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Witty M, Dingra NN, Abboud KA, Felts AC, Ayudhya TIN. Nuclear Magnetic Resonance and X-ray Crystallography to Improve Struvite Determination. ANAL LETT 2017. [DOI: 10.1080/00032719.2017.1302459] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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77
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Quadri M, Stokes C, Gulsevin A, Felts ACJ, Abboud KA, Papke RL, Horenstein NA. Sulfonium as a Surrogate for Ammonium: A New α7 Nicotinic Acetylcholine Receptor Partial Agonist with Desensitizing Activity. J Med Chem 2017; 60:7928-7934. [PMID: 28885019 DOI: 10.1021/acs.jmedchem.7b00875] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Weak partial agonists that promote a desensitized state of the α7 nicotinic acetylcholine receptor (nAChR) have been associated with anti-inflammatory effects. Exemplar compounds feature a tertiary or quaternary ammonium group. We report the synthesis, structure, and electrophysiological evaluation of 1-ethyl-4-phenylthiomorpholin-1-ium triflate, a weak partial agonist with a sulfonium isostere of the ammonium pharmacophore. These results offer new insights in understanding nAChR-ligand interactions and provide a new chemical space to target the α7 nAChR.
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Fournet AD, Mitchell KJ, Wernsdorfer W, Abboud KA, Christou G. Three-Dimensional (3-D) Ferromagnetic Network of Mn 12 Single-Molecule Magnets: Subtle Environmental Effects and Switching to Antiferromagnetic. Inorg Chem 2017; 56:10706-10716. [PMID: 28829615 DOI: 10.1021/acs.inorgchem.7b01676] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new member of the Mn12 family of single-molecule magnets (SMMs) has been prepared and found to be the first of this family to give a 3-D ferromagnetic network. [Mn12O12(O2CC6H4-p-F)16(H2O)4] (2) was prepared by carboxylate substitution on the acetate derivative with p-F-benzoic acid and crystallizes as 2·8MeCN in space group I4̅2m with extensive formation of intermolecular C-H···F hydrogen-bonding. The latter leads to a combination of ferromagnetic (F) and antiferromagnetic (AF) interactions and an overall F network that gives a χMT value at low T that is abnormally high for an S = 10 ground state. 2·8MeCN undergoes solvent loss under vacuum to 2, with a decrease in unit-cell volume of 17%, primarily due to a 13% decrease in the c-axis. The χMT vs T plot for 2 indicates a switch to a net AF network. Exposure to air causes hydration to 2·3H2O, a concomitant increase in unit cell volume, and a switch back to a F network. The same conversion of 2·8MeCN to 2·3H2O can also be accomplished in one step rather than two steps, by leaving crystals of the former exposed to air at ambient temperature and pressure for 10 days, giving the same magnetic plots. Interestingly, the desolvation/solvation processes cause Jahn-Teller isomerism to occur, but the ratio of the faster-relaxing isomer to the normal slowly relaxing one does not change monotonically. Single-crystal micro-SQUID studies on 2·8MeCN show the expected magnetization hysteresis loops for a SMM and a small exchange-bias from the intermolecular interactions that is unexpectedly AF. Since the micro-SQUID study only identifies interactions along the easy-axis (z-axis) of the crystal, this is readily rationalized as due to the Jz components of the intermolecular interactions in 2·8MeCN being net AF. The combined results offer useful insights into the degree of sensitivity of the magnetic properties to small environmental perturbations.
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79
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Adebayo OA, Abboud KA, Christou G. Mn3 Single-Molecule Magnets and Mn6/Mn9 Clusters from the Use of Methyl 2-Pyridyl Ketone Oxime in Manganese Phosphinate and Phosphonate Chemistry. Inorg Chem 2017; 56:11352-11364. [PMID: 28853558 DOI: 10.1021/acs.inorgchem.7b01793] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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80
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Liu C, Felts AC, Takahashi D, Kinden WS, Abboud KA. Crystal structure of aqua- trans-bis-(dimethyl sulfoxide-κ O)(pyridine-2,6-di-carboxyl-ato-κ 3O2, N, O6)nickel(II). Acta Crystallogr E Crystallogr Commun 2017; 73:777-779. [PMID: 28529797 PMCID: PMC5418805 DOI: 10.1107/s2056989017006090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 04/22/2017] [Indexed: 11/14/2022]
Abstract
In the title complex, [Ni(C7H3NO4)(C2H6OS)2(H2O)], the NiII cation is situated on a twofold rotation axis and exhibits a distorted octa-hedral NO5 coordination environment defined by a tridentate pyridine-2,6-di-carb-oxy-lic acid dianion (dpa2-), two dimethyl sulfoxide (DMSO) mol-ecules, and a water mol-ecule. In the crystal, the complex mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds into a three-dimensional network whereby DMSO mol-ecules from neighboring complexes overlap to form layers parallel to (001), alternating with layers of NiII-dpa2- moieties. The title complex is isotypic with its cobalt(II) analogue.
