 3, s. 3459-Artikel i tidskrift (Refereegranskat)
  • 26.
    Ericsson, Cecilia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Engman, Lars
    Microwave-Assisted Group-Transfer Cyclisation of Organotellurium CompoundsArtikel i tidskrift (Refereegranskat)
  • 27.
    Eriksson, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Synthesis of 11C-labelled Alkyl Iodides: Using Non-thermal Plasma and Palladium-mediated Carbonylation Methods2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Compounds labelled with 11C (β+, t1/2 = 20.4 min) are used in positron emission tomography (PET), which is a quantitative non-invasive molecular imaging technique. It utilizes computerized reconstruction methods to produce time-resolved images of the radioactivity distribution in living subjects.

    The feasibility of preparing [11C]methyl iodide from [11C]methane and iodine via a single pass through a non-thermal plasma reactor was explored. [11C]Methyl iodide with a specific radioactivity of 412 ± 32 GBq/µmol was obtained in 13 ± 3% decay-corrected radiochemical yield within 6 min via catalytic hydrogenation of [11C]carbon dioxide (24 GBq) and subsequent iodination, induced by electron impact.

    Labelled ethyl-, propyl- and butyl iodide was synthesized, within 15 min, via palladium-mediated carbonylation using [11C]carbon monoxide. The carbonylation products, labelled carboxylic acids, esters and aldehydes, were reduced to their corresponding alcohols and converted to alkyl iodides. [1-11C]Ethyl iodide was obtained via palladium-mediated carbonylation of methyl iodide with a decay-corrected radiochemical yield of 55 ± 5%. [1-11C]Propyl iodide and [1-11C]butyl iodide were synthesized via the hydroformylation of ethene and propene with decay-corrected radiochemical yields of 58 ± 4% and 34 ± 2%, respectively. [1-11C]Ethyl iodide was obtained with a specific radioactivity of 84 GBq/mmol from 10 GBq of [11C]carbon monoxide. [1-11C]Propyl iodide was synthesized with a specific radioactivity of 270 GBq/mmol from 12 GBq and [1-11C]butyl iodide with 146 GBq/mmol from 8 GBq.

    Palladium-mediated hydroxycarbonylation of acetylene was used in the synthesis of [1-11C]acrylic acid. The labelled carboxylic acid was converted to its acid chloride and subsequently treated with amine to yield N-[carbonyl-11C]benzylacrylamide. In an alternative method, [carbonyl-11C]acrylamides were synthesized in decay-corrected radiochemical yields up to 81% via palladium-mediated carbonylative cross-coupling of vinyl halides and amines. Starting from 10 ± 0.5 GBq of [11C]carbon monoxide, N-[carbonyl-11C]benzylacrylamide was obtained in 4 min with a specific radioactivity of 330 ± 4 GBq/µmol.

    Delarbeten
    1. [C-11]methyl iodide from [C-11]methane and iodine using a non-thermal plasma method
    Öppna denna publikation i ny flik eller fönster >>[C-11]methyl iodide from [C-11]methane and iodine using a non-thermal plasma method
    2006 (Engelska)Ingår i: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 49, nr 13, s. 1177-1186Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A method and an apparatus for preparing [C-11]methyl iodide from [C-11]methane and iodine in a single pass through a non-thermal plasma reactor has been developed. The plasma was created by applying high voltage (400 V/31 kHz) to electrodes in a stream of helium gas at reduced pressure. The [C-11]methane used in the experiments was produced from [C-11]carbon dioxide via reduction with hydrogen over nickel. [C-11]methyl iodide was obtained with a specific radioactivity of 412 +/- 32 GBq/mu mol within 6 min from approximately 24 GBq of [C-11]carbon dioxide. The decay corrected radiochemical yield was 13 +/- 3% based on [C-11]carbon dioxide at start of synthesis. [C-11]Flumazenil was synthesized via a N-alkylation with the prepared [C-11]methyl iodide.

    Nyckelord
    [C-11]methyl iodide, [C-11]methane, non-thermal plasma, specific radioactivity
    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-94929 (URN)10.1002/jlcr.1135 (DOI)000242796700006 ()
    Tillgänglig från: 2006-10-05 Skapad: 2006-10-05 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    2. Synthesis of [1-11C]ethyl iodide from carbon monoxide and its application in alkylation reactions
    Öppna denna publikation i ny flik eller fönster >>Synthesis of [1-11C]ethyl iodide from carbon monoxide and its application in alkylation reactions
    2004 (Engelska)Ingår i: Journal of Labelled Compounds and Radiopharmaceuticals, ISSN 0362-4803, Vol. 47, nr 11, s. 723-731Artikel i tidskrift (Refereegranskat) Published
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-94930 (URN)
    Tillgänglig från: 2006-10-05 Skapad: 2006-10-05 Senast uppdaterad: 2015-09-24
    3. Synthesis of [1-C-11]propyl and [1-C-11]butyl iodide from [C-11]carbon monoxide and their use in alkylation reactions
    Öppna denna publikation i ny flik eller fönster >>Synthesis of [1-C-11]propyl and [1-C-11]butyl iodide from [C-11]carbon monoxide and their use in alkylation reactions
    2006 (Engelska)Ingår i: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 49, nr 12, s. 1105-1116Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A method to prepare [1-C-11]propyl iodide and [1-C-11]butyl iodide from [C-11]carbon monoxide via a three step reaction sequence is presented. Palladium mediated formylation of ethene with [C-11]carbon monoxide and hydrogen gave [1-C-11]propionaldehyde and [1-C-11]propionic acid. The carbonylation products were reduced and subsequently converted to [1-C-11]propyl iodide. Labelled propyl iodide was obtained in 58 +/- 4% decay corrected radiochemical yield and with a specific radioactivity of 270 +/- 33 GBq/mu mol within 15 min from approximately 12 GBq of [C-11]carbon monoxide. The position of the label was confirmed by C-13-labelling and C-13-NMR analysis. [1-C-11]Butyl iodide was obtained correspondingly from propene and approximately 8 GBq of [C-11]carbon monoxide, in 34 +/- 2% decay corrected radiochemical yield and with a specific radioactivity of 146 +/- 20 GBq/mu mol. The alkyl iodides were used in model reactions to synthesize [O-propyl-1-C-11]propyl and [O-butyl-1-C-11]butyl benzoate. Propyl and butyl analogues of etomidate, a (beta-11-hydroxylase inhibitor, were also synthesized.

