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Kathiravan, S., Suriyanarayanan, S. & Nicholls, I. A. (2019). Electrooxidative Amination of sp2 C–H Bonds: Coupling of Amines with Aryl Amides via Copper Catalysis. Organic Letters, 21(7), 1968-1972
Open this publication in new window or tab >>Electrooxidative Amination of sp2 C–H Bonds: Coupling of Amines with Aryl Amides via Copper Catalysis
2019 (English)In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 21, no 7, p. 1968-1972Article in journal (Refereed) Published
Abstract [en]

Metal-catalyzed cross-coupling reactions are among the most important transformations in organic synthesis. However, the use of C−H activation for sp2 C−N bond formation remains one of the major challenges in the field of crosscoupling chemistry. Described herein is the first example of the synergistic combination of copper catalysis and electrocatalysis for aryl C−H amination under mild reaction conditions in an atom-and step-economical manner with the liberation of H2 as the sole and benign byproduct.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Organic Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-81882 (URN)10.1021/acs.orglett.9b00003 (DOI)
Available from: 2019-04-12 Created: 2019-04-12 Last updated: 2019-04-12Bibliographically approved
Mahajan, R., Rouhi, M., Shinde, S., Bedwell, T., Incel, A., Mavliutova, L., . . . Sellergren, B. (2019). Highly Efficient Synthesis and Assay of Protein-Imprinted Nanogels by Using Magnetic Templates. Angewandte Chemie International Edition, 58(3), 727-730
Open this publication in new window or tab >>Highly Efficient Synthesis and Assay of Protein-Imprinted Nanogels by Using Magnetic Templates
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2019 (English)In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 58, no 3, p. 727-730Article in journal (Refereed) Published
Abstract [en]

We report an approach integrating the synthesis of protein-imprinted nanogels ("plastic antibodies") with a highly sensitive assay employing templates attached to magnetic carriers. The enzymes trypsin and pepsin were immobilized on amino-functionalized solgel-coated magnetic nanoparticles (magNPs). Lightly crosslinked fluorescently doped polyacrylamide nanogels were subsequently produced by high-dilution polymerization of monomers in the presence of the magNPs. The nanogels were characterised by a novel competitive fluorescence assay employing identical protein-conjugated nanoparticles as ligands to reversibly immobilize the corresponding nanogels. Both nanogels exhibited K-d<10 pM for their respective target protein and low cross-reactivity with five reference proteins. This agrees with affinities reported for solid-phase-synthesized nanogels prepared using low-surface-area glass-bead supports. This approach simplifies the development and production of plastic antibodies and offers direct access to a practical bioassay.

Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2019
Keywords
competitive assays, molecularly imprinted polymers, nanogel synthesis, plastic antibodies
National Category
Organic Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-79846 (URN)10.1002/anie.201805772 (DOI)000455033700009 ()30308085 (PubMedID)
Funder
Knowledge Foundation, 20150086Knowledge Foundation, 20170059Swedish Research Council, 2014-4573
Note

Also funded by: Marie Sklodowska-Curie Actions (H2020-MSCA-ITN-2016)  -  722171-Biocapture

Available from: 2019-01-24 Created: 2019-01-24 Last updated: 2019-01-24Bibliographically approved
Giovannoli, C., Passini, C., Di Nardo, F., Anfossi, L., Baggiani, C. & Nicholls, I. A. (2018). Affinity Capillary Electrochromatography of Molecularly Imprinted Thin Layers Grafted onto Silica Capillaries Using a Surface-Bound Azo-Initiator and Living Polymerization. Polymers, 10(2), Article ID 192.
Open this publication in new window or tab >>Affinity Capillary Electrochromatography of Molecularly Imprinted Thin Layers Grafted onto Silica Capillaries Using a Surface-Bound Azo-Initiator and Living Polymerization
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2018 (English)In: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 10, no 2, article id 192Article in journal (Refereed) Published
Abstract [en]

