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  • 151.
    Antoni G., Ögren M., Långström B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Enzymes as catalysts in labelling synthesis using short-lived radionuclides2001Inngår i: Synthesis and Applications of Isotopically LabelledArtikkel i tidsskrift (Fagfellevurdert)
  • 152.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Kihlberg, T.
    Långström, B.
    11C: Labelling chemistry and labelled compounds2003Inngår i: Handbook Chem03_0302, 2003, nr 332, s. 119-165Kapittel i bok, del av antologi (Fagfellevurdert)
  • 153.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Långström, Bengt
    Asymmetric synthesis of L-2-amino[3-11C]butyric acid, L-[3-11C]norvaline and L-[3-11C]valine.1987Inngår i: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. B41, s. 511-Artikkel i tidsskrift (Fagfellevurdert)
  • 154.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Långström, Bengt
    Synthesis of DL-11C-labelled alanine, 2-aminobutyric acid, norvaline, leucine and phenylalanine and preparation of L-[3-11C]alanine and L-[3-11C]phenylalanine.1987Inngår i: Journal of labelled compounds & radiopharmaceuticals, ISSN ISSN 0362-4803, EISSN 1099-1344, Vol. 24, s. 125-Artikkel i tidsskrift (Fagfellevurdert)
  • 155.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Långström, Bengt
    Synthesis of DL-[3-11C]valine using [2-11C]isopropyl iodide and preparation of L-[3-11C]valine by treatment with D-amino acid oxidase.1987Inngår i: Int. J. Appl. Radiat. Isot., Vol. 38, s. 655-Artikkel i tidsskrift (Fagfellevurdert)
  • 156.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Långström, Bengt
    Synthesis of gamma-amino[4-11C]butyric acid.1989Inngår i: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 27, s. 571-Artikkel i tidsskrift (Fagfellevurdert)
  • 157.
    Antoni, Gunnar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Ulin, Johan
    Långström, Bengt
    Synthesis of the 11C-labelled b-adrenargic receptor ligands atenolol, metoprolol and propranol.1989Inngår i: The international journal of applied radiation and isotopes, ISSN 0020-708X, E-ISSN 1878-1284, Vol. 40, s. 561-Artikkel i tidsskrift (Fagfellevurdert)
  • 158.
    Antonsson, Cecilia
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Mjölk, gluten och ADHD: En litteraturundersökning om mjölk och glutens påverkan hos barn med ADHD2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Attention Deficit Hyperactivity Disorder (ADHD) is becoming a more common diagnosis of younger children. In recent years the perception that some ingredients in our food may have a negative effect regarding the symptoms in children with ADHD has grown stronger. Children with ADHD often suffer from irritated bowel syndromes which affect their ability to digest food. This may result in malnutrition as well as a release of substances that are harmful.The purpose of this report is to compile and illustrate the knowledge of how special food, particular milk protein and gluten, may affect the symptoms of children with ADHD. Also, the report aims to evaluate if there should be changes made in Kindergarten to increase the well-being of these children. The report is a summary of research results on the effects milk protein and gluten have on children with ADHD.The majority of children with ADHD demonstrate decreased symptoms if they receive a diet without milk protein and gluten.If children with ADHD would be given a special diet excluding milk protein and gluten it is realistic to assume that their ADHD-symptoms might be reduced with a greater sense of well-being and quality of life as a result.

  • 159.
    Appukkuttan, Prasad
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Axelsson, Linda
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Van der Eycken, Erik
    Larhed, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Microwave-assisted, Mo(CO)(6)-mediated, palladium-catalyzed amino-carbonylation of aryl halides using allylamine: from exploration to scale-up2008Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 49, nr 39, s. 5625-5628Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Palladium-catalyzed aminocarbonylations of various (hetero)aryl halides with allylamine using Mo(CO)(6) as a solid, in situ CO source, were explored. Microwave-enhanced conditions proved to be highly useful in promoting the conversions in a mere 10-20 min with various (hetero)aryl iodides, bromides and chlorides. The scale-up of a microwave-enhanced aminocarbonylation to 25 mmol scale was performed successfully. (C) 2008 Elsevier Ltd. All rights reserved.

  • 160.
    Arafa, Wael A. A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kärkäs, Markus D.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Lee, Bao-Lin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Åkermark, Torbjörn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liao, Rong-Zhen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Berends, Hans-Martin
    Messinger, Johannes
    Siegbahn, Per E. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Dinuclear manganese complexes for water oxidation: evaluation of electronic effects and catalytic activity2014Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 16, nr 24, s. 11950-11964Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During recent years significant progress has been made towards the realization of a sustainable and carbon-neutral energy economy. One promising approach is photochemical splitting of H2O into O-2 and solar fuels, such as H-2. However, the bottleneck in such artificial photosynthetic schemes is the H2O oxidation half reaction where more efficient catalysts are required that lower the kinetic barrier for this process. In particular catalysts based on earth-abundant metals are highly attractive compared to catalysts comprised of noble metals. We have now synthesized a library of dinuclear Mn-2 (II,III) catalysts for H2O oxidation and studied how the incorporation of different substituents affected the electronics and catalytic efficiency. It was found that the incorporation of a distal carboxyl group into the ligand scaffold resulted in a catalyst with increased catalytic activity, most likely because of the fact that the distal group is able to promote proton-coupled electron transfer (PCET) from the high-valent Mn species, thus facilitating O-O bond formation.

  • 161. Arafa, Wael A. A.
    et al.
    Mohamed, Ashraf M.
    Abdel-Magied, Ahmed F.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    ULTRASOUND-MEDIATED THREE-COMPONENT REACTION ON-WATER PROTOCOL FOR THE SYNTHESIS OF NOVEL MONO- AND BIS-1,3-THIAZIN-4-ONE DERIVATIVES2017Inngår i: Heterocycles, ISSN 0385-5414, E-ISSN 1881-0942, Vol. 94, nr 8, s. 1439-1455Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Green synthetic and catalyst-free strategy towards the synthesis of novel mono- and bis-1,3-thiazin-4-one scaffolds through a one pot, reaction of carbon disulfide, monoacetylenic esters and amines under ultrasonication has been reported. The merits of this protocol comprise no need for tedious workup steps and afforded the desired products in excellent yields make this synthetic protocol more efficient and worthy of further attentiveness. Moreover, the method exhibited excellent score in a number of green metrics.