    Nyckelord
    [C-11]carbon monoxide, [1-C-11]propyl iodide, [1-C-11]butyl iodide, carbonylation, formylation, alkylation
    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-94931 (URN)10.1002/jlcr.1119 (DOI)000242335900009 ()
    Tillgänglig från: 2006-10-05 Skapad: 2006-10-05 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    4. Synthesis of [11C]/[13C]acrylamides by palladium-mediated carbonylation
    Öppna denna publikation i ny flik eller fönster >>Synthesis of [11C]/[13C]acrylamides by palladium-mediated carbonylation
    2007 (Engelska)Ingår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 3, s. 455-461Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Two methods are presented for the synthesis of acrylamides labelled with C-11 (beta(+), t(1/2) = 20.4 min) and C-11 in the carbonyl position. In the first method, [1-C-11]acrylic acid is synthesised from [C-11]carbon monoxide by palladium-mediated hydroxy-carbonylation of acetylene. The labelled carboxylic acid is converted into the acyl chloride and subsequently treated with amine to yield N-benzyl[carbonyl(11)C]acrylamide, The second method utilizes [C-11]carbon monoxide in a palladium-mediated carbonylative cross-coupling of vinyl halides and amines. A higher radiochemical yield is achieved with the latter method and the amount of amine needed is decreased to 1/20. The C-11-labelled acrylamides were isolated in up to 81 % decay-corrected radiochemical yield. Starting from 10 +/- 0.5GBq of [C-11]carbon monoxide, N-benzyl[carbonyl-C-11]acrylamide was obtained in 4 min with a specific radioactivity of 330 +/- 4 GBq mu mol-(1). Co-labelling with C-11 and C-13 enabled confirmation of the labelled position by C-13 NMR spectroscopy.

    Nyckelord
    Carbonylation, Amides, Carbon monoxide, Isotopic labelling, Carbon-11, 11C, PET
    Nationell ämneskategori
    Kemi
    Forskningsämne
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-98592 (URN)10.1002/ejoc.200600700 (DOI)000243600100007 ()
    Tillgänglig från: 2009-02-27 Skapad: 2009-02-27 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    5. [1-11C]Ethyl iodide and [1-11C]propyl iodide in the synthesis of two potential NK1-receptor ligands and initial PET-imaging
    Öppna denna publikation i ny flik eller fönster >>[1-11C]Ethyl iodide and [1-11C]propyl iodide in the synthesis of two potential NK1-receptor ligands and initial PET-imaging
    Visa övriga...
    (Engelska)Manuskript (Övrigt vetenskapligt)
    Nationell ämneskategori
    Läkemedelskemi
    Identifikatorer
    urn:nbn:se:uu:diva-94933 (URN)
    Tillgänglig från: 2006-10-05 Skapad: 2006-10-05 Senast uppdaterad: 2018-01-13
  • 28.
    Eriksson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Antoni, Gunnar
    Långström, Bengt
    Synthesis of [1-11C]ethyl iodide from carbon monoxide and its application in alkylation reactions2004Ingår i: Journal of Labelled Compounds and Radiopharmaceuticals, ISSN 0362-4803, Vol. 47, nr 11, s. 723-731Artikel i tidskrift (Refereegranskat)
  • 29.
    Eriksson, Ludvig
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Transition Metal Mediated Transformations of Carboranes2003Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes the use of copper and palladium to mediate transformations of carboranes, especially p-carborane.

    1-(1-p-carboranyl)-N-methyl-N-(2-butyl)-3-isoquinolinecarboxamide, a carborane containing analogue of the peripheral benzodiazepine receptor (PBR) ligand PK11195, has been synthesised. A key step in the reaction is the copper (I) mediated coupling of p-carborane with ethyl 1-bromo-isoquinoline-3-carboxylate.

    p-Carborane has been arylated on the 2-B-atom in high yields, using the Suzuki–Miyaura reaction. Thus the reaction between 2-I-p-carborane and various arylboronic acids [1-naphthyl-, phenyl-, 4-MeO-C6H4-, 3-CH3CONH-C6H4-, 4-NC-C6H4-, 3-NO2-C6H4-], gave the corresponding 2-aryl-p-carboranes in DME solution when reacted in the presence of cesium fluoride and the catalytic Pd2(dba)3–dppb system. Under the same conditions, the boron-boron bond forming reaction of two p-carboranylboronic esters (2-[(pinacolato)boron]-p-carborane and 2-[(neopentyl glycolato)boron]-p-carborane) was also shown feasible.

    p-Carborane has been vinylated on the 2-B-atom in high yields by use of the Heck reaction. The coupling between 2-I-p-carborane and various styrenes [4-H-, 4-C6H4-, 4-Cl , 4-Br-, 4-NO2-, 4-CH3O- and 4 CH3 ] resulted in the formation of the correspondingtrans-β-(2-B-p-carboranyl) styrene in DMF solution when reacted in the presence of silver phosphate and the palladacycle Herrmann´s catalyst. The reaction was shown to proceed at higher rate with electron rich than with electron deficient olefins.

    The feasibility of palladium-catalysed isotopic exchange of an iodinated closo-carborane with a radioisotope of iodine has been studied. 2-I-p-carborane was selected as a model compound. It was shown, that such isotopic exchange is possible and provides a high yield (83 ± 4.2 %) during 40 min long reaction. The reaction conditions were optimised, and it was demonstrated that presence of the tetra n-butylammonium hydrogensulphate is important in order to stabilise catalyst and provide reproducibility of labelling. In this work we have modified the methodology and extended the application to a wider range of iodinated carboranes. By the use of Herrmann’s catalyst in toluene at 100 °C this [125I]-iodide labelling could be improved and extended. 2-I-p- 9-I-m-, 9-I-o-, 3-I-o-carborane, 1-phenyl-3-I-o-carborane and 1,2-diphenyl-3-I-o-carborane could be [125I]-iodide labelled in high to excellent yields within 5 minutes.This reported palladium catalyzed radio-iodination of the uncharged closo-carboranes might find use in pharmacokinetic studies of carborane derivatives.

