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Aschi M, Toto Brocchi G, Portalone G. A Combined Experimental and Computational Study of Halogen and Hydrogen Bonding in Molecular Salts of 5-Bromocytosine. Molecules 2021; 26:molecules26113111. [PMID: 34070959 PMCID: PMC8196974 DOI: 10.3390/molecules26113111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/11/2021] [Accepted: 05/17/2021] [Indexed: 11/16/2022] Open
Abstract
Although natural or artificial modified pyrimidine nucleobases represent important molecules with valuable properties as constituents of DNA and RNA, no systematic analyses of the structural aspects of bromo derivatives of cytosine have appeared so far in the literature. In view of the biochemical and pharmaceutical relevance of these compounds, six different crystals containing proton-transfer derivatives of 5-bromocytosine are prepared and analyzed in the solid-state by single crystal X-ray diffraction. All six compounds are organic salts, with proton transfer occurring to the Nimino atom of the pyridine ring. Experimental results are then complemented with Hirshfeld surface analysis to quantitively evaluate the contribution of different intermolecular interactions in the crystal packing. Furthermore, theoretical calculations, based on different arrangements of molecules extracted from the crystal structure determinations, are carried out to analyze the formation mechanism of halogen bonds (XBs) in these compounds and provide insights into the nature and strength of the observed interactions. The results show that the supramolecular architectures of the six molecular salts involve extensive classical intermolecular hydrogen bonds. However, in all but one proton-transfer adducts, weak to moderate XBs are revealed by C-Br…O short contacts between the bromine atom in the fifth position, which acts as XB donor (electron acceptor). Moreover, the lone pair electrons of the oxygen atom of adjacent pyrimidine nucleobases and/or counterions or water molecules, which acts as XB acceptor (electron donor).
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Affiliation(s)
- Massimiliano Aschi
- Dipartimento di Scienze Fisiche e Chimiche, Università degli Studi di L’Aquila, Via Vetoio 10, 67100 Coppito, Italy;
| | - Giorgia Toto Brocchi
- Dipartimento di Chimica, Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Roma, Italy;
| | - Gustavo Portalone
- Dipartimento di Chimica, Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Roma, Italy;
- Correspondence:
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Anyfanti G, Bauzá A, Gentiluomo L, Rodrigues J, Portalone G, Frontera A, Rissanen K, Puttreddy R. Short X···N Halogen Bonds With Hexamethylenetetraamine as the Acceptor. Front Chem 2021. [DOI: https://doi.org/10.3389/fchem.2021.623595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hexamethylenetetramine (HMTA) and N-haloimides form two types of short (imide)X···N and X–X···N (X = Br, I) halogen bonds. Nucleophilic substitution or ligand-exchange reaction on the peripheral X of X–X···N with the chloride of N-chlorosuccinimide lead to Cl–X···N halogen-bonded complexes. The 1:1 complexation of HMTA and ICl manifests the shortest I···N halogen bond [2.272(5) Å] yet reported for an HMTA acceptor. Two halogen-bonded organic frameworks are prepared using 1:4 molar ratio of HMTA and N-bromosuccinimide, each with a distinct channel shape, one possessing oval and the other square grid. The variations in channel shapes are due to tridentate and tetradentate (imide)Br···N coordination modes of HMTA. Density Functional Theory (DFT) studies are performed to gain insights into (imide)X···N interaction strengths (ΔEint). The calculated ΔEint values for (imide)Br···N (−11.2 to −12.5 kcal/mol) are smaller than the values for (imide)I···N (−8.4 to −29.0 kcal/mol). The DFT additivity analysis of (imide)Br···N motifs demonstrates Br···N interaction strength gradually decreasing from 1:1 to 1:3 HMTA:N-bromosuccinimide complexes. Exceptionally similar charge density values ρ(r) for N–I covalent bond and I···N non-covalent bond of a (saccharin)N–I···N motif signify the covalent character for I···N halogen bonding.
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Anyfanti G, Bauzá A, Gentiluomo L, Rodrigues J, Portalone G, Frontera A, Rissanen K, Puttreddy R. Short X···N Halogen Bonds With Hexamethylenetetraamine as the Acceptor. Front Chem 2021; 9:623595. [PMID: 33996740 PMCID: PMC8116742 DOI: 10.3389/fchem.2021.623595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/01/2021] [Indexed: 02/05/2023] Open
Abstract
Hexamethylenetetramine (HMTA) and N-haloimides form two types of short (imide)X···N and X-X···N (X = Br, I) halogen bonds. Nucleophilic substitution or ligand-exchange reaction on the peripheral X of X-X···N with the chloride of N-chlorosuccinimide lead to Cl-X···N halogen-bonded complexes. The 1:1 complexation of HMTA and ICl manifests the shortest I···N halogen bond [2.272(5) Å] yet reported for an HMTA acceptor. Two halogen-bonded organic frameworks are prepared using 1:4 molar ratio of HMTA and N-bromosuccinimide, each with a distinct channel shape, one possessing oval and the other square grid. The variations in channel shapes are due to tridentate and tetradentate (imide)Br···N coordination modes of HMTA. Density Functional Theory (DFT) studies are performed to gain insights into (imide)X···N interaction strengths (ΔEint). The calculated ΔEint values for (imide)Br···N (-11.2 to -12.5 kcal/mol) are smaller than the values for (imide)I···N (-8.4 to -29.0 kcal/mol). The DFT additivity analysis of (imide)Br···N motifs demonstrates Br···N interaction strength gradually decreasing from 1:1 to 1:3 HMTA:N-bromosuccinimide complexes. Exceptionally similar charge density values ρ(r) for N-I covalent bond and I···N non-covalent bond of a (saccharin)N-I···N motif signify the covalent character for I···N halogen bonding.