  • 162. Arafa, Wael Abdelgayed Ahmed
    et al.
    Abdel-Magied, Ahmed Fawzy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Nuclear Material Authority, Egypt.
    Utilization of ultrasonic irradiation as green and effective one-pot protocol to prepare a novel series of bis-2-amino-1,3,4-oxa(thia) diazoles and bis-tetrazoles2017Inngår i: ARKIVOC, ISSN 1551-7004, E-ISSN 1551-7012, s. 327-340Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In an effective and straightforward conversion, bis-semicarbazones and bis-thiosemicarbazones are transformed into a diversity of novel substituted bis-2-amino-1,3,4-oxadiazoles and bis-2-amino-1,3,4-thiadiazoles, respectively under ultrasonic irradiation. Bis-tetrazoles are obtained from the dialdehydes by sequential reaction with hydroxylamine hydrochloride, phosphorus pentoxide and sodium azide without isolation of the intermediates oximes and nitriles. All the reactions proceed cleanly and smoothly under mild conditions, with short reaction times and broad functional groups possibility. No side reactions were observed. [GRAPHICS]

  • 163.
    Arefalk, Anna
    Uppsala universitet, Medicinska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    New Methods for the Synthesis of 3-Substituted 1-Indanones: A Palladium-Catalyzed Approach2005Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In medicinal chemistry, there is a constant need for new preparative methods, both to make the synthesis process more effective, and to increase the accessibility to a wide variety of compounds. A number of different approaches can be used to attain these goals. Transition metal catalysis is generally performed under mild conditions, providing both regio- and chemoselective reactions. Thus, it offers an attractive means of preparation of complex drug candidates. Two additional methodologies used to increase the preparative efficiency are one-pot protocols and controlled microwave heating. One-pot and multi-component reactions are less time consuming than step-by-step reactions, and microwave heating has been used to considerably shorten the reaction times.

    This thesis describes a new palladium-catalyzed, one-pot reaction producing racemic acetal-protected 3-hydroxy-1-indanones from ethylene glycol vinyl ether and triflates of salicylic aldehydes. The triflates were prepared using controlled microwave heating. The reaction sequence starts with a regioselective internal Heck coupling, followed by an annulation cascade. By including secondary amines in the reaction mixture, the reaction was further developed into a three-component reaction delivering racemic acetal-protected 3-amino-1-indanones. This new method was utilized for the synthesis of primary, secondary and tertiary aminoindanones. Finally, by using enantiopure t-butyl sulfinyl imines, derived from salicylic aldehyde triflates and ethylene glycol vinyl ether as starting materials in a closely related type of palladium coupling–annulation sequence, a stereoselective protocol providing enantiomerically pure 3-amino-1-indanones was developed. To demonstrate an application in medicinal chemistry, the enantiopure 3-amino-1-indanones were incorporated as P2 and/or P2´ substituents into active HIV-1 protease inhibitors.

  • 164.
    Arja, Katriann
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Multimodal Porphyrin-Based Conjugates: Synthesis and characterization for applications as amyloid ligands, photodynamic therapy agents and chiroptical materials2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Organic compounds that interact both with certain biological targets and display specific photophysical properties can be utilized as molecular tools to visualize and possibly effect disease related processes taking place in living organisms. In this regard, porphyrins are a class of naturally occurring molecules that possess intriguingly interesting photophysical properties where they can act as luminescent probes by emitting detectable light, as well as photosensitizers in the light mediated therapy called photodynamic therapy. In this thesis, the porphyrin structure has been synthetically combined with other molecule classes to achieve compounds with desirable multimodal characteristics.

    Firstly, luminescent conjugated oligothiophenes (LCOs) that have extensively, and with great success, been utilized as fluorescent ligands for amyloid formations, have been conjugated to porphyrins to render oligothiophene porphyrin hybrids (OTPHs) comprising two optically active modalities. When applied as fluorescent amyloidophilic dyes for visualization of amyloid-β (Aβ), one of the pathological hallmarks in Alzheimer’s disease, an enhanced optical assignment of distinct aggregated forms of Aβ was afforded.  Thus, properly functionalized OTPHs could give us more information about pathological processes underlying devastating disorders, such as Alzheimer’s disease. In addition, the OTPHs can be associated with synthetic peptides inducing peptide folding into certain three-dimensional helical structures giving rise to novel optically active materials.

    Secondly, this thesis also embraces porphyrins’ potential as photosensitizers in photodynamic therapy to kill cancer cells. Grounded on the prerequisites for an optimal photosensitizer, we designed porphyrin-based conjugates equipped with common carbohydrates for improved cancer cell selectivity and with a fluorinated glucose derivative, 2-fluoro 2-deoxy glucose, for advantageous metabolism in cancer cells. Furthermore, incorporation of a radioisotopic fluorine-18 atom into the glycoporphyrins could give the means for diagnostic use of the conjugates in positron emission tomography (PET).

    In order to tether together the above-mentioned molecular moieties in a controlled fashion, we developed a robust synthetic strategy for asymmetrical functionalization of porphyrin core. The method involves chlorosulfonation of this otherwise inert tetrapyrrolic structure, followed by alkynylation. Parallelly to amide coupling reactions, copper(I)-catalyzed alkyne azide cycloaddition is used for fast and high-yielding late-stage conjugations. Overall, this thesis demonstrates how combining different molecular moieties in synthetic organic chemistry yields novel molecules with combined and improved multimodal properties for biological and medicinal applications, guided by the design-by-function methodology.      