  • 30.
    Fagerlund, Amelie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Sunnerheim, Kerstin
    Dimberg, Lena H.
    Radical-scavenging and antioxidant activity of avenanthramides2009Ingår i: Food Chemistry, ISSN 0308-8146, E-ISSN 1873-7072, Vol. 113, nr 2, s. 550-556Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Avenanthramides are amides of cinnamoyl-anthranilic acids and, among cereals, are exclusively found in oats. This study investigated the structure-antioxidant activities of 15 avenanthramides with different substitution patterns in the two aromatic rings, seven of which were new avenanthramides synthesised and characterised in this study. Radical-scavenging activity was tested as reactivity towards 1,1-diphenyl-2-picrylhydrazyl (DPPH-). The activity increased with the number of radical-stabilising groups ortho to the phenolic hydroxy group. Both aromatic rings were independently important for activity, while conjugation across the amide bond was of minor importance. Antioxidant activity was determined as inhibition of linoleic acid oxidation. In contrast to the radical-scavenging activity, antioxidant activity was observed for most avenanthramides, and also for compounds with only one hydroxy group in either of the aromatic rings. Compared with alpha-tocopherol, the avenanthramides protected linoleic acid from oxidation to a smaller extent initially, but the effect lasted for a longer time.

  • 31.
    Fast, K J
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Bergström, M
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Hedberg, E
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Cheng, A
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Lu, L
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Wu, F
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Bergström, E
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Tolmachev, Vladimir
    Långström, Bengt
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    76-Br-bromodeoxyuridine marker with PET-preclinical validation studies1997Ingår i: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 40, nr 5, s. 391-393Artikel i tidskrift (Refereegranskat)
  • 32.
    Gayet, Arnaud
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Development of New Chiral Bicyclic Ligands: Applications in Catalytic Asymmetric Transfer Hydrogenation, Epoxidations, and Epoxide Rearrangements2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes the synthesis and application of new chiral bicyclic ligands and their application in asymmetric catalysis. The studies involved: [i] The development of novel chiral bicyclic amino sulfur ligands and their use in transfer hydrogenation. [ii] The development of the kinetic resolution of racemic epoxide through the use of chiral lithium amides. [iii] The synthesis and application of chiral bicyclic amine in the organocatalysed epoxidation of alkenes. [iv] Development and application of new chiral diamine ligands in the rearrangement of epoxides into allylic alcohols.

    [i] The preparation of two-series of amino thiol ligands based on the structure of camphor is described, together with their application in the iridium-catalysed asymmetric transfer hydrogenation of acetophenone using isopropanol as the hydrogen source. Excellent activity and good enantioselectivity have been achieved using 2 mol% of chiral ligand in combination with [IrCl(COD)]2.

    [ii] The chiral diamines (1S,3R,4R)-3-(pyrrolidine-1-ylmethyl)-2-aza-bicyclo[2.2.1]heptane and its (2R,5R)-dimethylpyrrolidine derivative were applied to the kinetic resolution of a variety of racemic 5-7 membered cycloalkene oxides with lithium diisopropylamide (LDA) as the bulk base. Using 5 mol% of the chiral diamines, both unreacted epoxides and allylic alcohols could be produced in enantiomeric excess up to 99%.

    [iii] The synthesis of chiral bicyclic amines and their use in the organocatalysed epoxidation of alkene has been described. Using a substoichiometric amount of the chiral amines and aldehydes as ligands precursors, with Oxone® as oxidant, a good activity but moderate enantioselectivity was observed for the epoxidation of trans-stilbene.

    [iv] The preparation of 6-substituted-7-bromo-aza-bicyclo[2.2.1]heptanes via nucleophilic addition of organocopper reagents to 3-bromo-1-azoniatricyclo[2.2.1.0]heptyle bromide has been described. These compounds have been utilised as chiral building blocks in the preparation of novel chiral diamine ligands, which have been successfully applied to the catalysed asymmetric rearrangement of epoxide into the corresponding allylic alcohol.

    Delarbeten
    1. Novel Catalytic Kinetic Resolution Of Racemic Epoxides to Allylic alcohols
    Öppna denna publikation i ny flik eller fönster >>Novel Catalytic Kinetic Resolution Of Racemic Epoxides to Allylic alcohols
    2002 Ingår i: Organic Letters, ISSN 1523-7060, Vol. 4, nr 22, s. 3777-3779Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-92519 (URN)
    Tillgänglig från: 2005-01-10 Skapad: 2005-01-10Bibliografiskt granskad
    2. Development of new camphor based N,S chiral ligands and their application in transfer hydrogenation
    Öppna denna publikation i ny flik eller fönster >>Development of new camphor based N,S chiral ligands and their application in transfer hydrogenation
    2004 Ingår i: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 2, nr 13, s. 1887-1893Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-92520 (URN)
    Tillgänglig från: 2005-01-10 Skapad: 2005-01-10Bibliografiskt granskad
    3. Synthesis of 6-Substituted 7-Bomoazabicyclo[2.2.1]heptanes via Nucleophilic Addition to 3-Bromo-1-azoniatricyclo[2.2.1.0]-heptane Bromide
    Öppna denna publikation i ny flik eller fönster >>Synthesis of 6-Substituted 7-Bomoazabicyclo[2.2.1]heptanes via Nucleophilic Addition to 3-Bromo-1-azoniatricyclo[2.2.1.0]-heptane Bromide
    2005 (Engelska)Ingår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 347, nr 9, s. 1242-1246Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We describe herein an efficient method for the preparation of a functionalised bicyclic framework (6-substituted 7-bromo-aza-bicyclo[2.2.1]heptane) through the selective opening of the aziridium 2 with organocuprates in up to 90% yield. These interesting chiral building blocks were then utilised as novel ligands in the rearrangement of epoxides to afford chiral allylic alcohols.

