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  • 1. Aeluri, Madhu
    et al.
    Gaddam, Jagan
    Trinath, Devarakonda V. K. S.
    Chandrasekar, Gayathri
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Kitambi, Satish Srinivas
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies. Karolinska institutet.
    Arya, Prabhat
    An Intramolecular Heck Approach To Obtain 17-Membered Macrocyclic Diversity and the Identification of an Antiangiogenesis Agent from a Zebrafish Assay2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 19, p. 3955-3958Article in journal (Refereed)
    Abstract [en]

    We report a practical and modular approach to obtain two different types of 17-membered ring macrocyclic compounds through an intramolecular Heck reaction. These macrocyclic compounds are functionalized, that is, they contain two contiguous stereogenic hydroxy functional groups and an amino acid moiety in the macrocyclic ring skeleton. The macrocycles were then screened against a zebrafish assay to determine the antiangiogenesis activity of these small molecules. Macrocyclic compound 2.2a was identified as a potent inhibitor at 2.5 M, whereas its acyclic precursor and the other related macrocyclic compounds did not show any effect.

  • 2.
    Andersson, Claes-Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Grennberg, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Reproducibility and efficiency of carbon nanotube end-group generation and functionalization2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 26, p. 4421-4428Article in journal (Refereed)
    Abstract [en]

    In a systematic fashion, several methods for esterification and  amidation of single-walled carbon nanotubes have been evaluated with   focus on efficiency and reproducibility in forming covalently   functionalized products soluble in organic media. The outcome of   transformations was determined using IR, Raman and NMR spectroscopy and   by thermogravimetric analysis (TGA). Amidation proceeding via a   SWNT-(COCl)(n) intermediate yielded the expected covalent product,  whereas carboxylate salt formation dominated with other attempted   methods. Esterification was achieved via the acyl chloride method and   via alkylation of SWNT-(COO-)(n), the latter being the more efficient   method. A non-covalent solubilizing interaction was obtained for RNH2   but not for ROH (R = octadecyl), proving that the most important   non-covalent interaction between oxidatively cleaned SWNTs and   octadecylamine is a salt formation. The outcome of the secondary   functionalization of carboxyl units is highly reproducible for   experiments carried out on the same batch of SWNT-(COOH)(n). Normalization of the outcome of the secondary functionalization to the   composition of the different batches of starting materials reveals an overall high reproducibility of the secondary function alizations. The   differences in outcome related to different commercial SWNT batches   from the same synthetic procedure is negligible compared to that   resulting from differences in overall carboxyl content after the   primary HNO3 oxidative cleaning step. Hence, the composition of   purified SWNT starting materials always needs to be assessed, in particular before drawing any conclusions concerning differences in   outcome from reaction systems involving different sources of SWNT  material.

  • 3.
    Andersson, Samir
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zou, Dapeng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zhang, Rong
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Sun, Shiguo
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Åkermark, Björn
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Selective Positioning of CB 8 on Two Linked Viologens and Electrochemically Driven Movement of the Host Molecule2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 8, p. 1163-1172Article in journal (Refereed)
    Abstract [en]

    The binding interactions between cucurbit[8]uril (CB[8]) and a dicationic guest N,N-dimethyl-3,3'-dimethyl-4,4'-bipyridinium (DMV2+) have been investigated by various experimental techniques including NMR, ESI-MS, and UV/Vis and fluorescence spectroscopy. In a three-component system consisting of CB[81, N,N-dimethyl-4,4'-bipyridinium (MV2+) and DMV2+, CB[8] was found to exhibit a higher binding affinity to DMV2+ than to MV2+, When DMV2+ was connected to MV2+ by an alkyl chain, the first equiv. of CB[8] could be selectively positioned on the DMV2+ moiety, and then a second equiv. of CB[8] was positioned on the MV2+ moiety. Spectroelectrochemical studies showed that upon the reduction of this system at -0.6 V vs. AgCl, the CB[8] could move from the DMV2+ moiety to the MV+center dot radical, which formed a dimer inside the CB[8] cavity. Molecular oxygen quenched the dimer, and the CB[8] moved back to the DMV2+ moiety, indicating it molecular movement driven by electrochemistry. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

  • 4. Andersson, Samir
    et al.
    Zou, Dapeng
    Zhang, Rong
    Sun, Shiguo
    Åkermark, Björn
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Licheng
    Selective positioning of CB[8] on two linked viologens and electrochemically driven movement of the host molecule2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 8, p. 1163-1172Article in journal (Refereed)
  • 5. Angelin, Marcus
    et al.
    Hermansson, Magnus
    Dong, Hai
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Direct, mild, and selective synthesis of unprotected dialdo-glycosides2006In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 19, p. 4323-4326Article in journal (Refereed)
    Abstract [en]

    A direct and highly convenient organocatalytic method for the preparation of 1,5-dialdo-pyranosides and 1,4-dialdo-furanosides is presented. The method relies on the chemoselective properties of TEMPO in combination with trichloroisocyanuric acid under very mild, basic conditions. Unprotected glycosides are prepared in a single step in high yields and are efficiently purified with the use of solid-phase imine capture. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).

  • 6.
    Angelin, Marcus
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongvilai, Pornrapee
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fischer, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Crystallization Driven Asymmetric Synthesis of Pyridine β-Nitroalcoholsvia Discovery-Oriented Self-Resolution of a Dynamic System2010In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 33, p. 6315-6318Article in journal (Refereed)
    Abstract [en]

    The study of dynamic nitroaldol systems aided the discovery of a diastereoselective crystallization process through amplification of 2-nitro-1-(pyridine-4-yl)propan-1-ol. The phenomenon was further developed into an effective procedure for asymmetic synthesis of pyridine-nitroalcohols and several substrates were screened to this end. These results demonstrate how work with larger dynamic systems facilitates and increases the likelihood of serendipitous discoveries.

  • 7.
    Ankner, Tobias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Physical Organic Chemistry.
    Norberg, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC.
    Kihlberg, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Physical Organic Chemistry.
    Mild Oxidative Cleavage of 9-BBN-Protected Amino Acid Derivatives2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 17, p. 3767-3770Article in journal (Refereed)
    Abstract [en]

    Protection of the amino acid moiety using 9-BBN is an effective method to enable side chain manipulations in synthesis of complex amino acids. We investigated the standard, mild method for deprotection of the 9-BBN group in methanolic chloroform, and found that it relies on a slow oxidation mediated by molecular oxygen. Building on this insight, we have developed a method that allows for a fast and selective deprotection using simple peroxy acid reagents. After Fmoc protection, products were isolated in >90% yield for a series of amino acid derivatives, including a galactosylated derivative of hydroxylysine.

