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González SR, Aragó J, Viruela PM, Ortí E, López Navarrete JT, Sato MA, Casado J. Diferrocenyl oligothiophene wires: Raman and quantum chemical study of valence-trapped cations. J Chem Phys 2011; 135:234705. [DOI: 10.1063/1.3669653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Aragó J, Ponce Ortiz R, Nieto-Ortega B, Hernández V, Casado J, Facchetti A, Marks TJ, Viruela PM, Ortí E, López Navarrete JT. Carbonyl-Functionalized Quaterthiophenes: A Study of the Vibrational Raman and Electronic Absorption/Emission Properties Guided by Theoretical Calculations. Chemphyschem 2011; 13:168-76. [DOI: 10.1002/cphc.201100736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Indexed: 11/07/2022]
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González SR, Ie Y, Aso Y, López Navarrete JT, Casado J. The Frontiers of Quinoidal Stability in Long Oligothiophenes: Raman Spectra of Dicationic Polaron Pairs. J Am Chem Soc 2011; 133:16350-3. [DOI: 10.1021/ja2061903] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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179
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Nieto-Ortega B, Casado J, López Navarrete JT, Hennrich G, Ramírez FJ. On the Origin of the Chiro-Optical Activity in Supramolecular Assemblies: A Quantum Chemical Study of C3 Octopolar Systems. J Chem Theory Comput 2011; 7:3314-22. [DOI: 10.1021/ct200505s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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González SR, Orduna J, Alicante R, Villacampa B, McGee KA, Pina J, Seixas de Melo J, Schwaderer KM, Johnson JC, Blackorbay BA, Hansmeier JJ, Bolton VF, Helland TJ, Edlund BA, Pappenfus TM, López Navarrete JT, Casado J. Understanding Optoelectronic Properties of Cyano-Terminated Oligothiophenes in the Context of Intramolecular Charge Transfer. J Phys Chem B 2011; 115:10573-85. [DOI: 10.1021/jp2070375] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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181
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Juárez R, Oliva MM, Ramos M, Segura JL, Alemán C, Rodríguez-Ropero F, Curcó D, Montilla F, Coropceanu V, Brédas JL, Qi Y, Kahn A, Ruiz Delgado MC, Casado J, López Navarrete JT. Hexaazatriphenylene (HAT) versus tri-HAT: The Bigger the Better? Chemistry 2011; 17:10312-22. [DOI: 10.1002/chem.201101198] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Indexed: 11/10/2022]
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182
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Nieto-Ortega B, Casado J, Blanch EW, López Navarrete JT, Quesada AR, Ramírez FJ. Raman optical activity spectra and conformational elucidation of chiral drugs. The case of the antiangiogenic aeroplysinin-1. J Phys Chem A 2011; 115:2752-5. [PMID: 21401047 DOI: 10.1021/jp2009397] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present the determination of the conformational properties of aeroplysinin-1 in aqueous solution by means of a combined experimental and theoretical Raman optical activity (ROA) and vibrational circular dichroism (VCD) study. Aeroplysinin-1 is an antiangiogenic drug extracted from the sponge Aplysina cavernicola which has been proved to be a valuable candidate for the treatment of cancer and other antiangiogenic diseases. Our study shows that this molecule possesses the 1S,6R absolute configuration in aqueous solution, where only two conformers are present to a significant level. We discuss in detail the relationships between the chiro-optical ROA and VCD features, and the structural properties of various energy accessible conformers are described. The present work is one of the first studies in which both ROA and VCD have been used as complementary tools for the determination of absolute configuration and dominant solution-state conformations of an unknown therapeutically significant molecule.
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Rivera-Fuentes P, Nieto-Ortega B, Schweizer WB, López Navarrete JT, Casado J, Diederich F. Enantiopure, Monodisperse Alleno-acetylenic Cyclooligomers: Effect of Symmetry and Conformational Flexibility on the Chiroptical Properties of Carbon-Rich Compounds. Chemistry 2011; 17:3876-85. [DOI: 10.1002/chem.201100131] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Indexed: 11/11/2022]
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Pérez Suárez E, Carceller F, García Salido A, Serrano A, Casado J. [Chance fracture missed by convencional CT: Presentation of a clinical course]. ARCH ARGENT PEDIATR 2011; 109:13-16. [PMID: 21283937 DOI: 10.1590/s0325-00752011000100018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 10/08/2010] [Indexed: 05/30/2023]
Abstract
INTRODUCTION Bending-disruption fractures of the vertebral body are called Chance fracture. In some cases these fractures may not be noticeable with a CT scan. CLINICAL CASE A 9 years-old boy suffered a frontal collision while traveling in the back seat of a car. The child was secured by the safetybelt, without a child car seat or elevator adapted to his height. He had abdominal skin lesions in the physical exploration compatible with a belt mark. Conventional thoraco- abdominal CT scan did not show any vertebral fracture. As the clinical suspicion persisted, lateral plain radiography of the lumbar column was performed showing a Chance fracture in L2, confirmed by MRI. CONCLUSION Chance fracture is typically seen in children under 12 years less than 135 cm height and with injuries associated with the belt after a traffic accident. This type of fractures may go unnoticed in a conventional CT scan so clinical suspicion must lead us to further work-up. The MRI is the gold standard for the diagnosis. This case remarks the importance of the use of homologated elevated seat devices in older children.
