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  1. Article: A Formal Total Synthesis of (-)-Brevisamide.

    Smith, Amos B / Kutsumura, Noriki / Potuzak, Justin

    Tetrahedron letters

    2011  Volume 52, Issue 17, Page(s) 2117–2119

    Abstract: A formal total synthesis of (-)-brevisamide has been achieved. The synthetic approach highlights a chemoselective asymmetric dihydroxylation and a one-pot Fraser-Reid epoxidation/PMB protection reaction sequence. ...

    Abstract A formal total synthesis of (-)-brevisamide has been achieved. The synthetic approach highlights a chemoselective asymmetric dihydroxylation and a one-pot Fraser-Reid epoxidation/PMB protection reaction sequence.
    Language English
    Publishing date 2011-05-04
    Publishing country England
    Document type Journal Article
    ZDB-ID 204287-3
    ISSN 1873-3581 ; 0040-4039
    ISSN (online) 1873-3581
    ISSN 0040-4039
    DOI 10.1016/j.tetlet.2010.11.013
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: A formal total synthesis of (−)-brevisamide

    Smith, Amos B., III / Kutsumura, Noriki / Potuzak, Justin

    Tetrahedron letters. 2011 Apr. 27, v. 52, no. 17

    2011  

    Abstract: A formal total synthesis of (−)-brevisamide has been achieved. The synthetic approach highlights a chemoselective asymmetric dihydroxylation and a one-pot Fraser-Reid epoxidation/PMB protection reaction sequence. ...

    Abstract A formal total synthesis of (−)-brevisamide has been achieved. The synthetic approach highlights a chemoselective asymmetric dihydroxylation and a one-pot Fraser-Reid epoxidation/PMB protection reaction sequence.
    Keywords chemical structure ; dihydroxylation ; organic compounds
    Language English
    Dates of publication 2011-0427
    Size p. 2117-2119.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 204287-3
    ISSN 1873-3581 ; 0040-4039
    ISSN (online) 1873-3581
    ISSN 0040-4039
    DOI 10.1016/j.tetlet.2010.11.013
    Database NAL-Catalogue (AGRICOLA)

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  3. Article: Stereocontrolled synthesis of spiroketals via Ti(Oi-Pr)4-mediated kinetic spirocyclization of glycal epoxides with retention of configuration.

    Moilanen, Sirkka B / Potuzak, Justin S / Tan, Derek S

    Journal of the American Chemical Society

    2006  Volume 128, Issue 6, Page(s) 1792–1793

    Abstract: A Ti(Oi-Pr)4-mediated kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to most existing methods for spiroketal synthesis, this reaction does not rely upon ... ...

    Abstract A Ti(Oi-Pr)4-mediated kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to most existing methods for spiroketal synthesis, this reaction does not rely upon thermodynamic control over the stereochemical configuration at the anomeric carbon. Stereochemically diverse glycals are first alkylated at the C1-position to introduce a hydroxyl-bearing side chain, then epoxidized stereoselectively. Treatment with Ti(Oi-Pr)4 leads to an unusual kinetic epoxide-opening spirocyclization (spirocycloisomerization) with retention of configuration at the anomeric carbon. The reaction is proposed to proceed via a chelation-controlled mechanism and has been used to form five-, six-, and seven-membered rings with stereochemically diverse substituents. This approach may also be useful for the related intermolecular beta-mannosidation reaction. This Ti(Oi-Pr)4-mediated spirocyclization is stereochemically complementary to our previously reported MeOH-induced spirocyclization, which proceeds with inversion of configuration, and together, these reactions provide comprehensive access to systematically stereochemically diversified spiroketals.
    MeSH term(s) Carbohydrate Conformation ; Cyclization ; Epoxy Compounds/chemistry ; Glycosides/chemical synthesis ; Glycosides/chemistry ; Hexoses/chemistry ; Kinetics ; Spiro Compounds/chemical synthesis ; Spiro Compounds/chemistry ; Stereoisomerism ; Titanium/chemistry
    Chemical Substances Epoxy Compounds ; Glycosides ; Hexoses ; Spiro Compounds ; Titanium (D1JT611TNE)
    Language English
    Publishing date 2006-02-06
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/ja057908f
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Discovery and applications of small molecule probes for studying biological processes.