  • 8.
    Appukkuttan, Prasad
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Van der Eycken, Erik
    Recent developments in microwave-assisted, transition-metal-catalysed C-C and C-N bond-forming reactions2008In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 7, p. 1133-1155Article, review/survey (Refereed)
    Abstract [en]

    A selective over-view of the recent developments of microwave-assisted, transition-metal-catalysed C-C and C-N bond-forming reactions is presented. Microwave-assisted chemistry is a comparatively novel technique in the present-day synthetic world and has recently grown in an exponential manner, stretching from academia to a widely practiced technique in industry. Transition-metal-catalysed C-C and C-N bond-forming reactions represent one of the most interesting and well-investigated type of microwave-assisted reactions, evident from the plethora of available literature and patents in this area. Given the large number of articles published on the subject, we have made a very concise selection from the recent literature, covering manuscripts dealing with the subject from the period of the end 2004 until the first part of 2007.

  • 9.
    Arkhypchuk, Anna I.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Orthaber, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Kovacs, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Borbas, K. Eszter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Isolation and Characterization of a Monoprotonated Hydroporphyrin2018In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 48, p. 7051-7056Article in journal (Refereed)
    Abstract [en]

    A simple protocol for the controlled preparation of mono- and diprotonated hydroporphyrins (chlorins) is presented. The chlorins carried 10-aryl groups with electron-neutral (phenyl), electron-donating (p-OMe-C6H4) or electron-withdrawing (pentafluorophenyl) substituents. The protonation reactions were readily followed by UV/Vis absorption spectroscopy, enabling the determination of the first (4.8-5.3) and second pK(a)'s (1.7-0.5). Both mono- and diprotonated species were fully characterized by H-1 NMR spectroscopy, which, in combination with theoretical studies, showed that these macrocycles were significantly distorted in solution. A 10-phenyl-substituted monoprotonated chlorin was characterized by X-ray crystallography. This is the first structurally characterized hydroporphyrin monocation, and the first crystal structure of a sterically unencumbered singly protonated tetrapyrrole. The photostabilities of the mono- and diprotonated 10-phenylchlorins were measured upon irradiation into their Soret bands; protonation yielded increased photostabilities.

  • 10.
    Belfrage, Anna Karin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Gising, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Svensson, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Åkerblom, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Sköld, Christian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Sandström, Anja
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Efficient and Selective Palladium-Catalysed C-3 Urea Couplings to 3,5-Dichloro-2(1H)-pyrazinones2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 5, p. 978-986Article in journal (Refereed)
    Abstract [en]

    The development of a robust palladium-catalysed urea N-arylation protocol to install various ureas at the 3-position of the 2(1H)-pyrazinone scaffold is described. The method involves Pd(OAc)2 in combination with bidentate ligands, xantphos [4,5-bis(diphenylphosphino)-9,9-dimethylxanthene] in particular, and resulted in good to excellent coupling yields of aliphatic, aromatic, and sterically hindered ureas. Furthermore, the C-3 chlorine was shown to be selectively displaced in the presence of aryl halide ureas, and this finding was supported by density functional theory (DFT) calculations. This allows further diversification of the scaffold for the production of compound libraries. Overall, the protocol facilitates further exploitation of pyrazinones as beta-sheet-inducing scaffolds in the development of sophisticated peptidomimetics/protease inhibitors. This is exemplified here by the synthesis of a new pyrazinone-based hepatitis C virus (HCV) NS3 protease inhibitor.

  • 11.
    Belfrage, Anna Karin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Wakchaure, Prasad
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Larhed, Mats
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Sandström, Anja
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Palladium-Catalyzed Carbonylation of Aryl Iodides with Sulfinamides2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 32, p. 7069-7074Article in journal (Refereed)
    Abstract [en]

    A facile palladium(0)-catalyzed carbonylative protocol for the generation of new acyl-sulfinamides in moderate to good yields is described. Aliphatic and aromatic sulfinamides were exploited as hitherto unexplored nucleophiles in carbonylation chemistry, with use of CO gas generated ex situ from Mo(CO)6 in a sealed two-chamber system. Both electron-poor and electron-rich (hetero)aryl iodides were employed as electrophiles. The two-chamber system and the use of an inorganic base were essential for efficacious synthesis of acyl-sulfinamide products. Finally, it was demonstrated that a one-pot (or single-vial) synthesis of acyl-sulfinamides was feasible under CO at balloon pressure in the presence of Cs2CO3 as base.

  • 12.
    Bergström, Maria
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Ganji, Suresh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Naidu Veluru, Ramesh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    N-Iodosuccinimide (NIS) in Direct Aromatic Iodination2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 22, p. 3234-3239Article in journal (Refereed)
    Abstract [en]

    N-Iodosuccinimide (NIS) in pure trifluoroacetic acid (TFA) offers a time-efficient and general method for the iodination of a wide range of mono-and disubstituted benzenes at room temperature, as demonstrated in this paper. The starting materials were generally converted into mono-iodinated products in less than 16 hours at room temperature, without byproducts. A few deactivated substrates needed addition of sulfuric acid to increase the reaction rate. Another exception was methoxybenzenes that preferentially were iodinated by NIS in acetonitrile with only catalytic amounts of TFA.

  • 13.
    Bogár, Krisztián
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Krumlinde, Patrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bacsik, Zoltán
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Hedin, Niklas
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Bäckvall, Jan E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Heterogenized Wilkinson's Catalyst for Transfer Hydrogenation of Carbonyl Compounds2011In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 23, p. 4409-4414Article in journal (Refereed)
    Abstract [en]

    Wilkinson’s catalyst [RhCl(PPh3)3] was heterogenized on common silica by the use of a grafting/anchoring technique. The immobilized catalyst showed high activity and selectivity in transfer hydrogenation reactions of a range of carbonyl compounds in 2-propanol. Reactions carried out in 2-propanol at reflux afforded the corresponding alcohols in high yields in short reaction times. The heterogeneous feature ofthe catalyst allows for easy recovery and efficient reuse in the same reaction up to 5 times without any detectible loss of catalytic activity.