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81
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Anderton KJ, Knight BJ, Rheingold AL, Abboud KA, García-Serres R, Murray LJ. Reactivity of hydride bridges in a high-spin [Fe 3(μ-H) 3] 3+ cluster: reversible H 2/CO exchange and Fe-H/B-F bond metathesis. Chem Sci 2017; 8:4123-4129. [PMID: 28603601 PMCID: PMC5443887 DOI: 10.1039/c6sc05583d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/27/2017] [Indexed: 01/08/2023] Open
Abstract
The triiron trihydride complex Fe3H3L (1) [where L3– is a tris(β-diketiminate)cyclophanate] reacts with CO and with BF3·OEt2 to afford (FeICO)2FeII(μ3-H)L (2) and Fe3F3L (3), respectively.
The triiron trihydride complex Fe3H3L (1) [where L3– is a tris(β-diketiminate)cyclophanate] reacts with CO and with BF3·OEt2 to afford (FeICO)2FeII(μ3-H)L (2) and Fe3F3L (3), respectively. Variable-temperature and applied-field Mössbauer spectroscopy support the assignment of two high-spin (HS) iron(i) centers and one HS iron(ii) ion in 2. Preliminary studies support a CO-induced reductive elimination of H2 from 1, rather than CO trapping a species from an equilibrium mixture. This complex reacts with H2 to regenerate 1 under a dihydrogen atmosphere, which represents a rare example of reversible CO/H2 exchange and the first to occur at high-spin metal centers, as well as the first example of a reversible multielectron redox reaction at a designed high-spin metal cluster. The formation of 3 proceeds through a previously unreported net fluoride-for-hydride substitution, and 3 is surprisingly chemically inert to Si–H bonds and points to an unexpectedly large difference between the Fe–F and Fe–H bonds in this high-spin system.
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82
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Yang X, VenkatRamani S, Beto CC, Del Castillo TJ, Ghiviriga I, Abboud KA, Veige AS. Single versus Double Cu(I) Catalyzed [3 + 2] Azide/Platinum Diacetylide Cycloaddition Reactions. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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83
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Paioti PHS, Abboud KA, Aponick A. Incorporation of Axial Chirality into Phosphino-Imidazoline Ligands for Enantioselective Catalysis. ACS Catal 2017. [DOI: 10.1021/acscatal.7b00133] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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84
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Fagnani DE, Meese MJ, Abboud KA, Castellano RK. Corrigendum: Homochiral [2.2]Paracyclophane Self‐Assembly Promoted by Transannular Hydrogen Bonding. Angew Chem Int Ed Engl 2017; 56:1441. [DOI: 10.1002/anie.201610870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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85
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Fagnani DE, Meese MJ, Abboud KA, Castellano RK. Berichtigung: Homochiral [2.2]Paracyclophane Self-Assembly Promoted by Transannular Hydrogen Bonding. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201610870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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86
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Pedziwiatr J, Ghiviriga I, Abboud KA, Veige AS. Crystal structures of a novel NNN pincer ligand and its dinuclear titanium(IV) alkoxide pincer complex. Acta Crystallogr E Crystallogr Commun 2017; 73:122-126. [PMID: 28217325 PMCID: PMC5290548 DOI: 10.1107/s2056989016019964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 12/15/2016] [Indexed: 11/10/2022]
Abstract
This report describes a synthetic protocols and the crystal structures involving a novel pincer-type H3[NNN] ligand, namely di-μ-bromido-μ-{2-(2,2-di-methylpropanimido-yl)-N-[2-(2,2-di-methyl-propanimido-yl)-4-methyl-phen-yl]-4-methylaniline}-bis-[(diethyl ether)lithium], [Li2Br2(C24H33N3)(C4H10O)2] (1) and a dinuclear metal complex, namely di-μ-bromido-2:3κ4Br:Br-bis-{2-(2,2-di-methylpropanimido-yl)-N-[2-(2,2-di-methyl-propanimido-yl)-4-methyl-phen-yl]-4-methylaniline}-1κ3N,N',N'';4κ3N,N',N''-tetra-μ-iso-propano-lato-1:2κ4O:O;3:4κ4O:O-diiso-propano-lato-1κO,4κO-2,3-dilithium-1,4-dititanium, [Li2Ti2Br2(C24H32N3)2(C3H7O)6] or {[NHNNH]Ti(O i Pr)3(LiBr)2}2 (2). Complex 1, which sits on a twofold rotation axis, is a rare example of a pincer-type ligand which bears ketimine side arms. A unique feature of complex 1 is that the ketimine N atoms