    Nationell ämneskategori
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-92521 (URN)10.1002/adsc.200404322 (DOI)
    Tillgänglig från: 2005-01-10 Skapad: 2005-01-10 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
  • 33.
    Gayet, Arnaud
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Andersson, Pher G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Synthesis of 6-Substituted 7-Bomoazabicyclo[2.2.1]heptanes via Nucleophilic Addition to 3-Bromo-1-azoniatricyclo[2.2.1.0]-heptane Bromide2005Ingår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 347, nr 9, s. 1242-1246Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe herein an efficient method for the preparation of a functionalised bicyclic framework (6-substituted 7-bromo-aza-bicyclo[2.2.1]heptane) through the selective opening of the aziridium 2 with organocuprates in up to 90% yield. These interesting chiral building blocks were then utilised as novel ligands in the rearrangement of epoxides to afford chiral allylic alcohols.

  • 34.
    Guliashvili, Tamaz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Synthesis and Reactivity Studies of Zwitterionic Silenes and 2-Silenolates2004Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes synthesis and reactivity studies of 2-amino-2-siloxysilenes and 2-silenolates, species that are strongly influenced by reversed Si=C bond polarization, i.e. an Siδ-=Cδ+ polarization as compared to the natural Siδ+=Cδ- polarization. Because of the reversed polarization, the 2-amino-2-siloxysilenes are zwitterions and the 2-silenolates are predominantly described by the resonance structure with the negative charge at Si.

    Transient zwitterionic 2-amino-2-siloxysilenes are formed thermolytically from carbamylpolysilanes (tris(trimethylsilyl)silylamides) and trapped with 1,3-dienes in nearly quantitative yields. These silenes have structure and reactivity characteristics that differ from earlier studied Si=C bonded compounds. They are thermodynamically stable toward dimerization and react with 1,3-dienes to give exclusively [4+2] cycloadducts. Their reactions with 1,3-dienes proceed in accordance with inverse electron demand (IED) Diels-Alder reactions which is explained by the electron-rich nature of these silenes. The 2-amino-2-siloxysilenes are also less reactive toward alcohols than earlier silenes. Hence, alcohols do not react with 2-amino-2-siloxysilenes but with the silene precursor, the carbamylpolysilanes, leading to alkoxysilanes in high yields. The latter reaction represents a novel base-free synthetic protocol for protection of primary and secondary alcohols with the fluoride resistant but photolabile tris(trimethylsilyl)silyl group.

    Another class of formally Si=C bonded compounds, metal 2-silenolates, has been formed in high yields using a novel facile method. Reaction of acyl- and carbamylpolysilanes with potassium tert-butoxide in tetrahydrofurane gives potassium 2-silenolates. The potassium 2-silenolates are stable at room temperature, in contrast to earlier lithium 2-silenolates that degrade rapidly at ambient temperature. The first crystallisable complex of a 2-silenolate was formed and characterized by X-ray crystallography. This 2-silenolate has a pyramidal central Si (ΣSi = 317.8°), and an Si-C single rather than Si=C double bond (r(SiC) = 1.926 Å). The potassium 2-silenolates give exclusively Si alkylated products with alkyl halides and only [4+2] cycloadducts with 1,3-dienes.

    Delarbeten
    1. Evidence for Formation of Silenes Strongly Influenced by Reversed Si=C Bond Polarity
    Öppna denna publikation i ny flik eller fönster >>Evidence for Formation of Silenes Strongly Influenced by Reversed Si=C Bond Polarity
    Visa övriga...
    2002 Ingår i: Organic Letters, ISSN 1523-7060, Vol. 4, nr 11, s. 1915-1918Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-92331 (URN)
    Tillgänglig från: 2004-11-03 Skapad: 2004-11-03Bibliografiskt granskad
    2. Formation of Transient Zwitterionic Silenes and Their Diels-Alder Reactions with 1,3-Dienes: Mechanism and Stereoselectivity
    Öppna denna publikation i ny flik eller fönster >>Formation of Transient Zwitterionic Silenes and Their Diels-Alder Reactions with 1,3-Dienes: Mechanism and Stereoselectivity
    Visa övriga...
    Ingår i: Journal of Americal Chemical Society, ISSN 0002-7863Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-92332 (URN)
    Tillgänglig från: 2004-11-03 Skapad: 2004-11-03Bibliografiskt granskad
    3. The First Unsuccesful attempt to Add Alcohols to a Silene
    Öppna denna publikation i ny flik eller fönster >>The First Unsuccesful attempt to Add Alcohols to a Silene
    Ingår i: Organometallics, ISSN 0276-7333Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-92333 (URN)
    Tillgänglig från: 2004-11-03 Skapad: 2004-11-03Bibliografiskt granskad
    4. The First Isolable 2-Silenolate
    Öppna denna publikation i ny flik eller fönster >>The First Isolable 2-Silenolate
    2003 Ingår i: Angewandte Chemie International Eddition, ISSN 1433-7851, Vol. 42, nr 14, s. 1640-1642Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-92334 (URN)
    Tillgänglig från: 2004-11-03 Skapad: 2004-11-03Bibliografiskt granskad
    5. Potassium 1-N,N-Dialkylamino-2,2-bis(trimethylsilyl)-2-Silenolates: Heavy Enolates with Remarkable Stability
    Öppna denna publikation i ny flik eller fönster >>Potassium 1-N,N-Dialkylamino-2,2-bis(trimethylsilyl)-2-Silenolates: Heavy Enolates with Remarkable Stability
    Visa övriga...
    Manuskript (Övrigt vetenskapligt)
    Identifikatorer
    urn:nbn:se:uu:diva-92335 (URN)
    Tillgänglig från: 2004-11-03 Skapad: 2004-11-03 Senast uppdaterad: 2010-01-13Bibliografiskt granskad
  • 35.
    Guliashvili, Tamaz
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    El-Sayed, Ibrahim
    Fischer, Andreas
    Ottosson, Henrik
    The First Isolable 2-Silenolate2003Ingår i: Angewandte Chemie International Eddition, ISSN 1433-7851, Vol. 42, nr 14, s. 1640-1642Artikel i tidskrift (Refereegranskat)
  • 36.
    Guliashvili, Tamaz
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Martel, Arnaud
    Askelsson, Patrik
    Fischer, Andreas
    Ottosson, Henrik
    Potassium 1-N,N-Dialkylamino-2,2-bis(trimethylsilyl)-2-Silenolates: Heavy Enolates with Remarkable StabilityManuskript (Övrigt vetenskapligt)
  • 37.
    Guliashvili, Tamaz
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Martel, Arnaud
    El-Sayed, Ibrahim
    Fischer, Andreas
    Ottosson, Henrik
    Formation of Transient Zwitterionic Silenes and Their Diels-Alder Reactions with 1,3-Dienes: Mechanism and StereoselectivityIngår i: Journal of Americal Chemical Society, ISSN 0002-7863Artikel i tidskrift (Refereegranskat)
  • 38.
    Guliashvili, Tamaz
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Ottosson, Henrik
    The First Unsuccesful attempt to Add Alcohols to a SileneIngår i: Organometallics, ISSN 0276-7333Artikel i tidskrift (Refereegranskat)
  • 39.
    Holmberg, Pär
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Karlsson, John
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi, Organisk kemi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Enzymatic Kinetic Resolution of 1-(3-furyl)-3-buten-1ol2005Ingår i: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 16, s. 2397-2399Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    The enzymatic kinetic resolution of 1-(3-furyl)-3-buten-1-ol was investigated via the enantioselective hydrolysis of the corresponding acetate. Pseudomonas fluorescens (Fluka) was found to give the highest enantiomeric ratios of the 11 lipases screened. At 51% conversion, the ee value (eep) for the product was found to be 89%, giving an enantiomeric ratio (Ep) of 58, while the ee value (ees) for the substrate was 89%, giving an enantiomeric ratio (Ep) of 38.