  • 14. Chakka, Sai Kumar
    et al.
    Andersson, Pher G
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Maguire, Glenn E. M.
    Kruger, Hendrik G.
    Govender, Thavendran
    Synthesis and Screening of C-1-Substituted Tetrahydroisoquinoline Derivatives for Asymmetric Transfer Hydrogenation Reactions2010In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 5, p. 972-980Article in journal (Refereed)
    Abstract [en]

    Tetrahydroisoquinoline (TIQ) derivatives exhibit good biological activity. However, utilization of TIQ compounds in asymmetric catalysis is limited. This paper presents a series of TIQ derivatives in asymmetric transfer hydrogenation (ATH) reactions. Chiral TIQ amino alcohol ligands were synthesized and screened for the ATH reaction of aromatic ketones. The effect of a cis- and trans-phenyl substitution at the C-1 position on the ligand backbone was investigated both experimentally and computationally. The results showed that the trans orientation on the TIQ scaffold yields higher turnover rates with a selectivity of 94% ee obtained at room temperature with an Ru complex. The cis isomer results in a high turnover rate with no selectivity. The trans isomer gave 99% ee at lower temperatures. Furthermore, it was observed that substitution at the C-3-alpha position results in a drop of the enantioselectivity and the reactivity of the catalyst.

  • 15. Chamakuri, Srinivas
    et al.
    Guduru, Shiva Krishna Reddy
    Pamu, Sreedhar
    Chandrasekar, Gayathri
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Kitambi, Satish Srinivas
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies. Karolinska institutet.
    Arya, Prabhat
    A Modular Approach to Build Macrocyclic Diversity in Aminoindoline Scaffolds Identifies Antiangiogenesis Agents from a Zebrafish Assay2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 19, p. 3959-3964Article in journal (Refereed)
    Abstract [en]

    A modular approach to explore the macrocyclic chemical space around an aminoindoline scaffold is developed. This is achieved by incorporating an amino acid moiety and subsequent stitching technology. Through screening of a zebrafish assay, several antiangiogenesis agents are identified.

  • 16. Chassagne, Pierre
    et al.
    Fontana, Carolina
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Guerreiro, Catherine
    Gauthier, Charles
    Phalipon, Armelle
    Widmalm, Göran
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Mulard, Laurence A.
    Structural Studies of the O-Acetyl-Containing O-Antigen from a Shigella flexneri Serotype 6 Strain and Synthesis of Oligosaccharide Fragments Thereof2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 19, p. 4085-4106Article in journal (Refereed)
    Abstract [en]

    Extensive analysis by NMR spectroscopy of the delipidated lipopolysaccharide of Shigella flexneri serotype 6 strain MDC 2924-71 confirmed the most recently reported structure of the O-antigen repeating unit as {4)--D-GalpA-(13)--D-GalpNAc-(12)--L-Rhap3Ac/4Ac-(12)--L-Rhap-(1}, and revealed the non-stoichiometric acetylation at O-3C/4C. Input from the CASPER program helped to ascertain the fine distribution of the three possible patterns of O-acetylation. The non-O-acetylated repeating unit (ABCD) corresponded to about 2/3 of the population, while 1/4 was acetylated at O-3C (3AcCDAB), and 1/10 at O-4C (4AcCDAB). Di- to tetrasaccharides with a GalpA residue (A) at their reducing end were synthesized as their propyl glycosides following a multistep linear strategy relying on late-stage acetylation at O-3C. Thus, the 3C-O-acetylated and non-O-acetylated targets were synthesized from common protected intermediates. Rhamnosylation was most efficiently achieved by using imidate donors, including at O-4 of a benzyl galacturonate acceptor. In contrast, a thiophenyl 2-deoxy-2-trichloroacetamido-D-galactopyranoside precursor was preferred for chain elongation involving residue B. Final Pd/C-mediated deprotection ensured O-acetyl stability. All of the target molecules represent parts of the O-antigen of S. flexneri 6, a prevalent serotype. Non-O-acetylated oligosaccharides are also fragments of the Escherichia coli O147 O-antigen.

  • 17. Chen, Long
    et al.
    Li, Xin
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Ying, Weijiang
    Zhang, Xiaoyu
    Guo, Fuling
    Li, Jing
    Hua, Jianli
    5,6-Bis(octyloxy)benzo[c][1,2,5]thiadiazole-Bridged Dyes for Dye-Sensitized Solar Cells with High Open-Circuit Voltage Performance2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 9, p. 1770-1780Article in journal (Refereed)
    Abstract [en]

    Three new metal-free dyes with a 5,6-bis(octyloxy) benzo[c][1,2,5] thiadiazole core (DOBT-I-III) have been designed and synthesized for use as DSSCs. Their absorption properties and electrochemical and photovoltaic performances have been investigated systematically. The DSSCs based on DOBT-I-III show high open-circuit voltages (V-oc) of 829, 818, and 784 mV, respectively. Of the three dyes, DOBT-III, which contains a thiophene-bridging linker, exhibits the best photovoltaic performance: a short-circuit photocurrent density (J(sc)) of 12.74 mA cm(-2) and a fill factor (FF) of 0.73, which corresponds to an overall conversion efficiency of 7.29% under standard global AM 1.5 solar conditions.

  • 18.
    Chinthakindi, Praveen K.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Arvidsson, Per I.
    Univ KwaZulu Natal, Catalysis & Peptide Res Unit, Durban, South Africa;Karolinska Inst, Sci Life Lab, Drug Discovery & Dev Platform, Stockholm, Sweden;Karolinska Inst, Div Translat Med & Chem Biol, Dept Med Biochem & Biophys, Stockholm, Sweden.
    Sulfonyl Fluorides (SFs): More Than Click Reagents?2018In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 27-28, p. 3648-3666Article, review/survey (Refereed)
    Abstract [en]

    Sulfonyl fluoride (SF) containing substances are currently attracting enormous attention among practitioners of both chemical biology and synthetic organic chemistry. The groups of Jones and Liskamp have demonstrated the potential of sulfonyl fluorides as selective covalent inhibitors in studies related to drug discovery and chemical biology, respectively, in the last few years. The Sharpless group has extended the repertoire of click-reactions to those involving sulfonyl fluorides, that is, sulfur-fluoride exchange (SuFEx), a development that quickly triggered the interest in this functional group in the community of synthetic organic chemists. In this microreview, we aim to give an account of the synthetic chemistry surrounding sulfonyl fluoride containing substances from a historical perspective to present day developments.