  • 165.
    Arkhypchuk, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Novel Approaches to Phosphorus-containing Heterocycles and Cumulenes2013Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Fast development in all areas of life and science over the last 50 years demands versatile, energy efficient and cheap materials with specific but easily tuneable properties which can be used for example in organic light emitting diodes (OLEDs), thin-film transistors, photovoltaic cells, etc. This thesis is devoted to the development of novel synthetic approaches to molecules with potential applications in the field of molecular electronics.  The acquisition of a detailed mechanistic understanding of the newly developed reactions is central to the work presented in this thesis.

    The first chapter is dedicated to the development of a new procedure for the preparation of phospha-Wittig-Horner (pWH) reagents, i.e. a reagents that has been known to convert carbonyl compounds into compounds with P=C double bonds. Each step of the synthetic sequence, i.e. preparation of the starting P,P-dichlorophosphines, their phosphorylation using the Michaelis-Arbuzov protocol, coordination to the metal centre and final hydrolysis, are presented in detail. A possible route to uncoordinated pWH reagents is also discussed.

    The second chapter focuses on the reactivity of the pWH reagents with acetone under different reaction conditions. The results show how changes in the ratio of starting material vs. base as well as reaction time or structure of the pWH reagent can influence the reaction outcome and the stability of the obtained products. The possibility to prepare unusual phosphaalkenes with unsaturated P-substituents is presented.

    The third chapter of the thesis is dedicated to the reactivity of pWH reagents towards symmetric and asymmetric ketones which contain one or two acetylene units. The proposed mechanisms of the reactions are studied by means of in situ FTIR spectroscopy as well as theoretical calculations. Physical-chemical properties of oxaphospholes, cumulenes and bisphospholes are presented.

    The last chapter is dedicated to reactivity studies of pWH reagents towards ketenes, and the exploration of a reliable route to 1-phosphaallenes. Detailed mechanistic studies of the pWH reaction that are based on the isolation and crystallographic characterization of unique reaction intermediates are presented. The reactivity of phosphaallenes towards nucleophiles such as water and methanol are examined.

    In summary, this thesis presents synthetic routes to novel phosphorus-containing molecules, together with detailed studies of the reaction mechanisms of the observed transformations.

  • 166.
    Arkhypchuk, Anna I.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    D'Imperio, Nicolas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Ott, Sascha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    One-Pot Intermolecular Reductive Cross-Coupling of Deactivated Aldehydes to Unsymmetrically 1,2-Disubstituted Alkenes2018Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 20, nr 17, s. 5086-5089Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The phospha-Peterson reaction between a lithiated secondary phosphane, MesP(Li)TMS, and an aldehyde affords Mes-phosphaalkenes which, upon methanol addition and P-oxidation, react with a second carbonyl compound site specifically to produce unsymmetric alkenes. The E/Z selectivity of the one-pot cross coupling is largely determined by the electronic nature of the aryl substituent of the first aldehyde, with electron-donating groups giving rise to increased amounts of Z-alkenes.

  • 167.
    Arkhypchuk, Anna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Mihali, Viorica Alina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström.
    Orthaber, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Ehlers, Andreas
    VU University Amsterdam.
    Lammertsma, Koop
    VU University Amsterdam.
    Ott, Sascha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Phosphorus Heterocylces from Phosphinophosphonates and α,β-Unsaturated KetonesManuskript (preprint) (Annet vitenskapelig)
  • 168.
    Arkhypchuk, Anna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Svyaschenko, Yurii
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Orthaber, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Ott, Sascha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Mechanism of the Phospha-Wittig-Horner Reaction2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 25, s. 6484-6487Artikkel i tidsskrift (Fagfellevurdert)
  • 169. Aronsson, Per
    et al.
    Munissi, Joan J E
    Gruhonjic, Amra
    Fitzpatrick, Paul A
    Landberg, Göran
    Nyandoro, Stephen S
    Erdelyi, Mate
    Phytoconstituents with Radical Scavenging and Cytotoxic Activities from Diospyros shimbaensis.2016Inngår i: Diseases (Basel, Switzerland), ISSN 2079-9721, Vol. 4, nr 1, artikkel-id E3Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As part of our search for natural products having antioxidant and anticancer properties, the phytochemical investigation of Diospyros shimbaensis (Ebenaceae), a plant belonging to a genus widely used in East African traditional medicine, was carried out. From its stem and root barks the new naphthoquinone 8,8'-oxo-biplumbagin (1) was isolated along with the known tetralones trans-isoshinanolone (2) and cis-isoshinanolone (3), and the naphthoquinones plumbagin (4) and 3,3'-biplumbagin (5). Compounds 2, 4, and 5 showed cytotoxicity (IC50 520-82.1 μM) against MDA-MB-231 breast cancer cells. Moderate to low cytotoxicity was observed for the hexane, dichloromethane, and methanol extracts of the root bark (IC50 16.1, 29.7 and > 100 μg/mL, respectively), and for the methanol extract of the stem bark (IC50 59.6 μg/mL). The radical scavenging activity of the isolated constituents (1-5) was evaluated on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The applicability of the crude extracts and of the isolated constituents for controlling degenerative diseases is discussed.

  • 170. Arukuusk, Piret
    et al.
    Pärnaste, Ly
    Hällbrink, Mattias
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Langel, Ülo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi. Tartu University, Estonia.
    PepFects and NickFects for the Intracellular Delivery of Nucleic Acids2015Inngår i: Cell-Penetrating Peptides: Methods and Protocols / [ed] Ülo Langel, New York: Springer, 2015, Vol. 1324, s. 303-315Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Nucleic acids can be utilized in gene therapy to restore, alter, or silence gene functions. In order to reveal the biological activity nucleic acids have to reach their intracellular targets by passing through the plasma membrane, which is impermeable for these large and negatively charged molecules. Cell-penetrating peptides (CPPs) condense nucleic acids into nanoparticles using non-covalent complexation strategy and mediate their delivery into the cell, whereas the physicochemical parameters of the nanoparticles determine the interactions with the membranes, uptake mechanism, and subsequent intracellular fate. The nanoparticles are mostly internalized by endocytosis that leads to the entrapment of them in endosomal vesicles. Therefore design of new CPPs that are applicable for non-covalent complex formation strategy and harness endosomolytic properties is highly vital. Here we demonstrate that PepFects and NickFects are efficient vectors for the intracellular delivery of various nucleic acids.This chapter describes how to form CPP/pDNA nanoparticles, evaluate stable nanoparticles formation, and assess gene delivery efficacy.