  • 40.
    Karimi, Farhad
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    [11C]Carbon Monoxide in Palladium- / Selenium-Promoted Carbonylation Reactions: Synthesis of 11C-Imides, Hydrazides, Amides, Carboxylic Acids, Carboxylic Esters, Carbothioates, Ketones and Carbamoyl Compounds2002Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    [11C]Carbon monoxide in low concentrations has been used in palladium- or seleniummediated carbonylation reactions such as the synthesis of 11C-imides, hydrazides, amides, carboxylic acids, esters, carbothioates, ketones and carbamoyl compounds.

    In these reactions aryl iodides have been used in most cases. However, less reactive aryl triflate, chloride and bromides were activated using tetrabutylammonium iodide.

    The reactivities of nucleophiles may have influence on the radiochemical yield of the 11Clabelled compounds. Carboxyamination of aryl halides using aniline derivatives yielded 10% of the corresponding 11C-amide. However, the radiochemical yields increased significantly when the aniline derivatives were treated with lithium bis(trimethylsilyl)amide. In contrast, this reagent did not improve the radiochemical yields when primary amines such as methylamine and benzylamine were used. In these cases the radiochemical yields were improved by using pempidine.

    11C-Esterification usually gave low yields. However, the radiochemical yields of 11C-esters could be improved by using magnesium bromide and pempidine.

    An excess of ligand may have a significant impact on palladium-promoted carbonylation reaction. The radiochemical yields of 11C-ketones were improved when using excess amounts of tri-o-tolylphosphine.

    (13C)Carbon monoxide may be utilized for the synthesis of 13C-substituated compounds in order to confirm the position of 11C-labelling.

  • 41.
    Lavén, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Wallenborg, Susanne
    Velikyan, Irina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Bergström, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Djodjic, Majda
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Ljung, Jenny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Berglund, Oskar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Edenwall, Niklas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Markides, Karin E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för analytisk kemi.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Radionuclide Imaging of Miniaturized Chemical Analysis Systems2004Ingår i: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 76, nr 23, s. 7102-7108Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose radionuclide imaging as a valuable tool for the study of molecular interactions in miniaturized systems for chemical analysis. Sensitive and quantitative imaging can be performed with compounds labeled with short-lived positron-emitting radionuclides, such as C-11 and Ga-68, within selected parts of the system. Radionuclide imaging is not restricted to transparent materials since the relatively energetic positrons can penetrate high optical density materials. Experimentally, a radiotracer is introduced into the object of study, which is subsequently placed on a phosphor storage plate. After exposure, the plate is scanned with a laser and a digital, quantitative image can be reconstituted. To demonstrate the concept, three types of microstructures suited for integration in chemical analysis systems were imaged with C-11- and Ga-68-labeled tracers. The influence of factors such as geometry of the object and type of radionuclide on resolution and sensitivity was investigated. The resolution ranged from 0.9 to 2.7 mm (fwhm). Measuring low amounts of radioactivity in the three structures, 2-20 Bq could be detected, which corresponded to 2.3-500 amol or 2.4-110 pM tracer. The imaging approach was applied to study analyte concentration and sample dilution effects on the performance of a capillary extraction column integrated in an automated LC-ESI-MS system. The utility of the technique was further illustrated by imaging of microchannels in a zeonor plastic compact disk and in a poly(dimethylsiloxane) material for the study of nonspecific peptide adsorption.

  • 42.
    Löfström, Claes M.G.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Bäckvall, Jan-E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    BF3-induced rearrangement of aziridinocyclopropanes derived from 2-phenylsulfonyl-1,3-dienes: A new approach to the tropane alkaloid skeleton1996Ingår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 37, nr 19, s. 3371-3374s. 3371-3374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Five N-substituted derivatives of 1,2-methylene-3,4-aziridino 2-phenylsulfonyl cycloalkanes (3a-e) were prepared from their corresponding epoxy cyclopropanes via ring opening of the epoxide by sodium azide and subsequent triphenylphosphine induced cyclization. BF3-induced reaction of compounds 3a-e resulted in a rearrangement via a cyclopropyl carbinyl cation intermediate. In the case of tosylaziridine 3c bicyclic product 5, (tropane skeleton), was formed as the major product. With carbamate derivative 3a exclusive rearrangement to fluorocyloheptene 7 took place.