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Zafra JL, Casado J, Perepichka II, Perepichka IF, Bryce MR, Ramírez FJ, Navarrete JTL. π-conjugation and charge polarization in fluorene-dibenzothiophene-S,S-dioxide co-oligomers by Raman spectroscopy and quantum chemistry. J Chem Phys 2011; 134:044520. [DOI: 10.1063/1.3526487] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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186
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Andreu R, Galán E, Orduna J, Villacampa B, Alicante R, Navarrete JTL, Casado J, Garín J. Aromatic/proaromatic donors in 2-dicyanomethylenethiazole merocyanines: from neutral to strongly zwitterionic nonlinear optical chromophores. Chemistry 2010; 17:826-38. [PMID: 21226097 DOI: 10.1002/chem.201002158] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Indexed: 11/12/2022]
Abstract
Push-pull compounds, in which a proaromatic electron donor is conjugated to a 2-dicyanomethylenethiazole acceptor, have been prepared, and their properties compared to those of model compounds featuring an aromatic donor. A combined experimental (X-ray diffraction, (1) H NMR, IR, Raman, UV/Vis, nonlinear optical (NLO) measurements) and theoretical study reveals that structural and solvent effects determine the ground-state polarisation of these merocyanines: whereas 4H-pyran-4-ylidene- and 4-pyridylidene-containing compounds are zwitterionic and 1,3-dithiol-2-ylidene derivatives are close to the cyanine limit, anilino-derived merocyanines are essentially neutral. This very large range of intramolecular charge transfer (ICT) gives rise to efficient second-order NLO chromophores with μβ values ranging from strongly negative to strongly positive. In particular, pyranylidene derivatives are unusual in that they show an increase in the degree of ICT on lengthening the π-spacer, a feature that lies behind the very large negative μβ values they display. The linking of the formally quinoidal 2-dicyanomethylenethiazole moiety to proaromatic donors seems a promising approach towards the optimisation of zwitterionic NLO chromophores.
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Collado D, Casado J, González SR, Navarrete JTL, Suau R, Perez‐Inestrosa E, Pappenfus TM, Raposo MMM. Enhanced Functionality for Donor–Acceptor Oligothiophenes by means of Inclusion of BODIPY: Synthesis, Electrochemistry, Photophysics, and Model Chemistry. Chemistry 2010; 17:498-507. [DOI: 10.1002/chem.201001942] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Indexed: 11/12/2022]
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188
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Iavicoli P, Xu H, Feldborg LN, Linares M, Paradinas M, Stafström S, Ocal C, Nieto-Ortega B, Casado J, López Navarrete JT, Lazzaroni R, De Feyter S, Amabilino DB. Tuning the supramolecular chirality of one- and two-dimensional aggregates with the number of stereogenic centers in the component porphyrins. J Am Chem Soc 2010; 132:9350-62. [PMID: 20560581 DOI: 10.1021/ja101533j] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A synthetic strategy was developed for the preparation of porphyrins containing between one and four stereogenic centers, such that their molecular weights vary only as a result of methyl groups which give the chiral forms. The low-dimensional nanoscale aggregates of these compounds reveal the profound effects of this varying molecular chirality on their supramolecular structure and optical activity. The number of stereogenic centers influences significantly the self-assembly and chiral structure of the aggregates of porphyrin molecules described here. A scanning tunneling microscopy study of monolayers on graphite shows that the degree of structural chirality with respect to the surface increases almost linearly with the number of stereogenic centers, and only one handedness is formed in the monolayers, whereas the achiral compound forms a mixture of mirror-image domains at the surface. In solution, four hydrogen bonds induce the formation of an H-aggregate, and circular dichroism measurements and theoretical studies indicate that the compounds self-assemble into helical structures. Both the chirality and stability of the aggregates depend critically on the number of stereocenters. The chiral porphyrin derivatives gelate methylcyclohexane at concentrations dependent on the number and position of chiral groups at the periphery of the aromatic core, reflecting the different aggregation forces of the molecules in solution. Increasing the number of stereogenic centers requires more material to immobilize the solvent, in all likelihood because of the greater solubility of the porphyrins. The vibrational circular dichroism spectra of the gels show that all compounds have a chiral environment around the amide bonds, confirming the helical model proposed by calculations. The morphologies of the xerogels (studied by scanning electron microscopy and scanning force microscopy) are similar, although more fibrous features are present in the molecules with fewer stereogenic centers. Importantly, the presence of only one stereogenic center, bearing a methyl group as the desymmetrizing ligand, in a molecule of considerable molecular weight is enough to induce single-handed chirality in both the one- and two-dimensional supramolecular self-assembled structures.