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Affiliation(s)
- Goulielmina Anyfanti
- Department of Chemistry, University of Jyvaskyla, Jyvaskyla, Finland
- Centro de Química da Madeira, MMRG, Universidade da Madeira, Funchal, Portugal
| | - Antonio Bauzá
- Department of Chemistry, Universitat de les Illes Balears, Palma de Mallorca (Balearus), Spain
| | - Lorenzo Gentiluomo
- Department of Chemistry, University of Jyvaskyla, Jyvaskyla, Finland
- Department of Chemistry, “La Sapienza” University of Rome, Rome, Italy
| | - João Rodrigues
- Centro de Química da Madeira, MMRG, Universidade da Madeira, Funchal, Portugal
| | - Gustavo Portalone
- Department of Chemistry, “La Sapienza” University of Rome, Rome, Italy
| | - Antonio Frontera
- Department of Chemistry, Universitat de les Illes Balears, Palma de Mallorca (Balearus), Spain
- *Correspondence: Antonio Frontera
| | - Kari Rissanen
- Department of Chemistry, University of Jyvaskyla, Jyvaskyla, Finland
- Kari Rissanen
| | - Rakesh Puttreddy
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
- Rakesh Puttreddy
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Portalone G. Crystal structure and Hirshfeld surface analysis of a third polymorph of 2,6-di-meth-oxy-benzoic acid. Acta Crystallogr E Crystallogr Commun 2020; 76:1823-1826. [PMID: 33520261 PMCID: PMC7784654 DOI: 10.1107/s2056989020014553] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 11/03/2020] [Indexed: 11/29/2022]
Abstract
A third monoclinic polymorph of 2,6-dimethoxybnzoic acid is reported. The acidic O—H bond of the carboxyl group adopts a synplanar conformation. A third crystalline form of the title compound, C9H10O4, crystallizing in the centrosymmetric monoclinic space group P21/c, has been identified during screening for co-crystals. The asymmetric unit comprises a non-planar independent molecule with a synplanar conformation of the OH group. The sterically bulky o-methoxy substituents force the carboxy group to be twisted away from the plane of the benzene ring by 74.10 (6)°. The carboxy group exhibits the acidic H atom disordered over two sites between two O atoms. A similar situation has been found for the second tetragonal polymorph reported [Portalone (2011 ▸). Acta Cryst. E67, o3394–o3395], in which molecules with the OH group in a synplanar conformation form dimeric units via strong O—H⋯O hydrogen bonds. In contrast, in the first orthorhombic form reported [Swaminathan et al. (1976 ▸). Acta Cryst. B32, 1897–1900; Bryan & White (1982 ▸). Acta Cryst. B38, 1014–1016; Portalone (2009 ▸). Acta Cryst. E65, o327–o328], the molecular components do not form conventional dimeric units, as an antiplanar conformation adopted by the OH group favors the association of molecules in chains stabilized by linear O—H⋯O hydrogen bonds.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P. le A. Moro 5, I-00185 Rome, Italy
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Klisurić OR, Armaković SJ, Armaković S, Marković S, Todorović TR, Portalone G, Novović K, Lozo J, Filipović NR. Structural, biological and in-silico study of quinoline-based chalcogensemicarbazones. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Arcadi A, Aschi M, Chiarini M, Marinelli F, Marsicano V, Portalone G. Experimental results and computational insight into sequential reactions of β-(2-aminophenyl)-α,β-ynones with aryl isocyanates/benzoyl isothiocyanate. Org Biomol Chem 2020; 18:3177-3189. [DOI: 10.1039/d0ob00087f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The selective formation of quinazoline vs. benzoxazine and benzothiazine derivatives from β-(2-aminophenyl)-α,β-ynones and aryl isocyanates/benzoyl isothiocyanate was explored. DFT calculations provide a plausible rationale.
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Affiliation(s)
- Antonio Arcadi
- Dipartimento di Scienze Fisiche e Chimiche Università degli Studi di L'Aquila
- 67100 Coppito
- Italy
| | - Massimiliano Aschi
- Dipartimento di Scienze Fisiche e Chimiche Università degli Studi di L'Aquila
- 67100 Coppito
- Italy
| | - Marco Chiarini
- Facoltà di Bioscienze e Tecnologie Agro-alimentari e Ambientali
- Università di Teramo
- 64100 Teramo
- Italy
| | - Fabio Marinelli
- Dipartimento di Scienze Fisiche e Chimiche Università degli Studi di L'Aquila
- 67100 Coppito
- Italy
| | - Vincenzo Marsicano
- Dipartimento di Scienze Fisiche e Chimiche Università degli Studi di L'Aquila
- 67100 Coppito
- Italy
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Klisuric O, Armakovic S, Armakovic S, Markovic S, Todorovic T, Portalone G, Filipovic N. Structural and computational study of quinoline-based chalcogensemicarbazones. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319089903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abstract
6-Methyluracil, C5H6N2O2, exists in two crystalline phases: form (I), monoclinic, space group P21/c [Reck et al. (1988). Acta Cryst. A44, 417–421] and form (II), monoclinic, space group C2/c [Leonidov et al. (1993). Russ. J. Phys. Chem.