Molecularly imprinted thin layers were prepared in silica capillaries by using two different surface polymerization strategies, the first using 4,4-azobis(4-cyanovaleric acid) as a surface-coupled radical initiator, and the second, S-carboxypropyl-S'-benzyltrithiocarbonate as a reversible addition-fragmentation chain transfer (RAFT) agent in combination with 2,2-azobisisobutyronitrile as a free radical initiator. The ability to generate imprinted thin layers was tested on two different polymerization systems: (i) a 4-vinylpyridine/ethylene dimethacrylate (4VP-EDMA) in methanol-water solution with 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) as a template; and (ii) methacrylic acid/ethylene dimethacrylate (MAA-EDMA) in a chloroform solution with warfarin as the template molecule. The binding properties of the imprinted capillaries were studied and compared with those of the corresponding non-imprinted polymer coated capillaries by injecting the template molecule and by measuring its migration times relative to a neutral and non-retained marker. The role of running buffer hydrophobicity on recognition was investigated by studying the influence of varying buffer acetonitrile concentration. The 2,4,5-T-imprinted capillary showed molecular recognition based on a reversed phase mechanism, with a decrease of the template recognition in the presence of higher acetonitrile content; whereas warfarin-imprinted capillaries showed a bell-shaped trend upon varying the acetonitrile percentage, illustrating different mechanisms underlying imprinted polymer-ligand recognition. Importantly, the results demonstrated the validity of affinity capillary electrochromatography (CEC) to screen the binding properties of imprinted layers.

Keywords
molecularly imprinted polymers, capillary electrophoresis, controlled/living radical polymerization, 2, 4, 5-trichlorophenoxyacedic acid, warfarin
National Category
Organic Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-72298 (URN)10.3390/polym10020192 (DOI)000427542900087 ()
Available from: 2018-04-10 Created: 2018-04-10 Last updated: 2018-11-16Bibliographically approved
Mandal, S., Suriyanarayanan, S., Nicholls, I. A. & Ramanujam, K. (2018). Electrochemically synthesized molecularly imprinted polyaniline nanostructure: A recognition matrix for biotinylated targets. Paper presented at 255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA. Abstract of Papers of the American Chemical Society, 255
Open this publication in new window or tab >>Electrochemically synthesized molecularly imprinted polyaniline nanostructure: A recognition matrix for biotinylated targets
2018 (English)In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2018
National Category
Chemical Sciences
Research subject
Natural Science, Chemistry
Identifiers
urn:nbn:se:lnu:diva-76897 (URN)000435537700366 ()
Conference
255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA
Available from: 2018-07-17 Created: 2018-07-17 Last updated: 2018-07-17Bibliographically approved
Ndizeye, N., Suriyanarayanan, S. & Nicholls, I. A. (2018). Hierarchical polymeric architectures through molecular imprinting in liquid crystalline environments. European Polymer Journal, 106, 223-231
Open this publication in new window or tab >>Hierarchical polymeric architectures through molecular imprinting in liquid crystalline environments
2018 (English)In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 106, p. 223-231Article in journal (Refereed) Published
Abstract [en]

The use of liquid crystalline (LC) media as sacrificial templates during the polymer synthesis has been explored. The LC-media introduce morphological features into resultant polymers which when used together with molecular imprinting can produce materials with hierarchical architectures. Bupivacaine (1) imprinted co-polymers of 2-hydroxyethylmethacrylate (HEMA) (2a) and 1,4-divinylbenzene (DVB) (3a) were synthesized using photochemical initiation in lyotrophic liquid crystalline phases of AOT (5) in water/p-xylene and Triton X-100 (6) /water systems. SEM studies revealed the impact of the LC-media on polymer morphology, with polymer brush-like structures, with bristles of ≈30 nm diameter. The polymer morphology reflects that of the hexagonal phase of the LC medium. The rebinding characteristics of polymer films were evaluated quartz crystal microbalance (QCM, under FIA conditions). The influence of the presence of imprinting-derived recognition sites in AOT (5) in water/p-xylene polymer film induced brush-like features which provided a 25-fold enhancement of sensor sensitivity. This chemosensor was shown to be selective for the local anesthetic template, bupivacaine, through studies using the structural analogues ropivacaine and mepivacaine.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
Bupivacaine, liquid crystalline medium, molecularly imprinted polymer, nanostructured polymer films, piezoelectric sensor, quartz crystal microbalance
National Category
Polymer Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-78287 (URN)10.1016/j.eurpolymj.2018.07.036 (DOI)000445993400027 ()
Available from: 2018-10-11 Created: 2018-10-11 Last updated: 2018-11-16Bibliographically approved
Mandal, S., Suriyanarayanan, S., Nicholls, I. A. & Ramanujam, K. (2018). Selective Sensing of the Biotinyl Moiety Using Molecularly Imprinted Polyaniline Nanowires. Journal of the Electrochemical Society, 165(14), B669-B678
Open this publication in new window or tab >>Selective Sensing of the Biotinyl Moiety Using Molecularly Imprinted Polyaniline Nanowires
2018 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 14, p. B669-B678Article in journal (Refereed) Published
Abstract [en]