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Antelo JM, Arce F, Casado J, Castro R, Sanchez ME, Varela A. The Influence of PH on the Stability of N-Chloro-2-Ethylaminoethanol. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bscb.19840930105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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190
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Casado J, Mosquera M, Rodr ÍGuez Prieto MF, Vázquez Tato J. The Kinetics and Mechanism of Reactions Between the Nitroprusside Ion and Secondary Amines. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19850890704] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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191
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Casado J, Quintela MAL, Mosquera M, Rodr Prieto MFÍ, Tato JV. The Nitroprusside Ion as a Nitrosating Reagent. Kinetic Studies on the Nitrosation of Morpholine. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19830871225] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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192
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Casado J, Castro A, Mosquera M, Rodr Prieto MFÍ, Tato JV. The Reaction Mechanism of the Nitrosation of Ureas. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19830871226] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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193
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Schmidt A, Lindner A, Casado J, López Navarrete J, Ramírez F. Mesomeric betaine chemistry in solution: Solvent effect on the structure and spectra of uracilyl–pyridinium betaine. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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194
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Oliva MM, Pappenfus T, Melby J, Schwaderer K, Johnson J, McGee K, da Silva Filho D, Bredas JL, Casado J, López Navarrete J. Comparison of Thiophene-Pyrrole Oligomers with Oligothiophenes: A Joint Experimental and Theoretical Investigation of Their Structural and Spectroscopic Properties. Chemistry 2010; 16:6866-76. [DOI: 10.1002/chem.201000143] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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195
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Oliva MM, Casado J, Navarrete JTL, Patchkovskii S, Goodson T, Harpham MR, Seixas de Melo JS, Amir E, Rozen S. Do [all]-S,S′-Dioxide Oligothiophenes Show Electronic and Optical Properties of Oligoenes and/or of Oligothiophenes? J Am Chem Soc 2010; 132:6231-42. [DOI: 10.1021/ja101015q] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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196
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Nieto B, Ramírez FJ, Hennrich G, Gómez-Lor B, Casado J, Navarrete JTL. Aggregation Behavior of a Conjugated C3-Symmetric Molecule: A Description Based on Chiro-Optical Experimental and Theoretical Spectroscopies. J Phys Chem B 2010; 114:5710-7. [DOI: 10.1021/jp100628s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ponceâ
Ortiz R, Casado J, RodrÃguezâ
González S, Hernández VÃ, Lópezâ
Navarreteâ J, Viruela P, OrtÃâ E, Takimiya K, Otsubo T. Quinoidal Oligothiophenes: Towards Biradical Ground-State Species. Chemistry 2010; 16:470-84. [DOI: 10.1002/chem.200902037] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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198
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Oliva M, Casado J, López Navarrete J, Hennrich G, van Cleuvenbergen S, Asselberghs I, Clays K, Ruiz Delgado M, Brédas JL, Seixas de Melo J, De Cola L. Synthesis, Spectroscopy, Nonlinear Optics, and Theoretical Investigations of Thienylethynyl Octopoles with a Tunable Core. Chemistry 2009; 15:8223-34. [DOI: 10.1002/chem.200900702] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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199
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Ponce Ortiz R, González SR, Casado J, López Navarrete JT, Officer DL, Wagner P, Earles JC, Gordon KC. Electronic Studies on Oligothienylenevinylenes: Understanding the Nature of Their Ground and Excited Electronic States. Chemphyschem 2009; 10:1901-10. [DOI: 10.1002/cphc.200900140] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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200
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Ortiz RP, Casado J, Hernández V, Navarrete JL, Letizia J, Ratner M, Facchetti A, Marks T. Cover Picture: Thiophene-Diazine Molecular Semiconductors: Synthesis, Structural, Electrochemical, Optical, and Electronic Structural Properties; Implementation in Organic Field-Effect Transistors (Chem. Eur. J. 20/2009). Chemistry 2009. [DOI: 10.1002/chem.200990069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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