  • 43.
    Meng, QS
    et al.
    Uppsala universitet.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Thibblin, Alf
    Uppsala universitet.
    Concerted and stepwise solvolytic elimination and substitution reactions: Stereochemistry and substituent effects1997Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 119, nr 6, s. 1217-1223s. 1217-1223Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Solvolysis of the R,R and R,S isomers 2a-X and 2b-X, respectively, (X = I, Br, OBs) in 25 vol % acetonitrile in water gives the elimination products 4, 5a, and 5b along with the substitution products 2a-OH, 2b-OH, 2a-NHCOMe, and 2b-NHCOMe. The rates of e

  • 44.
    Nordin, S J M
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Andersson, Pher G
    Ryberg, P
    Evidence for Concerted Proton and Hydride Transfer in the Ru(cymene)(amino alcohol)-Catalyzed Transfer HydrogenationManuskript (Övrigt vetenskapligt)
  • 45.
    Nordin, S J M
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Roth, P
    Tarnai, T
    Alonso, D A
    Brandt, P
    Andersson, Pher G
    Remote Dipole Effects as a Means to Accelerate Ru(Amino alcohol)-Catalyzed Transfer Hydrogenations of Ketones.2001Ingår i: Chem. Eur. J, Vol. 7, s. 1431-Artikel i tidskrift (Refereegranskat)
  • 46.
    Nordin, Sofia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Asymmetric Transfer Hydrogenation of Aromatic Ketones: Catalyst Development and Mechanistic Studies2002Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes the development and evaluation of new chiral Ru(arene)(amino alcohol) catalysts for the transfer hydrogenation of aromatic ketones using isopropanol as the hydrogen source. Two mechanistic studies of the Ru(arene)(amino alcohol) catalyzed transfer hydrogenation of acetophenone were also conducted.

    The Ru(arene)[(1S,3R,4R)-3.(Hydroxymethyl)-2-azabicyclo[2.2.1]heptane] catalyst was optimized for catalytic asymmetric transfer hydrogenation of aromatic ketones. The effect of substituents on the arene ligand on both selectivity and reactivity was investigated. The performance of the catalyst was also optimized by altering the structure of the chiral amino alcohol ligand. These optimizations resulted in a highly active and selective catalyst, Ru(p-cymene)[(R)-1-[(1S,2R,6S,7R,9R)-4,4-Dimethyl-3,5-dioxa-8-aza-tricyclo[5.2.1.00,0]dec-9-yl]-ethanol], for asymmetric transfer hydrogenation of aromatic ketones. This catalyst was capable of reducing acetophenone in 96% ee in 4 minutes at room temperature at a substrate to catalyst ratio of 200. Full conversion was reached even at a substrate to catalyst ratio of 5000 and the high enantioselectivity of 96% ee was maintained. A range of prochiral aromatic ketones with electron withdrawing or electron donating substituents in any position on the aromatic ring were reduced in short reaction times and with high enantioselectivity, up to 99% ee. Bulky aryl alkyl ketones were also reduced with high enantioselectivity.

    A combined quantum chemical and kinetic investigation of the Ru(arene)(amino alcohol) catalyzed transfer hydrogenation of acetophenone was conducted. Three possible mechanisms were studied and the quantum chemical calculations indicated that the mechanism was concerted. In addition, a kinetic isotope study for the Ru(arene)(amino alcohol) catalyzed transfer hydrogenation of acetophenone was conducted. The determination of the kinetic isotope effect of the proton and hydride transfer showed that the proton and the hydride transfer were both rate-limiting and occurred in the same step. This result supports the proposed concerted mechanism.

    Delarbeten
    1. Ru(arene)(amino alcohol)-Catalyzed Transfer Hydrogenation of Ketones: Mechanism and Origin of Enantioselectivity
    Öppna denna publikation i ny flik eller fönster >>Ru(arene)(amino alcohol)-Catalyzed Transfer Hydrogenation of Ketones: Mechanism and Origin of Enantioselectivity
    1999 (Engelska)Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 121, nr 41, s. 9580-9588Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The mechanism of the Ru(arene)(amino alcohol)-catalyzed transfer hydrogenation of ketones using isopropyl alcohol as the hydrogen source has been studied by means of hybrid density functional methods (B3PW91). Three mechanistic alternatives were evaluated, and it was shown that the reaction takes place via a six-membered transition state, where a metal-bound hydride and a proton of a coordinated amine are transferred simultaneously to the ketone. Further calculations provided a general rationale for the rate of the reaction by comparison of steric effects in the ground and transition states of the ruthenium hydride complex. It was found that the TS has a strong preference for planarity, and this in turn is dependent on the conformational behavior of the O,N-linkage of the amino alcohol ligand. Finally, a general model, rationalizing the enantioselectivity of the reaction, was developed. Experimental studies of both rate and enantioselectivity were used in order to support the computational results.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-89926 (URN)10.1021/ja9906610 (DOI)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    2. Evidence for Concerted Proton and Hydride Transfer in the Ru(cymene)(amino alcohol)-Catalyzed Transfer Hydrogenation
    Öppna denna publikation i ny flik eller fönster >>Evidence for Concerted Proton and Hydride Transfer in the Ru(cymene)(amino alcohol)-Catalyzed Transfer Hydrogenation
    Manuskript (Övrigt vetenskapligt)
    Identifikatorer
    urn:nbn:se:uu:diva-89927 (URN)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17 Senast uppdaterad: 2010-01-13Bibliografiskt granskad
    3. New Expidient Route to Both Enantiomers of Nonproteinogenic Amino Acid Derivatives from the Unsaturated 2-Aza-bicyclo Moiety. D. A
    Öppna denna publikation i ny flik eller fönster >>New Expidient Route to Both Enantiomers of Nonproteinogenic Amino Acid Derivatives from the Unsaturated 2-Aza-bicyclo Moiety. D. A
    Visa övriga...
    1999 Ingår i: J. Org. Chem., Vol. 64, s. 2276-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-89928 (URN)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17Bibliografiskt granskad
    4. 2-Azanorbornyl alcohols: Very efficient Ligands for Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of Aromatic Ketones. D. A
    Öppna denna publikation i ny flik eller fönster >>2-Azanorbornyl alcohols: Very efficient Ligands for Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of Aromatic Ketones. D. A
    Visa övriga...
    1999 Ingår i: J. Org. Chem., Vol. 65, s. 3116-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-89929 (URN)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17Bibliografiskt granskad
    5. Highly Diastereoselective Reaction of 2-Azanorbornyl Enolates with Electrophiles. D. A
    Öppna denna publikation i ny flik eller fönster >>Highly Diastereoselective Reaction of 2-Azanorbornyl Enolates with Electrophiles. D. A
    1999 Ingår i: Org. Lett., Vol. 1, s. 1595-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-89930 (URN)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17Bibliografiskt granskad
    6. Remote Dipole Effects as a Means to Accelerate Ru(Amino alcohol)-Catalyzed Transfer Hydrogenations of Ketones.
    Öppna denna publikation i ny flik eller fönster >>Remote Dipole Effects as a Means to Accelerate Ru(Amino alcohol)-Catalyzed Transfer Hydrogenations of Ketones.
    Visa övriga...
    2001 Ingår i: Chem. Eur. J, Vol. 7, s. 1431-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-89931 (URN)
    Tillgänglig från: 2002-05-17 Skapad: 2002-05-17Bibliografiskt granskad
  • 47.
    Norgren, Anna S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Conformational Stability!?: Synthesis and Conformational Studies of Unnatural Backbone Modified Peptides2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The beauty of the wide functionality of proteins and peptides in Nature is determined by their ability to adopt three-dimensional structures. This thesis describes artificial molecules developed to mimic secondary structures similar to those found crucial for biological activities.