  • 19.
    Chinthakindi, Praveen K.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Benediktsdottir, Andrea
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Ibrahim, Ayah
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Wared, Atta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Aurell, Carl-Johan
    AstraZeneca, Large Scale Chem, Early Chem Dev, Pharmaceut Sci,IMED Biotech Unit, S-43183 Gothenburg, Sweden.
    Pettersen, Anna
    AstraZeneca, Early Prod Dev, Pharmaceut Sci, IMED Biotech Unit, S-43183 Gothenburg, Sweden.
    Zamaratski, Edouard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Arvidsson, Per I.
    Karolinska Inst, Sci Life Lab, Drug Discovery & Dev Platform, S-17177 Stockholm, Sweden;Karolinska Inst, Dept Med Biochem & Biophys, Div Translat Med & Chem Biol, S-17177 Stockholm, Sweden;Univ KwaZulu Natal, Catalysis & Peptide Res Unit, ZA-4000 Durban, South Africa.
    Chen, Yantao
    AstraZeneca, Med Chem, Cardiovasc Renal & Metab, IMED Biotech Unit, S-43183 Gothenburg, Sweden.
    Sandström, Anja
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Drug Design and Discovery.
    Synthesis of Sulfonimidamide-Based Amino Acid Building Blocks with Orthogonal Protecting Groups2019In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 5, p. 1045-1057Article in journal (Refereed)
    Abstract [en]

    Herein, we report the synthesis of novel sulfonimidamides (SIAs) based on amino acid building blocks using a one-pot method from tert-butyldiphenylsilyl-protected (TBDPS) sulfonamides, as well as exploration of orthogonal deprotection strategies. Among the several protecting groups investigated, TBDPS showed higher conversion, allowed UV detection and simple diastereomeric separation; in particular in combination with amino acid tert-butyl esters. Moreover, we applied the present method to synthesize cyclic five-membered acyl sulfonimidamides in two steps. The described synthesis of SIA-based amino acid building blocks in combination with the orthogonal protection groups provide access to unnatural amino acid building blocks useful for further incorporation into larger molecules, such as peptide-based transition-state analogues and peptidomimetics. The chirality of the SIA group, as well as its additional point of diversity provided by the extra NH group, creates opportunities for the development of unique compound libraries that explore new chemical space, which is of considerable importance for the pharmaceutical and agrochemical industry.

  • 20.
    Chorell, Erik
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Chorell, Elin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Efficient Synthesis of 2-Substituted Phthalimides from Phthalic Acids in One Step2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2013, no 33, p. 7512-7516Article in journal (Refereed)
    Abstract [en]

    Efficient procedures for synthesizing 2-substituted phthalimide (isoindole-1,3-dione) analogues starting from phthalic acids have been developed by using experimental design. The phthalimide central fragment frequently appears in biologically active compounds, materials, catalysts, and fluorescent probes, and therefore the development of general, fast, and convenient synthetic methods to this scaffold under neutral, acidic, and basic conditions would be attractive. After an initial screening, the use of acetonitrile, acetic acid, or pyridine in combination with microwave heating proved most promising. Experimental design was applied to these conditions to optimize the time, temperature, and concentration. This strategy has successfully generated synthetic methods that have been used to synthesize a series of phthalimides from phthalic acids and various amines or anilines in excellent yields. The developed methods have proven to be general, fast, convenient, and economic, and thus are expected to have broad utility to efficiently construct novel compounds for future biological and chemical applications.

  • 21.
    Chow, Shiao Y.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preparative Medicinal Chemistry.
    Odell, Luke R.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preparative Medicinal Chemistry.
    Eriksson, Jonas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preparative Medicinal Chemistry.
    Low-Pressure Radical 11C-Aminocarbonylation of Alkyl Iodides through Thermal Initiation2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2017, no 8, p. 1236-1236Article in journal (Refereed)
  • 22.
    Chow, Shiao Y.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Odell, Luke R.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Eriksson, Jonas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    Low-Pressure Radical C-11-Aminocarbonylation of Alkyl Iodides through Thermal Initiation2016In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 36, p. 5980-5989Article in journal (Refereed)
    Abstract [en]

    A radical C-11-aminocarbonylation protocol characterized by excellent substrate compatibility was developed to transform alkyl iodides into C-11-labelled amides, including the 11-HSD1 inhibitor [carbonyl-C-11]adamantan-1-yl(piperidin-1-yl)methanone. This protocol serves as a complementary extension of palladium-mediated C-11-aminocarbonylation, which is limited to the preparation of C-11-labelled compounds lacking beta-hydrogen atoms. The use of AIBN as a radical initiator and a low-pressure xenon-[C-11]CO delivery unit represents a simple and convenient alternative to previous radical C-11-carbonylation methodologies burdened with the need for a proprietary high pressure reactor connected to a light source.

  • 23. Cosner, Casey C.
    et al.
    Iska, Vijaya Bhaskara Reddy
    Chatterjee, Anamitra
    Markiewicz, John T.
    Corden, Steven J.
    Löfstedt, Joakim
    Ankner, Tobias
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Richer, Joshua
    Hulett, Tyler
    Schauer, Douglas J.
    Wiest, Olaf
    Helquist, Paul
    Evolution of Concise and Flexible Synthetic Strategies for Trichostatic Acid and the Potent Histone Deacetylase Inhibitor Trichostatin A2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 1, p. 162-172Article in journal (Refereed)
    Abstract [en]

    (R)-(+)-Trichostatic acid and (R)-(+)-trichostatin A (TSA) are natural products that have attracted considerable attention in the field of epigenetic therapies. TSA in particular is a naturally occurring hydroxamic acid having potent activity as a histone deacetylase inhibitor (HDACi) and having significant potential for treatment of a myriad of genetically based diseases. Development of TSA and other trichostatic acid derivatives into useful small-molecule therapies has been hindered by the low natural abundance and high cost associated with these compounds. We report herein our collective efforts towards the development of concise and scalable routes for the synthesis of trichostatic acid and TSA in both racemic and enantioenriched forms. Three independent synthetic pathways were developed with varying degrees of efficiency and convergency. In the first synthesis, the key step was a vinylogous Horner-Wadsworth-Emmons condensation. A Marshall propargylation reaction was used as the key step in the second synthesis, and Pd-catalyzed a-alkenylation of a ketone zinc enolate by using various functionalized alkenyl or dienyl halides was developed for the third synthesis. The second pathway proved to be readily amenable to an enantioselective modification, and both the second and third pathways were straightforwardly adapted for the facile preparation of new analogues of trichostatic acid and TSA.