    Potuzak, Justin S / Moilanen, Sirkka B / Tan, Derek S

    Biotechnology & genetic engineering reviews

    2006  Volume 21, Page(s) 11–78

    MeSH term(s) Biological Assay/methods ; Biology/methods ; Cell Physiological Phenomena ; Drug Design ; Gene Expression Profiling/methods ; Gene Targeting/methods ; Molecular Biology/methods ; Molecular Probe Techniques ; Signal Transduction/physiology
    Language English
    Publishing date 2006-09-28
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 49457-4
    ISSN 0264-8725
    ISSN 0264-8725
    DOI 10.1080/02648725.2004.10648049
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Stereocontrolled synthesis of spiroketals via a remarkable methanol-induced kinetic spirocyclization reaction.

    Potuzak, Justin S / Moilanen, Sirkka B / Tan, Derek S

    Journal of the American Chemical Society

    2005  Volume 127, Issue 40, Page(s) 13796–13797

    Abstract: A methanol-induced kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to existing methods for spiroketal synthesis, this reaction does not depend on ... ...

    Abstract A methanol-induced kinetic spiroketalization reaction has been developed for the stereocontrolled target- and diversity-oriented synthesis of spiroketals. In contrast to existing methods for spiroketal synthesis, this reaction does not depend on thermodynamic product stability or require axial attack of an oxygen nucleophile. Stereodiverse glycals are alkylated at the C1 position with side chains bearing protected hydroxyl groups. After alcohol deprotection, the glycal is epoxidized stereoselectively, then the side chain hydroxyl is spirocyclized with inversion of configuration at the anomeric carbon by addition of excess MeOH at -63 degrees C. This spirocyclization reaction appears to proceed by MeOH hydrogen-bonding catalysis and has been used to form five- and six-membered rings with stereoisomeric substituents. In some cases, the stereocomplementary spiroketals can be also obtained by classical acid-catalyzed equilibration.
    MeSH term(s) Cyclization ; Kinetics ; Methanol/chemistry ; Molecular Conformation ; Spiro Compounds/chemical synthesis ; Spiro Compounds/chemistry ; Stereoisomerism
    Chemical Substances Spiro Compounds ; Methanol (Y4S76JWI15)
    Language English
    Publishing date 2005-10-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/ja055033z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Differential signaling properties at the kappa opioid receptor of 12-epi-salvinorin A and its analogues

    Béguin, Cécile / Potuzak, Justin / Xu, Wei / Liu-Chen, Lee-Yuan / Streicher, John M / Groer, Chad E / Bohn, Laura M / Carlezon, William A., Jr / Cohen, Bruce M

    Bioorganic & medicinal chemistry letters. 2012 Jan. 15, v. 22, no. 2

    2012  

    Abstract: The kappa opioid receptor (KOPR) has been identified as a potential drug target to prevent or alter the course of mood, anxiety and addictive disorders or reduce response to stress. In a search for highly potent and selective KOPR partial agonists as ... ...

    Abstract The kappa opioid receptor (KOPR) has been identified as a potential drug target to prevent or alter the course of mood, anxiety and addictive disorders or reduce response to stress. In a search for highly potent and selective KOPR partial agonists as pharmacological tools, we have modified 12-epi-salvinorin A, a compound which we have previously observed to be a KOPR partial agonist. Five analogues of 12-epi-salvinorin A were synthesized and their effects on G protein activation as well as β-arrestin2 recruitment were evaluated. Only 12-epi-salvinorin A (1) partially activated signaling through G proteins, yet acted as a full agonist in the β-arrestin 2 DiscoveRx assay. Other salvinorin analogues tested in these functional assays were full agonists in both assays of KOPR activation. By comparison, the non-selective opioid ligand nalbuphine, known to be a partial agonist for G-protein activation, was also a partial agonist for the β-arrestin mediated signaling pathway activated through KOPR.
    Keywords proteins ; drugs ; stress response ; signal transduction ; agonists ; anxiety
    Language English
    Dates of publication 2012-0115
    Size p. 1023-1026.
    Publishing place Elsevier Ltd
    Document type Article
    Note 2019-12-06
    ZDB-ID 1063195-1
    ISSN 1464-3405 ; 0960-894X
    ISSN (online) 1464-3405
    ISSN 0960-894X
    DOI 10.1016/j.bmcl.2011.11.128
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: The microtubule-stabilizing agent, epothilone D, reduces axonal dysfunction, neurotoxicity, cognitive deficits, and Alzheimer-like pathology in an interventional study with aged tau transgenic mice.