67, 2220–2223]. The structure of polymorph (II) has been redetermined providing a significant increase in the precision of the derived geometric parameters. In the crystal, molecules form ribbons approximately running parallel to the c-axis direction through N—H...O hydrogen bonds. The radical differences observed between the crystal packing of the two polymorphs may be responsible in form (II) for an increase in the contribution of the polar canonical forms C—(O−)=N—H+ relative to the neutral canonical form C(=O)—N—H induced by hydrogen-bonding interactions.
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Righi G, Pelagalli R, Isoni V, Tirotta I, Marini M, Palagri M, Dallocchio R, Dessì A, Macchi B, Frezza C, Forte G, Dalla Cort A, Portalone G, Bovicelli P. Synthesis of potential HIV integrase inhibitors inspired by natural polyphenol structures. Nat Prod Res 2017; 32:1893-1901. [DOI: 10.1080/14786419.2017.1354191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Giuliana Righi
- Department of Chemistry, CNR-IBPM, “Sapienza” Universy of Rome, Rome, Italy
| | - Romina Pelagalli
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | - Valerio Isoni
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | - Ilaria Tirotta
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | - Martina Marini
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | - Matteo Palagri
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | | | | | - Beatrice Macchi
- Department of System Medicine, “Tor Vergata” University, Rome, Italy
| | - Caterina Frezza
- Department of System Medicine, “Tor Vergata” University, Rome, Italy
| | - Gianpiero Forte
- Department of Chemistry, “Sapienza Universy of Rome, Roma, Italy
| | | | | | - Paolo Bovicelli
- Department of Chemistry, CNR-IBPM, “Sapienza” Universy of Rome, Rome, Italy
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Abstract
Fluoro-substituted flavones and 2-styrykhromones, related to natural and synthetic flavonoids previously described, were prepared, characterized and tested for anti-rhinovirus activity. Structural elucidation of the new compounds was performed by IR, NMR spectra and X-ray crystal structure analysis for 6-fluoro-3-hydroxy-2-styrylchromone. The antiviral potency was evaluated by a plaque reduction assay in HeLa cell cultures infected with rhinoviruses 1B and 14, selected as representative serotypes for viral groups B and A of human rhinoviruses, respectively. In comparison with results previously obtained, the introduction of the fluorine atom seems to exert a positive influence on the activity against serotype 14 while counteracting the effect against serotype 1B.
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Affiliation(s)
- Cinzia Conti
- Dipartimento di Scienze di Sanitá Pubblica, Sezione di Microbiologia, Universitá La Sapienza di Roma, Roma, Italy
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Todorović TR, Vukašinović J, Portalone G, Suleiman S, Gligorijević N, Bjelogrlić S, Jovanović K, Radulović S, Anđelković K, Cassar A, Filipović NR, Schembri-Wismayer P. (Chalcogen)semicarbazones and their cobalt complexes differentiate HL-60 myeloid leukaemia cells and are cytotoxic towards tumor cell lines. Medchemcomm 2016; 8:103-111. [PMID: 30108695 DOI: 10.1039/c6md00501b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 10/18/2016] [Indexed: 12/18/2022]
Abstract
Cobalt complexes with semi- and thiosemicarbazones of 8-quinolinecarboxaldehyde have been synthesized and characterized by X-ray diffraction analysis. These novel complexes and a previously synthesized cobalt complex with a selenium-based selenosemicarbazone ligand showed myeloid differentiation activity on all trans retinoic acid resistant HL-60 acute myeloid leukaemia cells. They also showed varying levels of cytotoxicity on five human tumor cell lines: cervix carcinoma cells (HeLa), lung adenocarcinoma cells (A549), colorectal adenocarcinoma cells (LS-174), breast carcinoma cells (MDA-MB-361), and chronic myeloid leukaemia (K562) as well as one normal human cell line: fetal lung fibroblast cells (MRC-5). Leukaemia differentiation was most strongly induced by a metal-free oxygen ligand and the selenium ligand, whilst the latter and the cobalt(ii) complex with an oxygen ligand showed the strongest dose-dependent cytotoxic activity. In four out of five investigated tumor cell lines, it was of the same order of magnitude as cisplatin. These best compounds, however, had lower toxicity on non-transformed MRC-5 cells than cisplatin.
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Affiliation(s)
- Tamara R Todorović
- Faculty of Chemistry , University of Belgrade , Studentski trg 12-16 , 11000 Belgrade , Serbia
| | - Jelena Vukašinović
- Faculty of Chemistry , University of Belgrade , Studentski trg 12-16 , 11000 Belgrade , Serbia
| | - Gustavo Portalone
- Department of Chemistry , Sapienza University of Rome , P.le Aldo Moro 5 , 00185 Rome , Italy
| | - Sherif Suleiman
- Anatomy Department , Faculty of Medicine and Surgery , University of Malta , Malta .
| | - Nevenka Gligorijević
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Snezana Bjelogrlić
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Katarina Jovanović
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Siniša Radulović
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Katarina Anđelković
- Faculty of Chemistry , University of Belgrade , Studentski trg 12-16 , 11000 Belgrade , Serbia
| | - Analisse Cassar
- Anatomy Department , Faculty of Medicine and Surgery , University of Malta , Malta .
| | - Nenad R Filipović
- Faculty of Agriculture , University of Belgrade , Nemanjina 6 , 11081 Belgrade , Serbia .