  • 24.
    Cumpstey, Ian
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ramstadius, Clinton
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Akhtar, Tashfeen
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Goldstein, Irwin J
    Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI .
    Winter, Harry C
    Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI .
    Non-glycosidically linked pseudodisaccharides: thioethers, sulfoxides, sulfones, ethers, selenoethers, and their binding to lectins2010In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 1951-1970Article in journal (Refereed)
    Abstract [en]

    Hydrolytically stable non-glycosidically linked tail-to-tail pseudodisaccharides are linked by a single bridging atom remote from the anomeric centre of the constituent monosaccharides. Some such pseudodisaccharides with sulfur or oxygen bridges were found to act as disaccharide mimetics in their binding to the Banana Lectin and to Concanavalin A. A versatile synthetic route to a small library of such compounds is described

  • 25.
    Dahl, Kenneth
    et al.
    Karolinska Institute, Stockholm, Sweden.
    Nordeman, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    11C-Acetylation of Amines with [11C]Methyl Iodide with Bis(cyclopentadienyldicarbonyliron) as the CO Source2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 38, p. 5785-5788Article in journal (Refereed)
    Abstract [en]

    We describe herein a novel approach for the direct 11C-acetylation of amines. The carbonylative protocol is palladium-mediated, uses bis(cyclopentadienyldicarbonyliron) as the CO source, and [11C]methyl iodide or [11C]methyl iodide-D3 as a radioactive precursor. A set of functionalized primary and secondary amines was 11C-labelled in radiochemical yields ranging from 7–85 %. The potential use of this method for positron emission tomography radiotracer production was additionally demonstrated by the radiosynthesis of [11C]lacosamide, [11C]melatonine, and [11C]acecainide in 44–55 % RCY.

  • 26.
    Dahl, Kenneth
    et al.
    Karolinska Insititute, Ctr Psychiat Res, Karolinska Hosp, Dept Clin Neurosci, SE-17176 Stockholm, Sweden..
    Nordeman, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Organic Pharmaceutical Chemistry.
    C-11-Carbonylation through in Situ Generated C-11-Benzoyl Chlorides with Tetrabutylammonium Chloride as Chloride Source2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 18, p. 2648-2651Article in journal (Refereed)
    Abstract [en]

    Aromatic C-11-containing acids, amides, esters, and aldehydes were obtained through a novel C-11-carbonylative reaction. In the two-step process, aryl iodides are first reacted with (CO)-C-11 and tetrabutylammonium chloride in a palladium-mediated reaction to yield C-11-benzoyl chlorides in situ. The crude mixture is then further treated with either a hydroxide, amine, alcohol, or a hydride in a second vial to furnish the final C-11-carbonyl product. The monodentate ligand tri-tert-butylphosphonium tetrafluoroborate was proven to be crucial for obtaining high radiochemical yields (RCY). A wide range of C-11-containing carbonyl compounds were successfully radiolabeled in moderate to excellent RCYs, ranging from 41-93%. The synthetic retinoic acid tamibarotene was obtained in a RCY of 89%, whereas the Boc-protected procainamide was labelled in 68% RCY, which is a significantly increase (2-3 fold) in RCY compared to other published methods.

  • 27.
    Danielsson, Jakob
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Toom, Lauri
    Institute of Technology, University of Tartu, Tartu, Estonia.
    Somfai, Peter
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    1,3-Dipolar Cycloaddition of Azomethine Ylides to Aldehydes: Synthesis of anti alpha-Amino-beta-Hydroxy Esters2011In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 3, p. 607-613Article in journal (Refereed)
    Abstract [en]

    A 1,3-dipolar cycloaddition reaction of azomethine ylides to aldehydes is described. The azomethine ylides, generated by thermal electrocyclic ring opening of aziridines, adds to aldehydes in good yields with moderate to good selectivities to furnish oxazolidines. The oxazolidines were subsequently hydrolyzed to the corresponding amino alcohols, giving the anti diastereomer as the major product.

  • 28. Del Litto, Raffaella
    et al.
    Benessere, Vincenzo
    Ruffo, Francesco
    Moberg, Christina
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Carbohydrate-Based Pyridine-2-carboxamides for Mo-Catalyzed Asymmetric Allylic Alkylations2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 9, p. 1352-1356Article in journal (Refereed)
    Abstract [en]

    Bis(pyridine-2-carboxamides) were prepared from 1,2-diamines obtained from alpha-D-ghlcose and alpha-D-mannose. The ligands were assessed in molybdenum-catalyzed asymmetric allylic alkylations (AAA) by using both methyl (E)-3-phenyl-2-propenyl and methyl rac-1-phenyl-2-propenyl carbonates and dimethyl malonate as nucleophile under microwave irradiation. High enantioselectivity (99 % ee) and high regioselectivity (49:1 in favour of the branched isomer) were observed in reactions of the linear achiral substrate in the presence of 10 mol-% of a catalyst prepared from a ligand derived from glucose. Somewhat lower enantioselectivity (up to 96 % ee) was observed in reactions with the branched racemic carbonate by using the same ligand. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

  • 29. Dyrager, Christine
    et al.
    Börjesson, Karl
    Dinér, Peter
    University of Gothenburg.
    Elf, A.
    Albinsson, Bo
    Wilhelmsson, Marcus
    Grøtli, Morten
    Synthesis and Photophysical Characterisation of Fluorescent 8-(1H-1,2,3-Triazol-4-yl)adenosine Derivatives2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 1515-1521Article in journal (Refereed)
  • 30.
    El Remaily, Mahmoud Abd El Aleem Ali Ali
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Sohag University, Egypt.
    Naidu, Veluru Ramesh
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ni, Shengjun
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Franzén, Johan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Carbocation Catalysis: Oxa-Diels-Alder Reactions of Unactivated Aldehydes and Simple Dienes2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 30, p. 6610-6614Article in journal (Refereed)
    Abstract [en]

    The versatility of the trityl cation (TrBF<inf>4</inf>) as a highly efficient Lewis acid organocatalyst is demonstrated in the oxa-Diels-Alder reaction of various unactivated aromatic and aliphatic aldehydes and simple unactivated dienes, such as isoprene and 2,3-dimethylbutadiene. The transformation proceeds smoothly to give 3,6-dihydropyrane adducts in high to moderate yields with catalyst loadings down to 1.0 mol-% under mild reaction conditions. In contrast to most previously reported strategies, this protocol does not require substrate functional group activation, neither by electron-deficient aldehydes (2-oxo aldehydes) or electron-rich dienes (methoxy or amino-butadiene).