A chemosensor for selective recognition of biotinyl moiety has been devised using electropolymerized film and tested against selective biotinylated targets. The sensor comprises biotin molecularly imprinted polymer (MIP) polymeric nanowires, as a recognition element, overlaid on gold-coated quartz transducers. The preparation of nanostructured MIPs and reference systems have been demonstrated using electrochemical copolymerization of the stabilized complex between the template (biotin), the functional monomer (4-aminobenzoic acid), and cross-linker (aniline) and/or sacrificial biotin-modified Al2O3 membrane. Density functional theoretical studies signify formation of a stable hydrogen-bonded complex of biotin with 4-aminobenzoic acid in the pre-polymerization mixture. Scanning electron microscope studies revealed uniformly grown and densely packed polyaniline hierarchical structures. Piezoelectric microgravimetry under flow injection analysis (FIA) conditions revealed selective binding of biotin methyl ester (BtOMe, 4) (79.89 +/- 2.17 Hz/mM) with imprinted polyaniline hierarchical structures over 10 fold higher than the non-imprinted counterpart. The detection limit of the MIP is 50 nM under optimized conditions. Particularly, the sensor selectively recognizes BtOMe from structural or functional analogues, such as thiamine (4.87 +/- 0.10 Hz/mM) and pyridoxamine (12.08 +/- 0.24 Hz/mM). Importantly, the MIP hierarchical structures were shown to be selective for biotinylated targets (biotin moiety labeled cytochrome C, dextran, oxytocin and obestatin). (C) 2018 The Electrochemical Society.

Place, publisher, year, edition, pages
Electrochemical Society, 2018
National Category
Biochemistry and Molecular Biology Biophysics
Research subject
Chemistry, Biochemistry
Identifiers
urn:nbn:se:lnu:diva-78608 (URN)10.1149/2.0401814jes (DOI)000447842800001 ()
Available from: 2018-11-02 Created: 2018-11-02 Last updated: 2018-11-02Bibliographically approved
Nicholls, I. A., Olsson, G. D., Karlsson, B. C. G., Suriyanarayanan, S. & Wiklander, J. G. (2018). Theoretical and Computational Strategies in Molecularly Imprinted Polymer Development. In: Wlodzimierz Kutner, Piyush Sindhu Sharma (Ed.), Molecularly Imprinted Polymers for Analytical Chemistry Applications: (pp. 197-226). London: Royal Society of Chemistry
Open this publication in new window or tab >>Theoretical and Computational Strategies in Molecularly Imprinted Polymer Development
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2018 (English)In: Molecularly Imprinted Polymers for Analytical Chemistry Applications / [ed] Wlodzimierz Kutner, Piyush Sindhu Sharma, London: Royal Society of Chemistry, 2018, p. 197-226Chapter in book (Refereed)
Abstract [en]

Theoretical and computational studies of molecular imprinting have helped provide valuable insights concerning the nature of the molecular-level events underlying the recognition characteristics of molecularly imprinted materials. Here, we first present an overview of a thermodynamic treatment of factors governing the behaviour of these functional materials, and then a summary of the development and current status of the use of computational strategies for studying aspects of molecular imprinting and the resulting material properties.

Place, publisher, year, edition, pages
London: Royal Society of Chemistry, 2018
Series
Polymer Chemistry Series
National Category
Theoretical Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-81879 (URN)10.1039/9781788010474-00197 (DOI)978-1-78262-647-3 (ISBN)978-1-78801-047-4 (ISBN)978-1-78801-427-4 (ISBN)
Available from: 2019-04-12 Created: 2019-04-12 Last updated: 2019-04-24Bibliographically approved
Kathiravan, S. & Nicholls, I. A. (2017). Cobalt Catalyzed, Regioselective C(sp(2))-H Activation of Amides with 1,3-Diynes. Organic Letters, 19(18), 4758-4761
Open this publication in new window or tab >>Cobalt Catalyzed, Regioselective C(sp(2))-H Activation of Amides with 1,3-Diynes
2017 (English)In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 19, no 18, p. 4758-4761Article in journal (Refereed) Published
Abstract [en]