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Filipović NR, Bjelogrlić S, Portalone G, Pelliccia S, Silvestri R, Klisurić O, Senćanski M, Stanković D, Todorović TR, Muller CD. Pro-apoptotic and pro-differentiation induction by 8-quinolinecarboxaldehyde selenosemicarbazone and its Co(iii) complex in human cancer cell lines. Med Chem Commun 2016. [DOI: 10.1039/c6md00199h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The ligand initiated reprogramming of cancer stem cells phenotype in AsPC-1 cells. The complex digested plasmid DNA which might be the cause of its cytotoxic activity.
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Affiliation(s)
| | | | | | - Sveva Pelliccia
- Dipartimento di Chimica e Tecnologie del Farmaco
- Sapienza Universita di Roma
- I-00185 Roma
- Italy
| | - Romano Silvestri
- Dipartimento di Chimica e Tecnologie del Farmaco
- Sapienza Universita di Roma
- I-00185 Roma
- Italy
| | - Olivera Klisurić
- Department of Physics, Faculty of Sciences
- University of Novi Sad
- Novi Sad
- Serbia
| | - Milan Senćanski
- Center for Multidisciplinary Research
- Institute of Nuclear Sciences “Vinča”
- University of Belgrade
- Belgrade
- Serbia
| | - Dalibor Stanković
- Innovation Center of the Faculty of Chemistry
- University of Belgrade
- Belgrade
- Serbia
| | | | - Christian D. Muller
- Institut Pluridisciplinaire Hubert Curien
- UMR 7178 CNRS Université de Strasbourg
- 67401 Illkirch
- France
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Colapietro M, Domenicano A, Marciante C, Portalone G. Structural Studies of Benzene Derivatives, XII [1]. The Molecular Structure of 3,5-Dimethylbenzoic Acid in the Crystal, and a Comparison with the Gas Phase Structure of Related Molecules. Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-1984-1011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The molecular structure of 3,5-dimethylbenzoic acid has been accurately determ ined by X-ray crystallography. The crystals are monoclinic, space group P21/n, with a = 8.165(2), b = 6.992(1), c = 14.422(2) Å , β = 93.21(2)°, Z = 4. The structure has been refined by full-matrix least-squares techniques to R = 0.0415 on 1662 counter intensities. The carbon skeleton of the benzene ring has C2v symmetry within experimental error. The six aromatic C-C bond distances do not differ significantly from each other; some of the internal ring angles, however, deviate from 120° by as much as 2°. After correction for systematic effects, such as the asphericities of the electron density distribution and the libration of the molecule in the crystal, the mean aromatic C-C bond distance is 1.401(1) Å , and the two independent C-CH3 bond distances are 1.509 and 1.511(3) Å. These values are in outstanding agreement with the corresponding rg distances measured by gas electron diffraction in p-xylene (1.400±0.003 Å and 1.512±0.003 Å , respectively) and mesitylene (1.401 ±0.002 A and 1.509±0.002 Å, respectively). The deviations of the ring angles from 120° are interpreted fairly well as arising from the superposition of separate, independent angular distortions from each substituent.
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Affiliation(s)
- Marcello Colapietro
- Department of Chemistry, University of Rome “La Sapienza” , 1-00185 Rome, and Institute of Structural Chemistry, CNR, 1-00016 Monterotondo Stazione, Italy
| | - Aldo Domenicano
- Department of Chemistry, University of Rome “La Sapienza” , 1-00185 Rome, and Institute of Structural Chemistry, CNR, 1-00016 Monterotondo Stazione, Italy
| | - Clara Marciante
- Department of Chemistry, University of Rome “La Sapienza” , 1-00185 Rome, and Institute of Structural Chemistry, CNR, 1-00016 Monterotondo Stazione, Italy
| | - Gustavo Portalone
- Department of Chemistry, University of Rome “La Sapienza” , 1-00185 Rome, and Institute of Structural Chemistry, CNR, 1-00016 Monterotondo Stazione, Italy
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Abstract
Abstract
A new X-ray diffraction study of p-nitroaniline shows that through-conjugation has highly significant effects on the geometry of the molecule, as compared to aniline and p-nitrobenzoic acid. The effects include a moderate decrease of the internal angles of the ring at substituted carbons, with respect to values derived by superimposing independent angular distortions from each substituent.