  • 171.
    Arvidsson P., Frackenpohl J., Ryder N., Liechty B., Petersen F., Zimmermann H., Camenisch G., Woessner R., Seebach D.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    On the antimicrobial and hemolytic activities of amphiphilic B-peptides.2001Inngår i: ChemBioChem, nr 2(10), s. 771-773Artikkel i tidsskrift (Fagfellevurdert)
  • 172.
    Arvidsson P., Ruepling M., Seebach D.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Design, machine synthesis, and NMR-solution structure of a B-heptapeptide forming a saltbridge stabilized 314-helix in methanol and in water2001Inngår i: Chemical Communications (Cambridge, U K), s. 649-650Artikkel i tidsskrift (Fagfellevurdert)
  • 173.
    Arvidsson, Per
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen. Institutionen för biokemi och organisk kemi, Organisk kemi I.
    Frackenpohl, J
    Seebach, D
    Syntheses an CD-Spectroscopic Investigations of Longer-Chain B-Peptides: Preparation by Solid-Phase Couplings of Single Amino Acids, Dipeptides, and Tripeptides2003Inngår i: Helvetica Chemica Acta, nr 86, s. 1552-1553Artikkel i tidsskrift (Fagfellevurdert)
  • 174.
    Arvidsson, Per
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen. Institutionen för biokemi och organisk kemi, Organisk kemi II.
    Ryder, N
    Weiss, M
    Gross, G
    Kretz, O
    Woessner, R
    Seebach, D
    Antibiotic and Hemolytic Activity of a B2/B3 Peptide Capable of Folding into a 12/10-Helical Secondary Structure2003Inngår i: ChemBioChem, nr 4, s. 1345-1347Artikkel i tidsskrift (Fagfellevurdert)
  • 175.
    Arvidsson, Per
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen. Institutionen för biokemi och organisk kemi, Organisk kemi I. Organisk kemi.
    Ryder, Neil S.
    Weiss, H. Markus
    Hook, David F.
    Escalante, Jaime
    Seebach, Dieter
    Exploring the Antibacterial and Hemolytic Activity of Shorter- and Longer-Chain B-, a,B-, and y-Peptides, and of B-Peptides from B2-3-Aza- and B3-2-Methylidene-amino Acids Bearing Proteinogenic Side Chains - A Survey2005Inngår i: Chemistry & Biodiversity, Vol. 2, s. 401-420Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The antibacterial activities of 31 different b-, mixed a/B-, and y-peptides, as well as of B-peptides derived from B2-3-aza- and B3-2-methylidene-amino acids were assayed against six pathogens (Enterococcus faecails, STaphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa), and the results were compared with literature data. The interaction of these peptides with mammalian cells, as modeled by measuring the hemolysis of human erythrocytes, was also investigated. In addition to those peptides designed to fold into amphiphilic helical conformations with positive charges on one face of the helix, one new peptide with hemolytic activity was detected within the sample set. Moreover, it was demontrated that neither cationic peptides used for membrane translocation (B3-oligoarginines), nor mixeda/B- or y-peptides with somatostatin-mimicking activities display unwanted hemolytic activity.

  • 176. Ashitani, T.
    et al.
    Kusumoto, N.
    Borg-Karlson, Anna Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fujita, K.
    Takahashi, K.
    Antitermite activity of β-caryophyllene epoxide and episulfide2013Inngår i: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 68 C, nr 7-8, s. 302-306Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Caryophyllene-6,7-epoxide and caryophyllene-6,7-episulfide can be easily synthesized from β-caryophyllene by autoxidation or episulfidation. The bioactivities of β-caryophyllene and its derivatives were investigated against the subterranean termite Reticulitermes speratus Kolbe. The antifeedant, feeding, and termiticidal activities of each compound were tested using no-choice, dual-choice, and non-contact methods. Antitermitic activities were not shown by β-caryophyllene, but were observed for the oxide and sulfide derivatives. Caryophyllene- 6,7-episulfide showed especially high antifeedant and termiticidal activities. Thus, naturally abundant, non-bioactive β-caryophyllene can be easily converted into an antitermite reagent via a non-biological process.