    In the first part of this thesis, we focused on post-translational modifications of a class of unnatural oligomers known as β-peptides. Through the design and synthesis of a glycosylated β3-peptide, the first such hybrid conjugate was reported. In this first report, a rather unstable 314-helical structure was found. Subsequently, a collection of six new glycosylated β3-peptides was synthesized with the aim to optimize the helical stability in water.

    The ability of natural proteins, i.e. lectins, to recognize the carbohydrate residue on these unnatural peptide backbones was investigated through a biomolecular recognition study.

    The second part of this thesis concerns the design of conformationally homogeneous scaffolds, which could be of importance for biomedical applications. In paper V, four- and five-membered cyclic all-β3-peptides were investigated for this purpose. In a subsequent paper, a completely different strategy was employed; herein, the ability of a single β2-amino acid to restrict the conformational freedom of a cyclic α-peptide was studied.

    In the third part of this thesis, we synthesized and investigated the folding propensities of novel backbone modified oligomers, i.e. β-peptoids (N-substituted β-Ala) with α-chiral side chains.

    The collective results of these studies have established the procedures required for synthesis of glycosylated β-peptides and deepened our understanding of the factors governing folding among such oligomers. Moreover, it was established that β-amino acids can be a useful tool to increase conformational stability of cyclic peptides.

    Delarbeten
    1. Glycosylated Foldamers: Synthesis of Carbohydrate-modified β3hSer and Incorporation into β-Peptides
    Öppna denna publikation i ny flik eller fönster >>Glycosylated Foldamers: Synthesis of Carbohydrate-modified β3hSer and Incorporation into β-Peptides
    2007 (Engelska)Ingår i: Journal of Peptide Science, ISSN 1075-2617, E-ISSN 1099-1387, Vol. 13, nr 11, s. 717-727Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Fmoc-protected β3hserine (β3hSer) was prepared and O-linked to suitably protected N-acetylgalactosamine (GalNAc) and N-acetylglucosamine (GlcNAc) derivatives. Glycosylation of β3hSer was made by two independent routes: either by direct glycosyl linkage to the β3hSer, or linkage to natural L-Ser and then utilizing the carbohydrate moiety as a protecting group in an Arndt–Eistert homologation. Both procedures gave the novel glycosylated β3-amino acids Fmoc-β3hSer(α-D-GalNAc(Ac)3)-OH (1a), its β-anomer (1b), and Fmoc-β3hSer(β-D-GlcNAc(Ac)3)-OH (2), which were utilized in the solid-phase peptide synthesis of four glycosylated dipeptides (3a–d) and two heptapeptides (4a–b). The preparation of β-amino acids bearing common post-translational modifiers represents an important step towards functionalized foldamers with broad applications in biomedical research.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-95278 (URN)10.1002/psc.832 (DOI)000252622900004 ()17890640 (PubMedID)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    2. Functionalized foldamers: synthesis and characterization of a glycosylated β-peptide 314-helix conveying the Tn-antigen
    Öppna denna publikation i ny flik eller fönster >>Functionalized foldamers: synthesis and characterization of a glycosylated β-peptide 314-helix conveying the Tn-antigen
    2005 Ingår i: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 3, nr 8, s. 1359-1361Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-95279 (URN)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22Bibliografiskt granskad
    3. Glycosylated β3-Peptides: Relationship Between Peptide Sequence and 314-Helical Stability in Water
    Öppna denna publikation i ny flik eller fönster >>Glycosylated β3-Peptides: Relationship Between Peptide Sequence and 314-Helical Stability in Water
    Artikel i tidskrift (Refereegranskat) Submitted
    Identifikatorer
    urn:nbn:se:uu:diva-95280 (URN)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22Bibliografiskt granskad
    4. Biomolecular Recognition of Glycosylated β3-Peptides by GalNAc Specific Lectins
    Öppna denna publikation i ny flik eller fönster >>Biomolecular Recognition of Glycosylated β3-Peptides by GalNAc Specific Lectins
    2007 (Engelska)Ingår i: Journal of Molecular Recognition, ISSN 0952-3499, E-ISSN 1099-1352, Vol. 20, nr 2, s. 132-138Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The molecular recognition of a novel kind of hybrid conjugates, composed of artificial biomimetic β-peptide oligomers with an O-linked natural N-acetyl-galactosamine (the Tn-antigen) residue, by four different GalNAc specific lectins was investigated using surface plasmon biosensor technology. The influence of the peptide and the glycosyl moiety on the recognition was studied using two glycosylated β3-heptapeptides, a glycosylated α-heptapeptide, two β-amino acid containing dipeptides, and monomeric αGalNAc-O-Thr. Although all four lectins displayed a decreased affinity for the carbohydrate residue when attached to a peptide, as compared to the monomeric Tn-antigen, the peptide part was found to have distinct effects on the binding kinetics - indicating that varying degrees of protein-peptide interactions occurred in the recognition process. Likewise, the lectins did not discriminate between β3-peptides and the α-peptide, but the β- linkage of the galactose had a detrimental effect for at least two of the lectins.