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Affiliation(s)
- Marcello Colapietro
- Istituto di Strutturistica Chimica del CNR, 1-00016 Monterotondo Stazione; and Dipartimento di Chimica, Universitä di Roma, 1-00185 Roma, Italy
| | - Aldo Domenicano
- Istituto di Strutturistica Chimica del CNR, 1-00016 Monterotondo Stazione; and Dipartimento di Chimica, Universitä di Roma, 1-00185 Roma, Italy
| | - Clara Marciante
- Istituto di Strutturistica Chimica del CNR, 1-00016 Monterotondo Stazione; and Dipartimento di Chimica, Universitä di Roma, 1-00185 Roma, Italy
| | - Gustavo Portalone
- Istituto di Strutturistica Chimica del CNR, 1-00016 Monterotondo Stazione; and Dipartimento di Chimica, Universitä di Roma, 1-00185 Roma, Italy
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Brunvoll J, Colapietro M, Domenicano A, Marciante C, Portalone G, Hargittai I. Molecular Structures of p-Methylsulphonylbenzoic Acid and Methylphenylsulphone: Comparison of X-Ray and Electron Diffraction Results. Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-1984-0512] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The molecular structures of p-methylsulphonylbenzoic acid and methylphenylsulphone have been accurately determined by X-ray crystallography and gas electron diffraction, respectively. After correction for systematic effects, the geometry of the crystal molecule is seen to agree with that of the free molecule within a few thousandths of an Å unit for bond distances and a few tenths of a degree for bond angles. An exception is the S-Me bond distance, which is ca. 0.02 Å shorter in the crystal. The distortion of the benzene ring angles from 120°, an effect of the - SO2Me substituent, is virtually the same from both experiments
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Affiliation(s)
- Jon Brunvoll
- Department of Physical Chemistry, University of Trondheim , N-7000 Trondheim, Norway
| | - Marcello Colapietro
- Institute of Structural Chemistry, CNR, I-00016 Monterotondo Stazione; and Department of Chemistry, University of Rome ‘La Sapienza’, I-00185 Rome, Italy
| | - Aldo Domenicano
- Institute of Structural Chemistry, CNR, I-00016 Monterotondo Stazione; and Department of Chemistry, University of Rome ‘La Sapienza’, I-00185 Rome, Italy
| | - Clara Marciante
- Institute of Structural Chemistry, CNR, I-00016 Monterotondo Stazione; and Department of Chemistry, University of Rome ‘La Sapienza’, I-00185 Rome, Italy
| | - Gustavo Portalone
- Institute of Structural Chemistry, CNR, I-00016 Monterotondo Stazione; and Department of Chemistry, University of Rome ‘La Sapienza’, I-00185 Rome, Italy
| | - István Hargittai
- Hungarian Academy of Sciences, Research Laboratory for Inorganic Chemistry, Department of Structural Studies, Pf. 117, H-1431 Budapest, Hungary
- Visiting Professor of Chemistry and Physics for the 1983—84 academic year: Department of Physics, The University of Connecticut, Storrs, CT 06268, USA
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Portalone G. Supramolecular association in proton-transfer adducts containing benzamidinium cations. III. Three molecular salts of 3-methoxy-, 4-methoxy- and 3,4,5-trimethoxybenzoates with benzamidine. Acta Crystallogr C 2014; 70:225-9. [PMID: 24508975 DOI: 10.1107/s2053229614001090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 01/15/2014] [Indexed: 11/10/2022] Open
Abstract
Three molecular salts, benzamidinium 3-methoxybenzoate, C7H9N2(+)·C8H7O3(-), (I), benzamidinium 4-methoxybenzoate, C7H9N2(+)·C8H7O3(-), (II), and benzamidinium 3,4,5-trimethoxybenzoate monohydrate, C7H9N2(+)·C10H11O5(-)·H2O, (III), were formed from the proton-transfer reactions of 3-methoxy, 4-methoxy- and 3,4,5-trimethoxybenzoic acids with benzamidine (benzenecarboximidamide, benzam). Monoclinic salts (I) and (II) have a 1:1 ratio of cation to anion. In monoclinic salt (III), two cation-anion pairs and two water molecules constitute the asymmetric unit. In all three molecular salts, the amidinium fragments and the carboxylate groups are completely delocalized, and the delocalization favours the aggregation of the molecular components into nonplanar dimers with an R(2)(2)(8) graph-set motif by N(+)-H···O(-) (±) charge-assisted hydrogen bonding (CAHB). Of the three molecular salts, (I) and (II) show similar conformations of the anionic components and exhibit bidimensional isostructurality, which consists of alternating R(2)(2)(8) and R(6)(4)(16) rings resulting in a corrugated sheet propagated parallel to the crystallographic ab plane. In molecular salt (III), the R(2)(2)(8) synthon is retained but the supramolecular structure is different, due to the presence of three bulky methoxy substituents and a water molecule. The structures reported here further demonstrate the robustness of R(2)(2)(8) hydrogen-bonded synthons having the benzamidinium cation as a building block, whereas N(+)-H···O(-) hydrogen bonds external to the salt bridge contribute to the overall structure organization.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, University of Rome I `La Sapienza', P.le A. Moro 5, I-00185 Rome, Italy
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Abstract