  • 31.
    Engqvist, Robert
    et al.
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science. Karolinska Institutet.
    Javaid, Atif
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    Bergman, Jan
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science. Karolinska Institutet.
    Synthesis of thienodolin2004In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 12, p. 2589-2592Article in journal (Refereed)
    Abstract [en]

    We report a total synthesis of the alkaloid thienodolin (1a), as well as its 5-chloro isomer 1b and its unsubstituted analogue 1c, in three steps from the corresponding oxindoles Ba-c. The preparation was achieved through an initial Vilsmeier-Haack-Arnold reaction (chloro-formylation) followed by protection at the indole nitrogen, creation of the fused thiophene ring by nucleophilic substitution at the 2-position and an intramolecular cyclization using mercaptoacetamide. This gave 1a, 1b and 1c in total yields of 42%, 35% and 37%, respectively.

  • 32.
    Engström, Karin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Shakeri, Mozaffar
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dynamic Kinetic Resolution of β-Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A2011In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 1827-1830Article in journal (Refereed)
    Abstract [en]

    A dynamic kinetic resolution (DKR) of β-amino esters have been developed by the use of a heterogeneous racemization catalyst and an immobilized enzyme that accepts aromatic, heteroaromatic and aliphatic substrates. The reaction conditions were optimized to yield an efficient catalytic system without by-product formation. The products are obtained in 96–99 % ee and high yields

  • 33.
    Eriksson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Åberg, Ola
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Synthesis of [11C]/[13C]acrylamides by palladium-mediated carbonylation2007In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 3, p. 455-461Article in journal (Refereed)
    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.

  • 34. Eriksson, Kristofer
    et al.
    Verho, Oscar
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Oscarsson, Sven
    Backvall, Jan-E.
    Dispersed Gold Nanoparticles Supported in the Pores of Siliceous Mesocellular Foam: A Catalyst for Cycloisomerization of Alkynoic Acids to gamma-Alkylidene Lactones2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 2250-2255Article in journal (Refereed)
    Abstract [en]

    A versatile approach for the production of dispersed thiol-stabilized gold nanoparticles in the pores of siliceous mesocellular foam (MCF) is described. The reported method is based on an electrochemical oxidation of a gold surface generating oxidative Au-III species, which give rise to a surface-confined redox reaction yielding MCF-supported Au-I thiolates. By reducing the corresponding Au-I-S-MCF species with sodium borohydride, thiol-stabilized gold nanoparticles in the size range of 1-8 nm were obtained as determined by transmission electron microscopy. Elemental analysis indicated an Au loading of 3% (w/w) on the MCF. The surface-confined Au nanoparticles were used to catalyze the cycloisomerization of alkynoic acids to the corresponding -alkylidene lactones in high efficiency and complete 5-exo-dig selectivity under mild reaction conditions.

  • 35.
    Eriksson, Kristofer
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Verho, Oscar
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Nyholm, Leif
    Oscarsson, Sven
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dispersed Gold Nanoparticles Supported in the Pores of Siliceous Mesocellular Foam: A Catalyst for Cycloisomerization of Alkynoic Acids to gamma-Alkylidene Lactones2015In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 2250-2255Article in journal (Refereed)
    Abstract [en]

    A versatile approach for the production of dispersed thiol-stabilized gold nanoparticles in the pores of siliceous mesocellular foam (MCF) is described. The reported method is based on an electrochemical oxidation of a gold surface generating oxidative Au-III species, which give rise to a surface-confined redox reaction yielding MCF-supported Au-I thiolates. By reducing the corresponding Au-I-S-MCF species with sodium borohydride, thiol-stabilized gold nanoparticles in the size range of 1-8 nm were obtained as determined by transmission electron microscopy. Elemental analysis indicated an Au loading of 3% (w/w) on the MCF. The surface-confined Au nanoparticles were used to catalyze the cycloisomerization of alkynoic acids to the corresponding -alkylidene lactones in high efficiency and complete 5-exo-dig selectivity under mild reaction conditions.

  • 36. Eriksson, P.
    et al.
    Engman, L.
    Lind, Johan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Nuclear Chemistry.
    Merenyi, Gabor
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Nuclear Chemistry.
    Aqueous phase one-electron reduction of sulfonium, selenonium and telluronium salts2005In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 4, p. 701-705Article in journal (Refereed)
    Abstract [en]

    Triorganylsulfonium, -selenonium and -telluronium salts were reduced by carbon dioxide radical anions/solvated electrons produced in aqueous solution by radiolysis. The radical expulsion accompanying reduction occurred with the expected leaving group propensities (benzyl > secondary alkyl > primary alkyl > methyl > phenyl), although greater than expected loss of the phenyl group was often observed. Diorganyl chalcogenides formed in the reductions were conveniently isolated by extraction with an organic solvent. Product yields based on the amount of reducing radicals obtained from the T-source were often higher than stoichiometric (up to 1800 %) in the reduction of selenonium and telluronium compounds; it is likely that this result can be accounted for in terms of a chain reaction with carbon-centred radicals/formate serving as the chain transfer agent. The product distribution was essentially independent of the reducing species for diphenyl alkyl telluronium salts, whereas significant variations were seen for some of the corresponding selenonium salts. This would suggest the intermediacy of telluranyl radicals in the one-electron reduction of telluronium salts. However, pulse radiolysis experiments indicated that the lifetimes of such a species (the triphenyltelluranyl radical) would have to be less than 1 mus.