    Nyckelord
    b-peptides, glycopeptides, lectins, molecular recognition, surface plasmon resonance
    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-95281 (URN)10.1002/jmr.821 (DOI)000246169000008 ()17410519 (PubMedID)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    5. Cyclic β-tetra- and pentapeptides: Synthesis through on-resin cyclization and conformational studies by X-ray, NMR and CD spectroscopy and theoretical calculations
    Öppna denna publikation i ny flik eller fönster >>Cyclic β-tetra- and pentapeptides: Synthesis through on-resin cyclization and conformational studies by X-ray, NMR and CD spectroscopy and theoretical calculations
    Visa övriga...
    2005 Ingår i: Chemistry--A European Journal, ISSN 0947-6539, Vol. 11, nr 21, s. 6145-6158Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-95282 (URN)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22Bibliografiskt granskad
    6. β2-Amino Acids in the Design of Conformationally Homogeneous cyclo-Peptide Scaffolds
    Öppna denna publikation i ny flik eller fönster >>β2-Amino Acids in the Design of Conformationally Homogeneous cyclo-Peptide Scaffolds
    Visa övriga...
    2006 (Engelska)Ingår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 71, nr 18, s. 6814-6821Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Herein, we report studies on the influence of chiral, beta(2)-amino acids in the design of conformationally homogeneous cyclic tetrapeptide scaffolds. The cyclic alpha-tetrapeptide cyclo(-Phe-D-Pro-Lys-Phe-) (1) and its four mixed analogues, having one of the alpha-Phe replaced by either an (S)-or an (R)-beta(2)hPhe residue (i.e., cyclo(-(R)-beta(2)hPhe-D-Pro-Lys-Phe) (2a), cyclo(-(S)-beta(2)hPhe-D-Pro-Lys-Phe-) (2b), cyclo(-Phe-D-Pro-Lys-(R)-beta(2)hPhe-) (3a), and cyclo(- Phe- D- Pro- Lys-( R)-, 2hPhe-) ( 3b)), were all synthesized through solidphase procedures followed by solution- phase cyclization. Initially, all five cyclo- peptides were analyzed by H-1 NMR spectroscopic studies in different solvents and at variable temperatures. Subsequently, a detailed 2D NMR spectroscopic analysis of three of the mixed peptides in water was performed, and the information thus extracted was used as restraints in a computational study on the peptides' conformational preference. An X- ray crystallographic study on the side chain- protected (Boc) 2a revealed the solid- state structure of this peptide. The results presented herein, together with previous literature data on beta(3)-amino acid residues, conclusively demonstrate the potential of beta-amino acids in the design of conformationally homogeneous cyclic peptides that are homologous to peptides with known applications in biomedicinal chemistry and as molecular receptors.

    Nationell ämneskategori
    Kemi
    Identifikatorer
    urn:nbn:se:uu:diva-95283 (URN)10.1021/jo060854n (DOI)000240020100013 ()16930031 (PubMedID)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    7. Synthesis and circular dichroism spectroscopic investigations of oligomeric β-peptoids with α-chiral side chains
    Öppna denna publikation i ny flik eller fönster >>Synthesis and circular dichroism spectroscopic investigations of oligomeric β-peptoids with α-chiral side chains
    2006 (Engelska)Ingår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 8, nr 20, s. 4533-4536Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Biomimetic oligomers are of large interest both as targets for combinatorial and parallel synthetic efforts and as foldamers. For example, shorter peptoid derivatives of beta-peptides, i.e., oligo-N-substituted beta-Ala, have been described as potential lead structures. Herein, we describe a solid-phase synthetic route to beta-peptoids with alpha-chiral aromatic N-substituents up to 11 residues long. Furthermore, the folding propensities of these oligomers were investigated by circular dichroism (CD) spectroscopy.

    Nationell ämneskategori
    Biokemi och molekylärbiologi
    Identifikatorer
    urn:nbn:se:uu:diva-95284 (URN)10.1021/ol061717f (DOI)000240654700038 ()16986943 (PubMedID)
    Tillgänglig från: 2006-12-22 Skapad: 2006-12-22 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
  • 48.
    Norgren, Anna S.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Arvidsson, Per I.
    Functionalized foldamers: synthesis and characterization of a glycosylated β-peptide 314-helix conveying the Tn-antigen2005Ingår i: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 3, nr 8, s. 1359-1361Artikel i tidskrift (Refereegranskat)
  • 49.
    Norgren, Anna S.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Arvidsson, Per I.
    Glycosylated β3-Peptides: Relationship Between Peptide Sequence and 314-Helical Stability in WaterArtikel i tidskrift (Refereegranskat)
  • 50.
    Rahman, Obaidur
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Llopi, Jordi
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen, Avdelningen för organisk kemi.
    Organic Bases as Additives to Improve the Radiochemical Yields of [11C]Ketones Prepared by the Suzuki Coupling Reaction2004Ingår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2004, nr 12, s. 2674-2678Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Suzuki cross-coupling reaction was employed in the syntheses of eight new [11C-carbonyl]ketones. The reactions between the corresponding boronic acids and the corresponding triflates were performed in the presence of [11C]carbon monoxide and a palladium(0) complex as the catalyst. Lithium bromide was added to facilitate the reactions, and different bases were tested to improve the radiochemical yields. All the ketones were synthesised, with the achievement of isolated radiochemical yields (decay-corrected) of between 14 and 74%. Important improvements in the radiochemical yield were achieved by use of tetrabutylammonium fluoride in the synthesis of ketones incorporating alkyl groups, while potassium tert-butoxide was the best base among those tested for improving the radiochemical yields in the syntheses of biaryl ketones. The optimal amount of base was determined in all cases. Only for compounds 3e and 3h were better radiochemical yields obtained when no base was used. No radiochemical impurities were detected after isolation of the compounds. The specific radioactivity for compound 3a was determined, and a value of 200 GBq/μmol was obtained. Compound 3b was labelled simultaneously with [11C] and (13C)carbon monoxide and the position of the labelled atom was determined and confirmed by 13C NMR spectrometry. Tetrabutylammonium fluoride and potassium tert-butoxide are reported as useful bases for Suzuki carbonylation with [11C]/(13C)carbon monoxide.

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