  • 177.
    Ashkan, Fardost
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Skillinghaug, Bobo
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Fredrik, Svensson
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Prasad, Wakchaure
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Matyas, Wejdemar
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Mats, Larhed
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Christian, Sköld
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Experimental and Theoretical Investigation of Palladium(II)-Catalyzed Decarboxylative Synthesis of Electron-Rich Styrenes and 1,1-DiarylethenesManuskript (preprint) (Annet vitenskapelig)
  • 178. Ashour, Radwa M.
    et al.
    Abdel-Magied, Ahmed F.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Nuclear Materials Authority, Egypt.
    Abdel-Khalek, Ahmed A.
    Helaly, O. S.
    Ali, M. M.
    Preparation and characterization of magnetic iron oxide nanoparticles functionalized by L-cysteine: Adsorption and desorption behavior for rare earth metal ions2016Inngår i: Journal of Environmental Chemical Engineering, ISSN 2160-6544, E-ISSN 2213-3437, Vol. 4, nr 3, s. 3114-3121Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work, magnetic iron oxide nanoparticles functionalized with L-cysteine (Cys-Fe3O4 NPs) was synthesized and fully characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infra-red (FTIR), thermogravimetric analysis (TGA) and zeta potential measurements. The synthesized Cys-Fe(3)O(4)NPs has been evaluated as a highly adsorbent for the adsorption of a mixture of four rare earths RE3+ ions (La3+, Nd3+, Gd3+ and Y3+) from digested monazite solutions. The influence of various factors on the adsorption efficiency such as, the contact time, sample pH, temperature, and concentration of the stripping solution were investigated. The results indicate that Cys-Fe3O4 NPs achieve high removal efficiency 96.7, 99.3, 96.5 and 87% for La3+, Nd3+, Gd3+ and Y3+ ions, respectively, at pH = 6 within 15 min, and the adsorbent affinity for metal ions was found to be in order of Nd3+ > La3+ > Gd3+ > Y3+ ions. Using the Langmuir model, a maximum adsorption capacity of La3+, Nd3+, Gd3+ and Y3+ at room temperature was found to be 71.5, 145.5, 64.5 and 13.6 mg g (1), respectively. The Langmuir isotherm and pseudo-second order model fitted much better than the other isotherms and kinetic models. The obtained results for the thermodynamic parameters confirmed the spontaneous and endothermic nature of the process. Moreover, the desorption was carried out with 0.1 M nitric acid solutions. In addition, Cys-Fe3O4 NPs can be used as a highly efficient adsorbent for the adsorption of La3+, Nd3+, Gd3+ and Y3+ ions from digested monazite solutions.

  • 179.
    Athley, Karin
    et al.
    RISE, Innventia.
    Granlöf, Lars
    RISE, Innventia.
    Söderberg, Daniel
    RISE, Innventia.
    Ström, Göran
    RISE, Innventia.
    Optimizing the benefit of retention chemicals2014Konferansepaper (Fagfellevurdert)
  • 180. Atilaw, Yoseph
    et al.
    Duffy, Sandra
    Heydenreich, Matthias
    Muiva-Mutisya, Lois
    Avery, Vicky M
    Erdelyi, Mate
    Yenesew, Abiy
    Three Chalconoids and a Pterocarpene from the Roots of Tephrosia aequilata.2017Inngår i: Molecules, ISSN 1420-3049, E-ISSN 1420-3049, Vol. 22, nr 2, artikkel-id E318Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In our search for new antiplasmodial agents, the CH₂Cl₂/CH₃OH (1:1) extract of the roots of Tephrosia aequilata was investigated, and observed to cause 100% mortality of the chloroquine-sensitive (3D7) strain of Plasmodium falciparum at a 10 mg/mL concentration. From this extract three new chalconoids, E-2',6'-dimethoxy-3',4'-(2'',2''-dimethyl)pyranoretrochalcone (1, aequichalcone A), Z-2',6'-dimethoxy-3',4'-(2'',2''-dimethyl)pyranoretrochalcone (2, aequichalcone B), 4''-ethoxy-3''-hydroxypraecansone B (3, aequichalcone C) and a new pterocarpene, 3,4:8,9-dimethylenedioxy-6a,11a-pterocarpene (4), along with seven known compounds were isolated. The purified compounds were characterized by NMR spectroscopic and mass spectrometric analyses. Compound 1 slowly converts into 2 in solution, and thus the latter may have been enriched, or formed, during the extraction and separation process. The isomeric compounds 1 and 2 were both observed in the crude extract. Some of the isolated constituents showed good to moderate antiplasmodial activity against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum.

  • 181. Atilaw, Yoseph
    et al.
    Muiva-Mutisya, Lois
    Ndakala, Albert
    Akala, Hoseah M
    Yeda, Redemptah
    Wu, Yu J
    Coghi, Paolo
    Wong, Vincent K W
    Erdelyi, Mate
    Yenesew, Abiy
    Four Prenylflavone Derivatives with Antiplasmodial Activities from the Stem of Tephrosia purpurea subsp. leptostachya.2017Inngår i: Molecules, ISSN 1420-3049, E-ISSN 1420-3049, Vol. 22, nr 9, artikkel-id E1514Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Four new flavones with modified prenyl groups, namely (E)-5-hydroxytephrostachin (1), purleptone (2), (E)-5-hydroxyanhydrotephrostachin (3), and terpurlepflavone (4), along with seven known compounds (5-11), were isolated from the CH₂Cl₂/MeOH (1:1) extract of the stem of Tephrosia purpurea subsp. leptostachya, a widely used medicinal plant. Their structures were elucidated on the basis of NMR spectroscopic and mass spectrometric evidence. Some of the isolated compounds showed antiplasmodial activity against the chloroquine-sensitive D6 strains of Plasmodium falciparum, with (E)-5-hydroxytephrostachin (1) being the most active, IC50 1.7 ± 0.1 μM, with relatively low cytotoxicity, IC50 > 21 μM, against four cell-lines.

  • 182.
    Aune, Marie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Danielsson, Rolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Hussenius, Anita
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Ryberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Kristjansdottir, AG
    Uppsala universitet.
    Matsson, Olle
    Uppsala universitet.
    1,3-hydron transfer in some 5- or 7-substituted 1-methylindenes. Reaction rates and kinetic isotope effects1998Inngår i: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. 52, nr 7, s. 911-920s. 911-920Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rate constants and primary deuterium kinetic isotope effects (KIEs) have been determined for the base-catalysed 1,3-hydrotropic rearrangements of 1-methyl-5-nitroindene (12), 1-methyl-7-nitroindene (13), 5-methoxy-1-methylindene (14) and 5-fluoro-1-methy

  • 183.
    Aune, Marie
    et al.
    Uppsala universitet.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Kemiska institutionen.
    Matsson, Olle
    Uppsala universitet.
    Solvent Dependence of Enantioselectivity for a Base Catalyzed 1,3-Hydron Transfer Reaction: A Kinetic Isotope Effect and NMR Spectroscopic Study.1995Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 60, nr 5, s. 1356-1364s. 1356-1364Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The base-catalyzed rearrangement of 1-methylindene (1) to 3-methylindene (2) has been studied. The reaction proceeds with substrate enantioselectivity (kinetic resolution) when chiral tertiary amines are used as catalysts. When dihydroquinidine (DHQD) (3