  • 37.
    Frigell, Jens
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pearcey, Jean A.
    Lowary, Todd L.
    Cumpstey, Ian
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabinogalactan2011In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 7, p. 1367-1375Article in journal (Refereed)
    Abstract [en]

    A partially protected carbasugar analogue of beta-galactofuranose was converted into an alpha-galacto-configured 1,2-epoxide, which was opened by alcohols under Lewis acid catalysis with regioselective attack at C-1 to give beta-galacto-configured C-1 ethers. Using OH-5 and OH-6 carbagalactofuranose derivatives as nucleophiles, we synthesised pseudodisaccharide analogues of substructures of the arabinogalactan from M. tuberculosis. The dicarba analogue of the disaccharide Galf(beta 1 -> 5) Galf was found to moderately inhibit the action of GlfT2 galactofuranosyl transferase from M. tuberculosis.

  • 38.
    Ghirmai, Senait
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Mume, Eskender
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Henssen, Cecile
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Ghaneolhusseini, Hadi
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Lundqvist, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Tolmachev, Vladimir
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Sjöberg, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Orlova, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Synthesis and Radioiodination of Some 9-Aminoacridine Derivatives2004In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 17, p. 3719-3725Article in journal (Refereed)
  • 39.
    Hellberg, Jonas
    et al.
    KTH, Superseded Departments, Chemistry.
    Dahlstedt, Emma
    KTH, Superseded Departments, Chemistry.
    Woldegiorgis, Andreas
    KTH, Superseded Departments, Chemistry.
    Umpolung of the 5-alkyl-2-dimethylamino-1,3-dithiolium-4-thiolate mesoion and its application in the synthesis of some new tetrathiafulvalenes2004In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 7, p. 1455-1463Article in journal (Refereed)
    Abstract [en]

    The 5-alkyl-2-dimethylamino-1,3-dithiolium-4-thiolate mesoion could be umpoled with sulfuryl chloride to yield a dicationic electrophile 3 that reacted with various electron-rich aromatic substrates to yield arylthio-substituted 1,3-dithiolium salts 13-25. Two of these compounds have been transformed to the corresponding symmetrical tetrathiafulvalenes 43 and 44, and their cyclovoltammetric behaviour recorded.

  • 40.
    Hirner, Sebastian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kirchner, Donata Katharina
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Somfai, Peter
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Synthesis of alpha-Amino Acids by Umpolung of Weinreb Amide Enolates2008In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 33, p. 5583-5589Article in journal (Refereed)
    Abstract [en]

    An efficient and diastereoselective synthesis of alpha-amino acids from readily available starting materials has been developed. The key feature of this reaction is an umpolung of a glycine-derived enolate, providing an alternative approach for the synthesis of alpha-amino acids.

  • 41.
    Horváth, Attila
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-Erling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Benner, Jessica
    Simple, Enantiocontrolled Synthesis of 3-Pyrrolines from α-Amino Allenes2004In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2004, no 15, p. 3240-3243Article in journal (Refereed)
    Abstract [en]

    Cyclization of -amino allenes in the presence of N-bromosuccinimide afforded pyrrolines in good yields. The products were obtained with high enantiomeric excesses when optically active allenes were used as substrates. The synthesis of a 2,5-dehydroprolinol derivative is also presented.

  • 42.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Blom, Elisabeth
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Kihlberg, Tor
    The Use of Lithium Amides in the Palladium-Mediated Synthesis of [Carbonyl-11C]Amides2007In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2007, no 26, p. 4337-4342Article in journal (Refereed)
    Abstract [en]

    Weakly nucleophilic amines were converted into the corresponding lithium amides and used in either one- or two-pot palladium mediated-reactions with [11C]carbon monoxide and aryl iodides. It was found that palladium acyl complexes may be prepared in a separate step and have sufficient lifetime to be used in a subsequent reaction with a nucleophile. This two-pot procedure was used for the labelling synthesis of eleven amides (nine of which are analogues of WAY-100635, a 5-HT1A radioligand) from weakly nucleophilic amines. The results were compared to a direct one-pot procedure using lithium amides. Both approaches extend the scope of palladium-mediated carbonylation using [11C]carbon monoxide and aryl iodides allowing use of weakly nucleophilic amines.

  • 43.
    Janosik, Tomasz
    et al.
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Bergman, Jan
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Romero, Ivan
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Stensland, B
    Stålhandske, C
    Marques, M M B
    Santos, M M M
    Lobo, A M
    Prabhakar, S
    Duarte, M F
    Florencio, M H
    Synthetic, spectroscopic, and X-ray crystallographic studies of [1,2,7,8]tetrathiacyclododecino[4,3-b: 5,6-b': 10,9-b": 11,12-b''']tetraindoles2002In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 8, p. 1392-1396Article in journal (Refereed)
    Abstract [en]

    Two conformationally different [1,2,7,8]tetrathiacyclododecino[4,3-b:5,6-b':10,9-b":11,12-b''']tetraind oles 9a and 9b have been isolated in good yields, and the existence of a third conformer 9c in solution was demonstrated by mass spectrometry and H-1 NMR spectroscopy. The interconversions of the tetraindoles 9a-c have also been studied. The conformation of 9b was confirmed by X-ray crystallography, while the conformations of 9a and 9b were assigned on the basis of spectroscopic data, and were also supported by molecular modelling studies. In addition, the elusive dithiin 3 was isolated and the structure was proven by X-ray crystallography.

  • 44.
    Jiang, Yan
    et al.
    Stockholm University, Stockholm.
    Deiana, Luca
    Stockholm University, Stockholm.
    Alimohammadzadeh, Rana
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences. Stockholm University, Stockholm.
    Liu, Leifeng
    Stockholm University, Stockholm.
    Sun, Junliang
    Stockholm University, Stockholm.
    Córdova, Armando
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences. Stockholm University, Stockholm.
    Highly Diastereo- and Enantioselective Cascade Synthesis of Bicyclic Lactams in One-Pot2018In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2018, no 9, p. 1158-1164Article in journal (Refereed)
    Abstract [en]

    A versatile and highly stereoselective synthetic route to functionalized bi- and tricyclic lactams (up to > 20:1 dr and 99 % ee) in one pot from simple starting materials (allylic alcohols, enals, diamines and amino alcohols) using cascade transformations promoted by chiral amine/Brønsted or metal/chiral amine/Brønsted relay catalysis is disclosed. Here molecular oxygen is employed as the terminal oxidant for the latter relay catalysis approach. 