The title molecular salt, C7H9N2+.C8H7O3−, was synthesized by reaction between benzamidine (benzenecarboximidamide) and 2-methoxybenzoic acid. In the cation, the amidinium group has two similar C—N bonds [1.3070 (17) and 1.3145 (16) Å] and is almost coplanar with the benzene ring, making a dihedral angle of 5.34 (12)°. In the anion, the methoxy substituent forces the carboxylate group to be twisted by 69.45 (6)° with respect to the plane of the aromatic fragment. In the crystal, the components are connected by two N+—H⋯O− (±)CAHB (charge-assisted hydrogen bonds), forming centrosymmetric ionic dimers with graph-set motif R22(8). These ionic dimers are then joined in ribbons running along the b-axis direction by another R42(8) motif involving the remaining N+—H⋯O− hydrogen bonds. Remarkably, at variance with the well known carboxylic dimer R22(8) motif, the carboxylate–amidinium pair is not planar, the dihedral angle between the planes defined by the CN2+ and CO2− atoms being 18.57 (12)°.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Affiliation(s)
- Ilaria Giannicchi
- Department of Chemistry, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
- IMC-CNR, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Gustavo Portalone
- Department of Chemistry, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Antonella Dalla Cort
- Department of Chemistry, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
- IMC-CNR, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
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Abstract
The title compound, C4H6N3O+·C5H3N2O4−·2H2O or Cyt+·Or−·2H2O, was synthesized by a reaction between cytosine (4-amino-2-hydroxypyrimidine, Cyt) and orotic acid (2,4-dihydroxy-6-carboxypyrimidine, Or) in aqueous solution. The two ions are joined by two N+—H⋯O− (±)-(CAHB) hydrogen bonds, forming a dimer with graph-set motif R22(8). In the crystal, the ion pairs of the asymmetric unit are joined by four N—H⋯O interactions to adjacent dimers, forming hydrogen-bonded rings with R22(8) graph-set motif in a two-dimensional network. The formation of the three-dimensional array is facilitated by water molecules, which act as bridges between structural sub-units linked in R32(8) and R32(7) hydrogen-bonded rings. The orotate anion is essentially planar, as the dihedral angle between the planes defined by the carboxylate group and the uracil fragment is 4.0 (4)°.
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Abstract
The title salt, C8H11N2O+·Br−, was synthesized by the reaction between 4-methoxybenzamidine (4-amidinoanisole) and hydrobromic acid. In the cation, the amidinium group has two similar C—N bonds [1.304 (2) and 1.316 (2) Å], and its plane forms a dihedral angle of 31.08 (5)° with the benzene ring. The ions are associated in the crystal into a three-dimension hydrogen-bonded supramolecular network featuring N—H+⋯Br− interactions.
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Abstract
The title salt, C8H11N2O+·NO3−, was synthesized by a reaction between 4-methoxybenzamidine (4-amidinoanisole) and nitric acid. The asymmetric unit comprises a non-planar 4-methoxybenzamidinium cation and a nitrate anion. In the cation, the amidinium group has two similar C—N bond lengths [1.302 (3) and 1.313 (3) Å] and its plane forms a dihedral angle of 32.66 (5)° with the mean plane of the benzene ring. The nitrate–amidinium ion pair is not planar, as the dihedral angle between the planes defined by the CN2+ and NO3− units is 19.28 (6)°. The ionic components are associated in the crystal via N—H⋯O hydrogen bonds, resulting in a three-dimensional network.
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Abstract
The title compound, C8H11N2O(+)·CH3CO2(-), was synthesized by a reaction between 4-meth-oxy-benzamidine (4-amidino-anisole) and acetic acid. In the cation, the amidinium group forms a dihedral angle of 11.65 (17)° with the mean plane of the benzene ring. The ionic components are associated in the crystal via N-H(+)⋯O(-) hydrogen bonds, resulting in a one-dimensional structure consisting of dimers and catemers and orientated approximately along the c axis.
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Affiliation(s)
- Simona Irrera
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Irrera S, Portalone G. 4-Meth-oxy-benzamidinium hydrogen oxalate monohydrate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o3350-1. [PMID: 23476187 PMCID: PMC3588951 DOI: 10.1107/s1600536812046351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 11/09/2012] [Indexed: 11/29/2022]
Abstract
The title hydrated salt, C8H11N2O+·C2HO4−·H2O, was synthesized by a reaction of 4-methoxybenzamidine (4-amidinoanisole) and oxalic acid in water solution. In the cation, the amidinium group forms a dihedral angle of 15.60 (6)° with the mean plane of the benzene ring. In the crystal, each amidinium unit is bound to three acetate anions and one water molecule by six distinct N—H⋯O hydrogen bonds. The ion pairs of the asymmetric unit are joined by two N—H⋯O hydrogen bonds into ionic dimers in which the carbonyl O atom of the semi-oxalate anion acts as a bifurcated acceptor, thus generating an R12(6) motif. These subunits are then joined through the remaining N—H⋯O hydrogen bonds to adjacent semi-oxalate anions into linear tetrameric chains running approximately along the b axis. The structure is stabilized by N—H⋯O and O—H⋯O intermolecular hydrogen bonds. The water molecule plays an important role in the cohesion and the stability of the crystal structure being involved in three hydrogen bonds connecting two semi-oxalate anions as donor and a benzamidinium cation as acceptor.