    Zhang, Bin / Carroll, Jenna / Trojanowski, John Q / Yao, Yuemang / Iba, Michiyo / Potuzak, Justin S / Hogan, Anne-Marie L / Xie, Sharon X / Ballatore, Carlo / Smith, Amos B / Lee, Virginia M-Y / Brunden, Kurt R

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2012  Volume 32, Issue 11, Page(s) 3601–3611

    Abstract: Neurodegenerative tauopathies, such as Alzheimer's disease (AD), are characterized by insoluble deposits of hyperphosphorylated tau protein within brain neurons. Increased phosphorylation and decreased solubility has been proposed to diminish normal tau ... ...

    Abstract Neurodegenerative tauopathies, such as Alzheimer's disease (AD), are characterized by insoluble deposits of hyperphosphorylated tau protein within brain neurons. Increased phosphorylation and decreased solubility has been proposed to diminish normal tau stabilization of microtubules (MTs), thereby leading to neuronal dysfunction. Earlier studies have provided evidence that small molecule MT-stabilizing drugs that are used in the treatment of cancer may have utility in the treatment of tauopathies. However, it has not been established whether treatment with a small molecule MT-stabilizing compound will provide benefit in a transgenic model with pre-existing tau pathology, as would be seen in human patients with clinical symptoms. Accordingly, we describe here an interventional study of the brain-penetrant MT-stabilizing agent, epothilone D (EpoD), in aged PS19 mice with existing tau pathology and related behavioral deficits. EpoD treatment reduced axonal dystrophy and increased axonal MT density in the aged PS19 mice, which led to improved fast axonal transport and cognitive performance. Moreover, the EpoD-treated PS19 mice had less forebrain tau pathology and increased hippocampal neuronal integrity, with no dose-limiting side effects. These data reveal that brain-penetrant MT-stabilizing drugs hold promise for the treatment of AD and related tauopathies, and that EpoD could be a candidate for clinical testing.
    MeSH term(s) Aging/drug effects ; Aging/pathology ; Aging/psychology ; Alzheimer Disease/drug therapy ; Alzheimer Disease/pathology ; Alzheimer Disease/psychology ; Animals ; Axons/drug effects ; Axons/pathology ; Cognition Disorders/drug therapy ; Cognition Disorders/pathology ; Cognition Disorders/psychology ; Epothilones/pharmacology ; Epothilones/therapeutic use ; Humans ; Male ; Mice ; Mice, Transgenic ; Microtubules/drug effects ; Microtubules/pathology ; Neurotoxicity Syndromes/drug therapy ; Neurotoxicity Syndromes/pathology ; Neurotoxicity Syndromes/psychology ; Tauopathies/drug therapy ; Tauopathies/pathology ; Tauopathies/psychology ; Tubulin Modulators/pharmacology ; Tubulin Modulators/therapeutic use ; tau Proteins/genetics
    Chemical Substances Epothilones ; Tubulin Modulators ; tau Proteins ; desoxyepothilone B (T0358E0YUF)
    Language English
    Publishing date 2012-03-15
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.4922-11.2012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Differential signaling properties at the kappa opioid receptor of 12-epi-salvinorin A and its analogues.

    Béguin, Cécile / Potuzak, Justin / Xu, Wei / Liu-Chen, Lee-Yuan / Streicher, John M / Groer, Chad E / Bohn, Laura M / Carlezon, William A / Cohen, Bruce M

    Bioorganic & medicinal chemistry letters

    2011  Volume 22, Issue 2, Page(s) 1023–1026

    Abstract: The kappa opioid receptor (KOPR) has been identified as a potential drug target to prevent or alter the course of mood, anxiety and addictive disorders or reduce response to stress. In a search for highly potent and selective KOPR partial agonists as ... ...