  • 45.
    Jiang, Yan
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Alimohammadzadeh, Rana
    Liu, Leifeng
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Mid Sweden University, Sweden.
    Highly Diastereo- and Enantioselective Cascade Synthesis of Bicyclic Lactams in One-Pot2018In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 9, p. 1158-1164Article in journal (Refereed)
    Abstract [en]

    A versatile and highly stereoselective synthetic route to functionalized bi- and tricyclic lactams (up to > 20:1 dr and 99% ee) in one pot from simple starting materials (allylic alcohols, enals, diamines and amino alcohols) using cascade transformations promoted by chiral amine/BrOnsted or metal/chiral amine/BrOnsted relay catalysis is disclosed. Here molecular oxygen is employed as the terminal oxidant for the latter relay catalysis approach.

  • 46.
    Jiang, Yan
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhang, Kaiheng
    Lin, Shuangzheng
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Mid Sweden University, Sweden.
    Total Asymmetric Synthesis of Quinine, Quinidine, and Analogues via Catalytic Enantioselective Cascade Transformations2019In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 35, p. 6016-6023Article in journal (Refereed)
    Abstract [en]

    A catalytic asymmetric strategy for the total synthesis of quinuclidine natural products, which includes the completed enantioselective synthesis of the classical targets quinine and quinidine is disclosed. It is based on catalytic asymmetric cascade transformations, which paves the road for the synthesis of both enantiomers of the crucial C4 stereocenter with high enantioselectivity (up to 99 % ee) in one pot. Next, developing a route to all possible stereoisomers of a common early-stage intermediate sets the stage for the total synthesis of different enantiomers or epimers of quinine, quinidine and analogues with high selectivity.

  • 47.
    Jiang, Yan
    et al.
    Stockholm University, Stockholm.
    Deiana, Luca
    Stockholm University, Stockholm.
    Zhang, Keihang
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Lin, Shuangzheng
    Stockholm University, Stockholm.
    Córdova, Armando
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Total Asymmetric Synthesis of Quinine, Quinidine, and Analogues via Catalytic Enantioselective Cascade Transformations2019In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 35, p. 6016-6023Article in journal (Refereed)
    Abstract [en]

    A catalytic asymmetric strategy for the total synthesis of quinuclidine natural products, which includes the completed enantioselective synthesis of the classical targets quinine and quinidine is disclosed. It is based on catalytic asymmetric cascade transformations, which paves the road for the synthesis of both enantiomers of the crucial C4 stereocenter with high enantioselectivity (up to 99 % ee) in one pot. Next, developing a route to all possible stereoisomers of a common early-stage intermediate sets the stage for the total synthesis of different enantiomers or epimers of quinine, quinidine and analogues with high selectivity. 

  • 48. Jogula, Srinivas
    et al.
    Dasari, Bhanudas
    Khatravath, Mahender
    Chandrasekar, Gayathri
    Kitambi, Satish Srinivas
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies. Karolinska institutet.
    Arya, Prabhat
    Building a Macrocyclic Toolbox from C-Linked Carbohydrates Identifies Antiangiogenesis Agents from Zebrafish Assay2013In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2013, no 23, p. 5036-5040Article in journal (Refereed)
    Abstract [en]

    We report the synthesis of four different types of macrocyclic-derived glycohybrids from carbohydrates that have an amino acid moiety in the large-ring skeleton. These macrocyclic glycohybrids were obtained from -C-1H- and -C-1H-linked carbohydrates. In one series, we utilized ring-closing metathesis as the stitching technology to obtain two different macrocycles, i.e., trans equatorial-axial C-1H and C-5H and cis axial-axial C-1H and C-5H. The click approach was the key reaction in our second series to obtain two other macrocyclic compounds, i.e., trans equatorial-axial C-1H and C-5H and cis axial-axial C-1H and C-5H. The evaluation of this toolbox resulted in the identification of two unique compounds as antiangiogenesis agents in an embryonic zebrafish assay. Interestingly, in both cases, the macrocyclic compounds that have a cis relationship (i.e., axial-axial orientation) between C-1H and C-5H showed activity and their other diastereomers (i.e., equatorial-axial C-1H and C-5 H) with a trans relationship did not show any effect.

  • 49.
    Johnston, Eric V.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Karlsson, Erik A.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Tran, Lien-Hoa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Åkermark, Björn
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient aerobic ruthenium-catalyzed oxidation of secondary alcohols by the use of a hybrid electron transfer catalyst2010In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 10, p. 1971-1976Article in journal (Refereed)
    Abstract [en]

    Biomimetic aerobic oxidation of secondary alcohols has been performed using hybrid catalyst 1 and Shvo's catalyst 2. This combination allows mild reaction conditions and low catalytic loading, due to the efficiency of intramolecular electron transfer. By this method a wide range of different alcohols have been converted into their corresponding ketones. Oxidation of benzylic as well as aliphatic, electron-rich, electron-deficient and sterically hindered alcohols could be oxidized in excellent yield and selectivity. Oxidation of (S)-1-phenyl-ethanol showed that no racemization occurred during the course of the reaction, indicating that the hydride 2b adds to the quinone much faster than it re-adds to the ketone product. The kinetic deuterium isotope effect of the oxidation was determined by the use of 1-phenylethanol (3a) and 1-deuterio-1-phenylethanol (3a-d1) in parallel and competitive manner, which gave the same isotope effect within experimental error (k(H)/k(D) approximate to 2.8). This indicates that there is no strong coordination of the substrate to the catalyst.

  • 50.
    Johnston, Eric V.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Karlsson, Erik A.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Tran, Lien-Hoa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Åkermark, Björn
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient synthesis of hybrid (hydroquinone-Schiff base)cobalt oxidation catalysts2009In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 23, p. 3973-3976Article in journal (Refereed)
    Abstract [en]

    Hybrid catalysts A and B have recently been found to efficiently transfer electrons from a metal catalyst to molecular oxygen in biomimetic oxidations. In the present work hybrid catalysts A and B were synthesized in high yield from inexpensive starting materials. The key step is an efficient Suzuki cross-coupling, which allows the use of unprotected aldehyde 5. The new synthesis of the title hybrid catalysts is easy to carry out and can be scaled up.

123 1 - 50 of 120
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