The development of a first row transition metal (cobalt)-based catalyst for the as yet unexplored CH activation-driven reaction of 1,3-diynes, themselves a functional class of interest in a range of application areas, to form isoquinolinonesan important structural motif in a number of biologically active substancesis presented. This versatile and inexpensive catalyst employs a covalently attached bidendate-directing group, 8-aminoquinoline. The template directs the CH activation and facilitates the synthesis of a wide range of alkynylated heterocycles under mild conditions and with excellent regioselectivity. This strategy provides a novel and efficient route to diverse heterocyclic frameworks as demonstrated by its late stage application in bisheterocycle syntheses.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2017
National Category
Organic Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-68333 (URN)10.1021/acs.orglett.7b02119 (DOI)000411304300014 ()28846427 (PubMedID)
Available from: 2017-10-12 Created: 2017-10-12 Last updated: 2019-04-12Bibliographically approved
Suriyanarayanan, S., Mandal, S., Ramanujam, K. & Nicholls, I. A. (2017). Electrochemically synthesized molecularly imprinted polythiophene nanostructures as recognition elements for an aspirin-chemosensor. Sensors and actuators. B, Chemical, 253, 428-436
Open this publication in new window or tab >>Electrochemically synthesized molecularly imprinted polythiophene nanostructures as recognition elements for an aspirin-chemosensor
2017 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 253, p. 428-436Article in journal (Refereed) Published
Abstract [en]

A chemosensor utilizing electro-polymerized film, as recognition element, has been devised and tested for selective determination of aspirin. The sensor consists of molecularly imprinted polymer (MIP) recognition elements electrodeposited as polymeric nanowires on gold-coated quartz resonator. A nano structures were prepared by electrochemical co-polymerization of the preformed complex between the template, aspirin, the functional monomers, 3-thienylboronic acid (3-TBA) and 3-thiopheneacetic acid (3-TAA), and thiophene, which was employed as a cross-linker. This nanostructure upon leaching aspirin serve as MIP. Polymerizations were performed in acetonitrile (MIP-org) as well as a micelle forming medium (MIP-mic). For MIP nanowire (MIP-ano) synthesis, sacrificial alumina templates were used during electro-polymerization in acetonitrile. Scanning electron microscope studies revealed compactly arranged polythiophene nanowires of uniform thickness in MIP-ano film, and MIP-mic film produced aggregated micron sized polymer structures. Density functional theoretical studies indicated a stable hydrogen bond-based complexation of aspirin by 3-TBA and 3-TAA in the pre-polymerization mixture implying that the MIP film thus prepared could selectively rebind the aspirin template. The MIP-ano-based chemosensor was sensitive towards aspirin (0.5-10 mM), over clinically relevant range (0.15-0.5 mM) under optimized FIA conditions. The sensitivity (20.62 Hz/mM) of the MIP-ano was eight and fifteen times higher than the MIP-mic (2.80 Hz/mM) and MIP-org (1.10 Hz/mM). Notably, the sensor selectively discriminates aspirin from structurally or functionally related interferants and metabolites, such as, salicylic acid, acetylsalicyloyl chloride and ibuprofen. (C) 2017 Elsevier B.V. All rights reserved.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Electrochemical polymerization, Aspirin chemosensor, Quartz crystal microbalance, Sacrificial template
National Category
Organic Chemistry
Research subject
Chemistry, Organic Chemistry
Identifiers
urn:nbn:se:lnu:diva-68574 (URN)10.1016/j.snb.2017.05.076 (DOI)000411124800051 ()
Available from: 2017-11-02 Created: 2017-11-02 Last updated: 2018-11-16Bibliographically approved
Kathiravan, S. & Nicholls, I. A. (2017). Monoprotected L-Amino Acid (L-MPAA), Accelerated Bromination, Chlorination, and Iodination of C(sp(2))-H Bonds by Iridium(III) Catalysis. Chemistry - A European Journal, 23(29), 7031-7036
Open this publication in new window or tab >>Monoprotected L-Amino Acid (L-MPAA), Accelerated Bromination, Chlorination, and Iodination of C(sp(2))-H Bonds by Iridium(III) Catalysis
2017 (English)In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, no 29, p. 7031-7036Article in journal (Refereed) Published
Abstract [en]

Halogenated arenes are important structural motifs commonly found in biologically active molecules and used for a variety of transformations in organic synthesis. Herein, we report the mono-protected L-amino acid (L-MPAA) accelerated iridium(III)-catalyzed halogenation of (hetero)anilides at room temperature. This reaction constitutes the first example of an iridium(III)/L-MPAA-catalyzed general halogenation of (hetero)arenes through C(sp(2))-H activation. Furthermore, we demonstrate the potential utility of our method through its use in the synthesis of a quinolone derivative.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2017
Keywords
anilides, C-H activation, halogenation, iridium, L-MPAA
National Category
Chemical Sciences
Research subject
Natural Science, Chemistry
Identifiers
urn:nbn:se:lnu:diva-66986 (URN)10.1002/chem.201700280 (DOI)000401992100016 ()28221698 (PubMedID)
Available from: 2017-07-20 Created: 2017-07-20 Last updated: 2019-04-12Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-0407-6542

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