    Abstract The kappa opioid receptor (KOPR) has been identified as a potential drug target to prevent or alter the course of mood, anxiety and addictive disorders or reduce response to stress. In a search for highly potent and selective KOPR partial agonists as pharmacological tools, we have modified 12-epi-salvinorin A, a compound which we have previously observed to be a KOPR partial agonist. Five analogues of 12-epi-salvinorin A were synthesized and their effects on G protein activation as well as β-arrestin2 recruitment were evaluated. Only 12-epi-salvinorin A (1) partially activated signaling through G proteins, yet acted as a full agonist in the β-arrestin 2 DiscoveRx assay. Other salvinorin analogues tested in these functional assays were full agonists in both assays of KOPR activation. By comparison, the non-selective opioid ligand nalbuphine, known to be a partial agonist for G-protein activation, was also a partial agonist for the β-arrestin mediated signaling pathway activated through KOPR.
    MeSH term(s) Cell Line, Tumor ; Diterpenes, Clerodane/chemical synthesis ; Diterpenes, Clerodane/chemistry ; Diterpenes, Clerodane/pharmacology ; Dose-Response Relationship, Drug ; Humans ; Molecular Conformation ; Receptors, Opioid, kappa/agonists ; Receptors, Opioid, kappa/metabolism ; Signal Transduction/drug effects ; Structure-Activity Relationship
    Chemical Substances Diterpenes, Clerodane ; Receptors, Opioid, kappa ; salvinorin A (T56W91NG6J)
    Language English
    Publishing date 2011-12-07
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1063195-1
    ISSN 1464-3405 ; 0960-894X
    ISSN (online) 1464-3405
    ISSN 0960-894X
    DOI 10.1016/j.bmcl.2011.11.128
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: The characterization of microtubule-stabilizing drugs as possible therapeutic agents for Alzheimer's disease and related tauopathies

    Brunden, Kurt R / Yao, Yuemang / Potuzak, Justin S / Ferrer, Nuria Ibarz / Ballatore, Carlo / James, Michael J / Hogan, Anne-Marie L / Trojanowski, John Q / Smith, Amos B., III / Lee, Virginia M.-Y

    Pharmacological research. 2011 Apr., v. 63, no. 4

    2011  

    Abstract: Tau, a protein that is enriched in neurons of the central nervous system (CNS), is thought to play a critical role in the stabilization of microtubules (MTs). Several neurodegenerative disorders referred to as tauopathies, including Alzheimer's disease ... ...

    Abstract Tau, a protein that is enriched in neurons of the central nervous system (CNS), is thought to play a critical role in the stabilization of microtubules (MTs). Several neurodegenerative disorders referred to as tauopathies, including Alzheimer's disease and certain types of frontotemporal lobar degeneration, are characterized by the intracellular accumulation of hyperphosphorylated tau fibrils. Tau deposition into insoluble aggregates is believed to result in a loss of tau function that leads to MT destabilization, and this could cause neurodegeneration as intact MTs are required for axonal transport and normal neuron function. This tau loss-of-function hypothesis has been validated in a tau transgenic mouse model with spinal cord tau inclusions, where the MT-stabilizing agent, paclitaxel, increased spinal nerve MT density and improved motor function after drug absorption at neuromuscular junctions. Unfortunately, paclitaxel is a P-glycoprotein substrate and has poor blood–brain barrier permeability, making it unsuitable for the treatment of human tauopathies. We therefore examined several MT-stabilizing compounds from the taxane and epothilone natural product families to assess their membrane permeability and to determine whether they act as substrates or inhibitors of P-glycoprotein. Moreover, we compared brain and plasma levels of the compounds after administration to mice. Finally, we assessed whether brain-penetrant compounds could stabilize mouse CNS MTs. We found that several epothilones have significantly greater brain penetration than the taxanes. Furthermore, certain epothilones cause an increase in CNS MT stabilization, with epothilone D demonstrating a favorable pharmacokinetic and pharmacodynamic profile which suggests this agent merits further study as a potential tauopathy drug candidate.
    Keywords Alzheimer disease ; animal models ; blood-brain barrier ; brain ; cytoplasmic streaming ; drugs ; genetically modified organisms ; humans ; membrane permeability ; mice ; microtubules ; nerve tissue ; neurodegenerative diseases ; neurons ; paclitaxel ; pharmacokinetics ; spinal cord ; taxanes
    Language English
    Dates of publication 2011-04
    Size p. 341-351.
    Publishing place Elsevier Ltd
    Document type Article
    ISSN 1043-6618
    DOI 10.1016/j.phrs.2010.12.002
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  10. Article ; Online: Epothilone D improves microtubule density, axonal integrity, and cognition in a transgenic mouse model of tauopathy.