  • 184.
    Axelsson, Karolin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Chemical signals in interactions between Hylobius abietis and associated bacteria2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The pine weevil (Hylobius abietis L.) is one of the two topmost economically important insect pests in Swedish conifer forests. The damage increase in areas were the silvicultural practice is to use clear cuttings were the insects gather and breed. During egglaying the female protects her offspring by creating a cave in roots and stumps were she puts her egg and covers it with frass, a mixture of weevil feces and chewed bark. Adult pine weevils have been observed to feed on the other side of the egg laying site and antifeedant substance has been discovered in the feces of the pine weevil. We think it is possible that microorganisms present in the frass contribute with antifeedant/repellent substances. Little is known about the pine weevils associated bacteria community and their symbiotic functions. In this thesis the bacterial community is characterized in gut and frass both from pine weevils in different populations across Europe as well as after a 28 day long diet regime on Scots pine, silver birch or bilberry. Volatile substances produced by isolated bacteria as well as from a consortium of microorganisms were collected with solid phase micro extraction (SPME) and analyzed with GC-MS. The main volatiles were tested against pine weevils using a two-choice test. Wolbachia, Rahnella aquatilis, Serratia and Pseudomonas syringae was commonly associated with the pine weevil. 2-Methoxyphenol, 2-phenylethanol, 3-methyl-1-butanol were found in the headspace from Rahnella aquatilis when grown in substrate containing pine bark. 2-Methoxyphenol and 3-methyl-1-butanol, phenol and methyl salicylate were found in pine feces. Birch and bilberry feces emitted mainly linalool oxides and bilberry emitted also small amounts of 2-phenylethanol.

    A second part of the thesis discusses the role of fungi in forest insect interactions and the production of oxygenated monoterpenes as possible antifeedants. Spruce bark beetles (Ips typhographus L.) aggregate with the help of pheromones and with collected forces they kill weakened adult trees as a result of associated fungi growth and larval development. A fungi associated with the bark beetle, Grosmannia europhoides, was shown to produce de novo 2-methyl-3-buten-2-ol, the major component of the spruce bark beetle aggregation pheromone. Chemical defense responses against Endoconidiophora polonica and Heterobasidion parviporum were investigated using four clones of Norway spruce with different susceptibility to Heterobasidion sp. Clone specific differences were found in induced mono-, sesqui and diterpenes. A number of oxygenated monoterpenes which are known antifeedants for the pine weevil were produced in the infested areas.

  • 185.
    Axelsson, Karolin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Konstanzer, Vera
    Kuttuva Rajarao, Guna
    KTH, Skolan för bioteknologi (BIO), Industriell bioteknologi.
    Terenius, Olle
    Dep of Ecology, SLU.
    Seriot, Lisa
    Nordenhem, Henrik
    Dep. of Ecology, SLU.
    Nordlander, Göran
    Dep. of Ecology, SLU.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Antifeedants produced by bacteria associated to the gut of the pine weevil (Hylobius abietis)Manuskript (preprint) (Annet vitenskapelig)
  • 186.
    Axelsson, Karolin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Nilsson, Louise
    Nordlander, Göran
    Dep. of Ecology, SLU.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Terenius, Olle
    Dep of Ecology, SLU.
    Do pine weevil microbiota and corresponding volatiles change due to selective feeding?Manuskript (preprint) (Annet vitenskapelig)
  • 187.
    Axelsson, Karolin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zendegi-Shiraz, Amene
    Swedjemark, Gunilla
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhao, Tao
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Clone specific chemical defense responses in Norway spruce to infestations by two pathogenic fungi2016Inngår i: Forest Pathology, ISSN 1437-4781, E-ISSN 1439-0329Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Heterobasidion parviporum (Hp) were investigated using four clones of Norway spruce (Picea abies) with different susceptibility to Heterobasidion sp. Eight year old trees were inoculated with Ep and Hp to minimize the variation due to environment. After three weeks the bark tissue at the upper border of the inoculation hole were extracted with hexane and analyzed by GC-MS. Both treatment and clonal differences were found based on induced mono-, sesqui- and diterpenes. In addition, the Hp produced toxin, fomanoxin, was identified in lowest amount in the most Hp susceptible clone. The clonal trees seem to use different defense strategies towards the two fungi. One of the clones was able to induce strong chemical defense against both fungi, one clone induced chemical defense only against Ep and the most susceptible clone exhibited the least capacity to produce an effective defense against Ep and Hp. Two diterpenes were found to be distinctly different between clones with different susceptibilities, which can be used as chemical indication of Norway spruce resistance against fungi.

  • 188.
    Axelsson, Linda
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Development of HIV-1 Protease Inhibitors and Palladium-Catalyzed Synthesis of Aryl Ketones and N-Allylbenzamides2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The use of palladium-catalyzed reactions to introduce new carbon-carbon bonds is a fundamental synthetic strategy that has been widely embraced due to its high chemo- and regioselectivity and functional group tolerance. In this context, Pd(0)-catalyzed aminocarbonylations using Mo(CO)6 instead of toxic and gaseous CO and with allylamine as the nucleophile were investigated. The aminocarbonylated product dominated over the Mizoroki-Heck product, and (hetero)aryl iodides, bromides and chlorides gave N-allylbenzamides in good yields.

    In this thesis improvements to an existing protocol for the Pd(II)-catalyzed synthesis of aryl ketones from five benzoic acids and a variety of nitriles are also presented. Addition of TFA improved the yields and employing THF as solvent enabled the use of solid nitriles, and the aryl ketones were isolated in good yields.