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Affiliation(s)
- Simona Irrera
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Irrera S, Ortaggi G, Portalone G. Supramolecular association in proton-transfer adducts containing benzamidinium cations. II. Concomitant polymorphs of the molecular salt of 2,6-dimethoxybenzoic acid with benzamidine. Acta Crystallogr C 2012; 68:o447-51. [PMID: 23124460 DOI: 10.1107/s010827011204067x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Accepted: 09/26/2012] [Indexed: 11/10/2022] Open
Abstract
Two concomitant polymorphs of the molecular salt formed by 2,6-dimethoxybenzoic acid, C(9)H(10)O(4) (Dmb), with benzamidine, C(7)H(8)N(2) (benzenecarboximidamide, Benzam) from water solution have been identified. Benzamidinidium 2,6-dimethoxybenzoate, C(7)H(9)N(2)(+)·C(9)H(9)O(4)(-) (BenzamH(+)·Dmb(-)), was obtained through protonation at the imino N atom of Benzam as a result of proton transfer from the acidic hydroxy group of Dmb. In the monoclinic polymorph, (I) (space group P2(1)/n), the asymmetric unit consists of two Dmb(-) anions and two monoprotonated BenzamH(+) cations. In the orthorhombic polymorph, (II) (space group P2(1)2(1)2(1)), one Dmb(-) anion and one BenzamH(+) cation constitute the asymmetric unit. In both polymorphic salts, the amidinium fragments and carboxylate groups are completely delocalized. This delocalization favours the aggregation of the molecular components of these acid-base complexes into nonplanar dimers with an R(2)(2)(8) graph-set motif via N(+)-H···O(-) charge-assisted hydrogen bonding. Both the monoclinic and orthorhombic forms exhibit one-dimensional isostructurality, as the crystal structures feature identical hydrogen-bonding motifs consisting of dimers and catemers.
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Affiliation(s)
- Simona Irrera
- Chemistry Department, University of Rome I `La Sapienza', P. le A. Moro 5, I-00185 Rome, Italy
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Abstract
In the cation of the title compound, C(8)H(11)N(2)O(+)·Cl(-)·H(2)O, the C-N bonds of the amidinium group are identical within experiemental error [1.305 (2) and 1.304 (2) Å], and its plane forms a dihedral angle of 25.83 (8)° with the phenyl ring. The ionic components are associated in the crystal into polymeric hydrogen-bonded supra-molecular tapes stabilized by N-H(+)⋯Cl(-) and N-H(+)⋯Ow inter-molecular hydrogen bonds, and by Ow-H⋯Cl(-) inter-actions.
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Affiliation(s)
- Simona Irrera
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Abstract
The title salt, C8H11N2O+·HSO4−, has been synthesized by the reaction between 4-methoxybenzamidine and sulfuric acid. The asymmetric unit comprises a nonplanar 4-methoxybenzamidinium cation and one hydrogen sulfate anion. In the cation, the amidinium group has two identical C—N bonds [1.306 (2) and 1.308 (2) Å], and its plane forms a dihedral angle of 6.49 (8)° with the mean plane of the benzene ring. The ionic components are associated in the crystal via N—H+⋯O−, resulting in chains running approximately along the b-axis direction whicg are interconnected by O—H⋯O− hydrogen bonds.
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Affiliation(s)
- Simona Irrera
- Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
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Abstract
The title compound, C8H11N2O+·C9H9O4−, was synthesized by the reaction of 4-methoxybenzamidine (4-amidinoanisole) and 2,6-dimethoxybenzoic acid. The structure consists of non-planar pairs of hydrogen-bonded 4-methoxybenzamidinium cations and 2,6-dimethoxybenzoate anions. In the cation, the amidinium group is tilted by 27.94 (10)° with respect to the benzene ring. In the anion, the sterically bulky ortho-methoxy substituents force the carboxyate group to be twisted away from the plane of the benzene ring by 73.24 (6)°. The ions are further associated in the crystal into chains along the b-axis direction by intermolecular N—H⋯O hydrogen bonds.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Lombardo GM, Portalone G, Chiacchio U, Rescifina A, Punzo F. Potassium caffeate/caffeic acid co-crystal: the rat race between the catecholic and carboxylic moieties in an atypical co-crystal. Dalton Trans 2012; 41:14337-44. [DOI: 10.1039/c2dt31092a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
A new crystalline form of 2,6-dimethoxybenzoic acid, C9H10O4, crystallizing in a tetragonal unit cell has been identified during screening for co-crystals. The asymmetric unit comprises a non-planar independent molecule with a synplanar conformation of the carboxy group. The sterically bulky o-methoxy substituents force the carboxy group to be twisted away from the plane of the benzene ring by 65.72 (15)°. The carboxy group is disordered over two sites about the C—C bond [as indicated by the almost equal C—O distances of 1.254 (3) and 1.250 (3) Å], the occupancies of the disordered carboxym H atoms being 0.53 (5) and 0.47 (5). In the known orthorhombic form reported by Swaminathan et al. [Acta Cryst. (1976), B32, 1897–1900], due to the antiplanar conformation adopted by the OH group, the molecular components are associated in the crystal in chains stabilized by linear O—H⋯O hydrogen bonds. However, in the new tetragonal polymorph, molecules form dimeric units via pairs of O—H⋯O hydrogen bonds between the carboxy groups.