    Brunden, Kurt R / Zhang, Bin / Carroll, Jenna / Yao, Yuemang / Potuzak, Justin S / Hogan, Anne-Marie L / Iba, Michiyo / James, Michael J / Xie, Sharon X / Ballatore, Carlo / Smith, Amos B / Lee, Virginia M-Y / Trojanowski, John Q

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2010  Volume 30, Issue 41, Page(s) 13861–13866

    Abstract: Neurons in the brains of those with Alzheimer's disease (AD) and many frontotemporal dementias (FTDs) contain neurofibrillary tangles comprised of hyperphosphorylated tau protein. Tau normally stabilizes microtubules (MTs), and tau misfolding could lead ... ...

    Abstract Neurons in the brains of those with Alzheimer's disease (AD) and many frontotemporal dementias (FTDs) contain neurofibrillary tangles comprised of hyperphosphorylated tau protein. Tau normally stabilizes microtubules (MTs), and tau misfolding could lead to a loss of this function with consequent MT destabilization and neuronal dysfunction. Accordingly, a possible therapeutic strategy for AD and related "tauopathies" is treatment with a MT-stabilizing anti-cancer drug such as paclitaxel. However, paclitaxel and related taxanes have poor blood-brain barrier permeability and thus are unsuitable for diseases of the brain. We demonstrate here that the MT-stabilizing agent, epothilone D (EpoD), is brain-penetrant and we subsequently evaluated whether EpoD can compensate for tau loss-of-function in PS19 tau transgenic mice that develop forebrain tau inclusions, axonal degeneration and MT deficits. Treatment of 3-month-old male PS19 mice with low doses of EpoD once weekly for a 3 month period significantly improved CNS MT density and axonal integrity without inducing notable side-effects. Moreover, EpoD treatment reduced cognitive deficits that were observed in the PS19 mice. These results suggest that certain brain-penetrant MT-stabilizing agents might provide a viable therapeutic strategy for the treatment of AD and FTDs.
    MeSH term(s) Animals ; Axons/drug effects ; Axons/metabolism ; Axons/pathology ; Brain/drug effects ; Brain/metabolism ; Brain/pathology ; Brain/physiopathology ; Cognition/drug effects ; Epothilones/pharmacology ; Epothilones/therapeutic use ; Female ; Male ; Maze Learning/drug effects ; Mice ; Mice, Transgenic ; Microscopy, Electron ; Microtubules/drug effects ; Microtubules/metabolism ; Microtubules/pathology ; Motor Skills/drug effects ; Neurons/drug effects ; Neurons/metabolism ; Neurons/pathology ; Phosphorylation ; Random Allocation ; Rotarod Performance Test ; Tauopathies/drug therapy ; Tauopathies/metabolism ; Tauopathies/pathology ; Tauopathies/physiopathology ; Tubulin Modulators/pharmacology ; Tubulin Modulators/therapeutic use ; tau Proteins/metabolism
    Chemical Substances Epothilones ; Tubulin Modulators ; tau Proteins ; desoxyepothilone B (T0358E0YUF)
    Language English
    Publishing date 2010-10-13
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.3059-10.2010
    Database MEDical Literature Analysis and Retrieval System OnLINE

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