    The pandemic of HIV infection is one of the greatest public health issues of our time and approximately 35.3 million people worldwide are living with HIV. There are currently many drugs on the market targeting various parts of the viral reproduction cycle, but the problems of resistance warrant the search for new drugs. HIV-1 protease makes the virus mature into infectious particles. In this thesis a new type of HIV-1 protease inhibitor (PI) is presented, based on two of the PIs on the market, atazanavir and indinavir, but it has a tertiary alcohol, as well as a two-carbon tether between the quaternary carbon and the hydrazide β-nitrogen. A total of 25 new inhibitors were designed, synthesized and biologically evaluated, the best compound had an EC50 value of 3 nM.

    Based on this series a project aimed at synthesizing macrocycles spanning the P1-P3 area was initiated. Macrocycles often tend to have an improved affinity and metabolic profile compared to their linear analogs. Introduction of a handle in the para position of the P1 benzyl group proved difficult, despite efforts to synthesize intermediates containing either a bromo-, hydroxy-, methoxy-, silyl-group protected hydroxy- or an alkyne-group. The lactone intermediate was abandoned in favor of an alternative synthetic route and initial studies were found to be promising. This new approach requires further investigation before the target macrocycles can be synthesized. 

  • 189.
    Axelsson, Linda
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Veron, Jean-Baptiste
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Sävmarker, Jonas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Lindh, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Odell, Luke
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Larhed, Mats
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    An Improved Palladium(II)-Catalyzed Method for the Synthesis of Aryl Ketones from Aryl Carboxylic Acids and Organonitriles2014Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 55, nr 15, s. 2376-2380Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A palladium(II)-catalyzed decarboxylative protocol for the synthesis of aryl ketones has been developed. The addition of TFA was shown to improve the reaction yield and employing THF as solvent enabled the use of solid nitriles and in only a small excess. Using this method, five different benzoic acids reacted with a wide range of nitriles to produce 29 diverse (hetero)aryl ketone derivatives in up to 94% yield.

  • 190.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Larsson, Johanna M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Selander, Nicklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pincer complex-catalyzed redox coupling of alkenes with iodonium salts via presumed palladium(IV) intermediates2009Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 11, nr 13, s. 2852-2854Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Palladium pincer complexes directly catalyze the redox coupling reactions of functionalized alkenes and iodonium salts. The catalytic process, which is suitable for mild catalytic functionalization of allylic acetates and electron-rich alkenes, probably occurs through Pd(IV) intermediates. Due to the strong metal−ligand interactions, the oxidation of phosphine and amine ligands of the pincer complexes can be avoided in the presented reactions.

  • 191.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantioselective palladium pincer complex catalyzed carbon carbon coupling reactions between tosylimines and various nucleophiles2008Inngår i: Abstracts of Papers, 236th ACS National Meeting, Philadelphia, PA, United States, August 17-21, 2008, Washington, DC: American Chemical Society , 2008Konferansepaper (Annet vitenskapelig)
  • 192.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mechanistic considerations for the enantioselective palladium pincer complex catalyzed carbon-carbon coupling reactions2008Inngår i: Abstracts of Papers, 236th ACS National Meeting, Philadelphia, PA, United States, August 17-21, 2008, Washington, DC: American Chemical Society , 2008Konferansepaper (Annet vitenskapelig)
  • 193.
    Ayesa Alvarez, Susana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Design and Synthesis of Amine Building Blocks and Protease Inhibitors2008Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The first part of this thesis addresses the design and synthesis of amine building blocks accomplished by applying two different synthetic procedures, both of which were developed using solid-phase chemistry. Chapter 1 presents the first of these methods, entailing a practical solid-phase parallel synthesis route to N-monoalkylated aminopiperidines and aminopyrrolidines achieved by selective reductive alkylation of primary and/or secondary amines. Solid-phase NMR spectroscopy was used to monitor the reactions for which a new pulse sequence was developed. The second method, reported in Chapter 2, involves a novel approach to the synthesis of secondary amines starting from reactive alkyl halides and azides. The convenient solid-phase protocol that was devised made use of the Staudinger reaction in order to accomplish highly efficient alkylations of N-alkyl phosphimines or N-aryl phosphimines with reactive alkyl halides.

    The second part of the thesis describes the design and synthesis of three classes of protease inhibitors targeting the cysteine proteases cathepsins S and K, and the serine protease hepatitis C virus (HCV) NS3 protease. Chapter 4 covers the design, solid-phase synthesis, and structure-activity relationships of 4-amidofurane-3-one P1-containing inhibitors of cathepsin S and the effects of P3 sulfonamide groups on the potency and selectivity towards related cathepsin proteases. This work resulted in the discovery of highly potent and selective inhibitors of cathepsin S. Two parallel solid-phase approaches to the synthesis of a series of aminoethylamide inhibitors of cathepsin K are presented in Chapter 5. Finally, Chapter 6 reports peptide-based HCV NS3 protease inhibitors containing a non-electrophilic allylic alcohol moiety as P1 group and also outlines efforts to incorporate this new template into low-molecular-weight drug-like molecules.

  • 194.
    Ayesa, Susana
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Samuelsson, Bertil
    Classon, Björn
    A One-Pot, Solid-Phase Synthesis of Secondary Amines from Reactive Alkyl Halides and an Alkyl Azide2008Inngår i: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, nr 1, s. 77-79Artikkel i tidsskrift (Fagfellevurdert)
  • 195.
    Ayub, Rabia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström.
    Excited State Aromaticity and Antiaromaticity: Fundamental Studies and Applications2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The central theme of this thesis is the ability to tune various molecular properties by controlling and utilizing aromaticity and antiaromaticity in the lowest electronically excited states. This investigation is based on qualitative theory, quantum chemical (QC) calculations and experimental work.