have an LiBr(Et2O) fragment bonded to them, with the Li atom adopting a distorted tetra-hedral geometry. This particular fragment creates an LiBr bridge between the two ketimine sidearms, which leads to a cage-type appearance of the ligand. Complex 2 consists of the previously described ligand and a TiIV metal atom in an octa-hedral environment, and is located on an inversion center. Complex 2 crystallizes as a dinuclear species with the metal atoms being bridged by an LiBr entity [the Br atoms are disordered and refined in two positions with their site occupation factors refining to 0.674 (12)/0.372 (12)], and the Li cation being bonded to the isopropoxide O atoms (Li having a tetra-hedral coordination as in 1). The organic ligand of compound 2 exhibits disorder in its periphery groups; isopropyl and tert-butyl groups (occupation factors fixed at 0.6/0.4). The novel [NNN]H3 pincer-type ligand was characterized by multinuclear and multidimensional NMR, HRMS and X-ray crystallography. The dinuclear metal complex 2 was characterized by X-ray crystallography. Although each structure exhibits donor N-H groups, no hydrogen bonding is found in either one, perhaps due to the bulky groups around them. One of the ethyl groups of the ether ligand of 1 is disordered and refined in two parts with site-occupation factors of 0.812 (8) and 0.188 (8). One and a half toluene solvent mol-ecules are also present in the asymmetric unit of 2. The toluene mol-ecules were significantly disordered and could not be modeled properly, thus SQUEEZE [Spek (2015 ▸). Acta Cryst. C71, 9-18] was used to remove their contributions to the overall intensity data.
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Ferreira RB, Figueroa JM, Fagnani DE, Abboud KA, Castellano RK. Benzotrifuran (BTFuran): a building block for π-conjugated systems. Chem Commun (Camb) 2017; 53:9590-9593. [DOI: 10.1039/c7cc04505k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reported here is the first synthesis, X-ray crystal structure, and derivatization of C3h-symmetric benzotrifuran (BTFuran), oxygen analog of the widely exploited benzotrithiophene.
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88
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Adebayo OA, Abboud KA, Christou G. New mixed-valence MnII4MnIV clusters from an unusual ligand transformation. Polyhedron 2017. [DOI: 10.1016/j.poly.2016.10.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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89
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Ay B, Yildiz E, Felts AC, Abboud KA. Hydrothermal synthesis, structure, heterogeneous catalytic activity and photoluminescent properties of a novel homoleptic Sm(III)-organic framework. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2016.09.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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90
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Matsuura MF, Kim HJ, Takahashi D, Abboud KA, Benner SA. Crystal structures of deprotonated nucleobases from an expanded DNA alphabet. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2016; 72:952-959. [PMID: 27918296 DOI: 10.1107/s2053229616017071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 10/24/2016] [Indexed: 11/10/2022]
Abstract
Reported here is the crystal structure of a heterocycle that implements a donor-donor-acceptor hydrogen-bonding pattern, as found in the Z component [6-amino-5-nitropyridin-2(1H)-one] of an artificially expanded genetic information system (AEGIS). AEGIS is a new form of DNA from synthetic biology that has six replicable nucleotides, rather than the four found in natural DNA. Remarkably, Z crystallizes from water as a 1:1 complex of its neutral and deprotonated forms, and forms a `skinny' pyrimidine-pyrimidine pair in this structure. The pair resembles the known intercalated cytosine pair. The formation of the same pair in two different salts, namely poly[[aqua(μ6-2-amino-6-oxo-3-nitro-1,6-dihydropyridin-1-ido)sodium]-6-amino-5-nitropyridin-2(1H)-one-water (1/1/1)], denoted Z-Sod, {[Na(C5H4N3O3)(H2O)]·C5H5N3O3·H2O}n, and ammonium 2-amino-6-oxo-3-nitro-1,6-dihydropyridin-1-ide-6-amino-5-nitropyridin-2(1H)-one-water (1/1/1), denoted Z-Am, NH4+·C5H4N3O3-·C5H5N3O3·H2O, under two different crystallization conditions suggests that the pair is especially stable. Implications of this structure for the use of this heterocycle in artificial DNA are discussed.