    Baird's rule tells that the π-electron count for aromaticity and antiaromaticity is reversed in the ππ* triplet (T1) state when compared to Hückel's rule for the singlet ground state. The excited state aromatic character of [4n]annulenes is probed by usage of two structural moieties, the cyclopropyl (cPr) group and the silacyclobutene (SCB) ring. The results of QC calculations and photoreactivity experiments showed that the cPr group and the SCB ring remained closed when attached to or fused with [4n]annulenes so as to preserve T1 aromatic stabilization. In contrast, both moieties ring-opened when attached to or fused with [4n+2]annulenes as a means for alleviation of T1 antiaromaticity. These two structural moieties are shown to indicate T1 aromatic character of [4n]annulenes except in a limited number of cases.

    The T1 antiaromatic character of compounds with 4n+2 π-electrons was utilized for photo(hydro)silylations and photohydrogenations. QC calculations showed that due to T1 antiaromaticity, benzene is able to abstract hydrogen atoms from trialkylsilanes. The photoreactions occurred under mild conditions for benzene and certain polycyclic aromatic hydrocarbons. In contrast, COT was found to be unreactive under similar conditions.

    It is further revealed that various properties of molecules can be tailored by rational design using Baird’s rule. Three modes of connectivity (linear, bent, and cyclic) of polycyclic conjugated hydrocarbons (PCH) were explored by DFT calculations. When the PCHs contain a central [4n]unit and 4nπ-electron perimeter, bent isomers have lower triplet state energies than linear ones due to increased T1 aromaticity in the bent isomers. With regard to the cyclic connectivity, macrocyclic compounds are designed by modifying the C20 monocycle through incorporation of monocyclic units (all-carbon as well as heterocyclic) and the impact of macrocyclic T1 aromaticity upon insertion of different units is examined through QC calculations. The results provide insights on excited state aromaticity in macrocyclic systems.

  • 196.
    Ayub, Rabia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    El Bakouri, Ouissam
    Univ Girona, IQCC, C Maria Aurelia Capmany 6, Girona 17003, Catalonia, Spain..
    Jorner, Kjell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Sola, Miguel
    Univ Girona, IQCC, C Maria Aurelia Capmany 6, Girona 17003, Catalonia, Spain..
    Ottosson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Can Baird's and Clar's Rules Combined Explain Triplet State Energies of Polycyclic Conjugated Hydrocarbons with Fused 4n pi- and (4n+2)pi-Rings?2017Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 82, nr 12, s. 6327-6340Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Compounds that can be labeled as "aromatic chameleons" are pi-conjugated compounds that are able to adjust their pi-electron distributions so as to comply with the different rules of aromaticity in different electronic states. We used quantum chemical calculations to explore how the fusion of benzene rings onto aromatic chameleonic units represented by biphenylene, dibenbzocyclooctatetraene, and dibenzo[a,e]pentalene modifies the first triplet excited states (T-1) of the compounds. Decreases in T-1 energies are observed when going from isomers with linear connectivity of the fused benzene rings to those with cis- or transbent connectivities. The T-1 energies decreased down to those of the parent (isolated) 4n pi-electron units. Simultaneously, we observe an increased influence of triplet State aromaticity of the central 4n ring as given by Baird's rule and evidenced by geometric, magnetic, and electron density based aromaticity indices (HOMA, NICS-XY, ACID, and FLU). Because of an influence of,triplet state aromaticity in the central 4n pi-electron units,, the most stabilized, compounds, retain the triplet excitation in Baird pi-quartets or octets, enabling the outer benzene rings to adapt closed-shell singlet Clar pi-sextet character. Interestingly, the T-1 energies go down as the total number of aromatic cycles within a molecule in the T-1 state increases.

  • 197.
    Ayub, Rabia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. uppsala university.
    El Bakouri, Ouissam
    Univ Girona, IQCC, C Maria Aurelia Capmany 6, Girona 17003, Catalonia, Spain.
    Jorner, Kjell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. uppsala university.
    Sola, Miquel
    Univ Girona, IQCC, C Maria Aurelia Capmany 6, Girona 17003, Catalonia, Spain.
    Ottosson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. uppsala university.
    Can Baird’s and Clar’s Rules Combined Explain Triplet State Energies of Polycyclic Conjugated Hydrocarbons with Fused 4nπ- and (4n + 2)π-Rings?2017Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 82, nr 12, s. 6327-6340Artikkel i tidsskrift (Fagfellevurdert)
  • 198.
    Ayub, Rabia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    Jorner, Kjell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    Ottosson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    The silacyclobutene ring: An indicator of triplet state Baird-aromaticityManuskript (preprint) (Annet vitenskapelig)
  • 199.
    Ayub, Rabia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström.
    Ottosson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström.
    Relating the triplet state Baird-aromaticity of the monocycle to that of the macrocycleManuskript (preprint) (Annet vitenskapelig)
  • 200.
    Ayub, Rabia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Papadakis, Raffaello
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Jorner, Kjell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. uppsala university.
    Zietz, Burkhard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Ottosson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. uppsala university.
    Cyclopropyl Group: An Excited-State Aromaticity Indicator?2017Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, nr 55, s. 13684-13695Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The cyclopropyl (cPr) group, which is a well-known probe for detecting radical character at atoms to which it is connected, is tested as an indicator for aromaticity in the first * triplet and singlet excited states (T-1 and S-1). Baird's rule says that the -electron counts for aromaticity and antiaromaticity in the T-1 and S-1 states are opposite to Huckel's rule in the ground state (S-0). Our hypothesis is that the cPr group, as a result of Baird's rule, will remain closed when attached to an excited-state aromatic ring, enabling it to be used as an indicator to distinguish excited-state aromatic rings from excited-state antiaromatic and nonaromatic rings. Quantum chemical calculations and photoreactivity experiments support our hypothesis; calculated aromaticity indices reveal that openings of cPr substituents on [4n]annulenes ruin the excited-state aromaticity in energetically unfavorable processes. Yet, polycyclic compounds influenced by excited-state aromaticity (e.g., biphenylene), as well as 4n-electron heterocycles with two or more heteroatoms represent limitations.

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