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91
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Liu C, Thuijs AE, Abboud KA. Crystal structure of catena-poly[bis-(tetra-ethyl-ammonium) [tetra-aqua-tris(μ-dicyanamido-κ 2N1: N5)bis(dicyanamido-κ N1)di-cobaltate(II)] dicyanamide]. Acta Crystallogr E Crystallogr Commun 2016; 72:1603-1606. [PMID: 27840718 PMCID: PMC5095843 DOI: 10.1107/s2056989016016637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 10/17/2016] [Indexed: 11/10/2022]
Abstract
The structure of the title compound, [N(C2H5)4]2[Co2(C2N3)5(H2O)4](C2N3), is a new example of a metal-dicyanamide coordination polymer which exhibits a unique three-dimensional framework of covalently linked CoII chains. All bridging dicyanamide ligands in the title structure are in the μ1,5-bridging mode. The anionic CoII-dicyanamide network is templated by tetra-ethyl-ammonium cations residing in a series of channels extending along the b axis where additional non-coordinating dicyanamidate anions are also located. The framework structure is further stabilized by O-H⋯N hydrogen bonding between aqua ligands and dicyanamido ligands or the dicyanamide anion. In addition, C-H⋯N inter-actions are present between the tetra-ethyl-ammonium cations and dicyanamide amide nitro-gen atoms.
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Ermert DM, Gordon JB, Abboud KA, Murray LJ. Synthesis of Trinuclear Tin(II), Germanium(II), and Aluminum(III) Cyclophane Complexes. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00354] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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93
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Baker MB, Ferreira RB, Tasseroul J, Lampkins AJ, Al Abbas A, Abboud KA, Castellano RK. Selective and Sequential Aminolysis of Benzotrifuranone: Synergism of Electronic Effects and Ring Strain Gradient. J Org Chem 2016; 81:9279-9288. [DOI: 10.1021/acs.joc.6b01867] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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94
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Chakov NE, Thuijs AE, Wernsdorfer W, Rheingold AL, Abboud KA, Christou G. Unusual Mn(III/IV)4 Cubane and Mn(III)16M4 (M = Ca, Sr) Looplike Clusters from the Use of Dimethylarsinic Acid. Inorg Chem 2016; 55:8468-77. [PMID: 27504743 DOI: 10.1021/acs.inorgchem.6b01077] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Three complexes are reported from the initial use of dimethylarsinic acid (Me2AsO2H) in Mn(III/IV) cluster chemistry, [Mn4O4(O2AsMe2)6] (3; 2Mn(III), 2Mn(IV)), and [Mn16X4O8(O2CPh)16(Me2AsO2)24] (X = Ca(2+) (4) or Sr(2+) (5); 16Mn(III)). They were obtained from reactions with [Mn12O12(O2CR)16(H2O)4] (R = Me, Ph) either without (3) or with (4 and 5) the addition of X(2+) salts. Complex 3 contains a [Mn4O4](6+) cubane, whereas isostructural 4 and 5 contain a planar loop structure comprising four Mn4 asymmetric "butterfly" units linked by alternating anti,anti μ-O2AsMe2 and {X2(O2AsMe2)(O2CPh)2} units. Variable-temperature magnetic susceptibility (χM) data were collected on dried microcrystalline samples of 3-5 in the 5.0-300 K range in a 0.1 T (1000 G) direct-current (dc) magnetic field. Data for 3 were fit to the appropriate Van Vleck equation (using the [Formula: see text] = -2JŜi·Ŝj convention) for a cubane of virtual C2v symmetry, giving J33 = 0.0(1) cm(-1), J34 = -3.4(4) cm(-1), J44 = -9.8(2) cm(-1), and g = 1.99(1), where the Jij subscripts refer to the oxidation states of the interacting Mn atoms. The ground state thus consists of two coupled Mn(IV) and two essentially noninteracting Mn(III). For 4 and 5, low-lying excited states from the high nuclearity and weak couplings prevent fits of dc magnetization data, but in-phase alternating current susceptibility χ'MT data down to 1.8 K indicate them to possess S = 4 ground states, if considered single Mn16 units. If instead they are treated as tetramers of weakly coupled Mn4 units, then each of the latter has an S = 2 ground state. Complexes 4 and 5 also exhibit very weak out-of-phase χ″M signals characteristic of slow relaxation, and magnetization versus dc field scans on a single crystal of 4·15MeCN at T ≥ 0.04 K showed hysteresis loops but with unusual features suggesting the magnetization relaxation barrier consists of more than one contribution.
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Thiele NA, Abboud KA, Sloan KB. Novel double prodrugs of the iron chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED): Synthesis, characterization, and investigation of activation by chemical hydrolysis and oxidation. Eur J Med Chem 2016; 118:193-207. [PMID: 27128183 DOI: 10.1016/j.ejmech.2016.04.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 03/23/2016] [Accepted: 04/13/2016] [Indexed: 11/26/2022]
Abstract
The development of iron chelators suitable for the chronic treatment of diseases where iron accumulation and subsequent oxidative stress are implicated in disease pathogenesis is an active area of research. The clinical use of the strong chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED) and its alkyl ester prodrugs has been hindered by poor oral bioavailability and lack of conversion to the parent chelator, respectively. Here, we present novel double prodrugs of HBED that have the carboxylate and phenolate donors of HBED masked with carboxylate esters and boronic acids/esters, respectively. These double prodrugs were successfully synthesized as free bases (7a-f) or as dimesylate salts (8a-c,e), and were characterized by (1)H, (13)C, and (11)B NMR; MP; MS; and elemental analysis. The crystal structure of 8a was solved. Three of the double prodrugs (8a-c) were selected for further investigation into their abilities to convert to HBED by stepwise hydrolysis and H2O2 oxidation. The serial hydrolysis of the pinacol and methyl esters of N,N'-bis(2-boronic acid pinacol ester benzyl)ethylenediamine-N,N'-diacetic acid methyl ester dimesylate (8a) was verified by LC-MS. The macro half-lives for the hydrolyses of 8a-c, measured by UV, ranged from 3.8 to 26.3 h at 37 °C in pH 7.5 phosphate buffer containing 50% MeOH. 9, the product of hydrolysis of 8a-c and the intermediate in the conversion pathway, showed little-to-no affinity for iron or copper in UV competition experiments. 9 underwent a serial oxidative deboronation by H2O2 in N-methylmorpholine buffer to generate HBED (k = 10.3 M(-1) min(-1)). The requirement of this second step, oxidation, before conversion to the active chelator is complete may confer site specificity when only localized iron chelation is needed. Overall, these results provide proof of principle for the activation of the double prodrugs by chemical hydrolysis and H2O2 oxidation, and merit further investigation into the protective capabilities of the prodrugs against H2O2-induced cell death.
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Fagnani DE, Meese MJ, Abboud KA, Castellano RK. Homochiral [2.2]Paracyclophane Self‐Assembly Promoted by Transannular Hydrogen Bonding. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605286] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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97
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Fagnani DE, Meese MJ, Abboud KA, Castellano RK. Homochiral [2.2]Paracyclophane Self‐Assembly Promoted by Transannular Hydrogen Bonding. Angew Chem Int Ed Engl 2016; 55:10726-31. [DOI: 10.1002/anie.201605286] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Indexed: 11/08/2022]
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98
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Lee Y, Abboud KA, García-Serres R, Murray LJ. A three-coordinate Fe(ii) center within a [3Fe-(μ3-S)] cluster that provides an accessible coordination site. Chem Commun (Camb) 2016; 52:9295-8. [PMID: 27363672 DOI: 10.1039/c6cc04671a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A μ3-sulfide bridged triiron cluster(ii,ii,iii) supported by a cyclophane ligand undergoes metal-based reduction to yield an all-ferrous species. The latter complex incorporates a three-coordinate iron center that provides an accessible coordination site to a solvent molecule.
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VenkatRamani S, Roland CD, Zhang JG, Ghiviriga I, Abboud KA, Veige AS. Trianionic Pincer Complexes of Niobium and Tantalum as Precatalysts for ROMP of Norbornene. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00421] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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100
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Frasco DA, Mukherjee S, Sommer RD, Perry CM, Lambic NS, Abboud KA, Jakubikova E, Ison EA. Nondirected C–H Activation of Arenes with Cp*Ir(III) Acetate Complexes: An Experimental and Computational Study. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00308] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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