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Portalone G. Solid-phase molecular recognition of cytosine based on proton-transfer reaction. Part II. supramolecular architecture in the cocrystals of cytosine and its 5-Fluoroderivative with 5-Nitrouracil. Chem Cent J 2011; 5:51. [PMID: 21888640 PMCID: PMC3182958 DOI: 10.1186/1752-153x-5-51] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 09/02/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cytosine is a biologically important compound owing to its natural occurrence as a component of nucleic acids. Cytosine plays a crucial role in DNA/RNA base pairing, through several hydrogen-bonding patterns, and controls the essential features of life as it is involved in genetic codon of 17 amino acids. The molecular recognition among cytosines, and the molecular heterosynthons of molecular salts fabricated through proton-transfer reactions, might be used to investigate the theoretical sites of cytosine-specific DNA-binding proteins and the design for molecular imprint. RESULTS Reaction of cytosine (Cyt) and 5-fluorocytosine (5Fcyt) with 5-nitrouracil (Nit) in aqueous solution yielded two new products, which have been characterized by single-crystal X-ray diffraction. The products include a dihydrated molecular salt (CytNit) having both ionic and neutral hydrogen-bonded species, and a dihydrated cocrystal of neutral species (5FcytNit). In CytNit a protonated and an unprotonated cytosine form a triply hydrogen-bonded aggregate in a self-recognition ion-pair complex, and this dimer is then hydrogen bonded to one neutral and one anionic 5-nitrouracil molecule. In 5FcytNit the two neutral nucleobase derivatives are hydrogen bonded in pairs. In both structures conventional N-H...O, O-H...O, N-H+...N and N-H...N- intermolecular interactions are most significant in the structural assembly. CONCLUSION The supramolecular structure of the molecular adducts formed by cytosine and 5-fluorocytosine with 5-nitrouracil, CytNit and 5FcytNit, respectively, have been investigated in detail. CytNit and 5FcytNit exhibit widely differing hydrogen-bonding patterns, though both possess layered structures. The crystal structures of CytNit (Dpka = -0.7, molecular salt) and 5FcytNit (Dpka = -2.0, cocrystal) confirm that, at the present level of knowledge about the nature of proton-transfer process, there is not a strict correlation between the Dpka values and the proton transfer, in that the acid/base pka strength is not a definite guide to predict the location of H atoms in the solid state. Eventually, the absence in 5FcytNit of hydrogen bonds involving fluorine is in agreement with findings that covalently bound fluorine hardly ever acts as acceptor for available Brønsted acidic sites in the presence of competing heteroatom acceptors.
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Affiliation(s)
- Gustavo Portalone
- Department of Chemistry, "Sapienza" University of Rome, P,le A, Moro 5, Rome I-00185, Italy.
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Habgood M, Price SL, Portalone G, Irrera S. Testing a Variety of Electronic-Structure-Based Methods for the Relative Energies of 5-Formyluracil Crystals. J Chem Theory Comput 2011; 7:2685-8. [PMID: 26605460 DOI: 10.1021/ct200354t] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The lattice energies of the experimental and several hypothetical crystal structures of the RNA base uracil derivative 5-formyluracil are calculated with a range of methods, based either on the electronic structure of the molecule or the lattice. The explicit modeling of the polarization within the crystal in the model intermolecular potential and the inclusion of an empirical dispersion correction to the periodic density functional energy (DFT-D2) were the only methods able to calculate the energy balance between different conformations, hydrogen bonding, and π-π stacking possibilities sufficiently accurately to give the observed structure as the most stable. Even these two methods underestimated the density of the room temperature structure, showing the need for improvement in the modeling of organic crystal structures.
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Affiliation(s)
- Matthew Habgood
- Department of Chemistry, University College London , 20 Gordon Street, London, WC1H 0AJ United Kingdom
| | - Sarah L Price
- Department of Chemistry, University College London , 20 Gordon Street, London, WC1H 0AJ United Kingdom
| | - Gustavo Portalone
- Dipartimento di Chimica, "Sapienza" Università di Roma, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Simona Irrera
- Department of Chemistry, University College London , 20 Gordon Street, London, WC1H 0AJ United Kingdom
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Portalone G, Irrera S. Supramolecular structure of unnatural nucleobases: Revised structure of (2:1) 6-methylisocytosinium dihydrogen monophosphate adduct. J Mol Struct 2011. [DOI: 10.1016/j.molstruc.2011.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Bauer EM, Bellitto C, Imperatori P, Righini G, Colapietro M, Portalone G, Gómez-García CJ. A Novel 1D-AF Hybrid Organic−Inorganic Chromium(II) Methyl Phosphonate Dihydrate: Synthesis, X-Ray Crystal and Molecular Structure, and Magnetic Properties. Inorg Chem 2010; 49:7472-7. [DOI: 10.1021/ic1009362] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elvira M. Bauer
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Via Salaria km 29.300, P.O. Box 10, 00015 Monterotondo (RM), Italy
| | - Carlo Bellitto
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Via Salaria km 29.300, P.O. Box 10, 00015 Monterotondo (RM), Italy
| | - Patrizia Imperatori
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Via Salaria km 29.300, P.O. Box 10, 00015 Monterotondo (RM), Italy
| | - Guido Righini
- Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, Via Salaria km 29.300, P.O. Box 10, 00015 Monterotondo (RM), Italy
| | - Marcello Colapietro
- Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Roma, Italy
| | - Gustavo Portalone
- Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Roma, Italy
| | - Carlos J. Gómez-García
- Instituto de Ciencia Molecular (ICMol), Parque Científico, Universidad de Valencia, 46980 Paterna, Valencia, Spain
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Torino D, Mollica A, Pinnen F, Feliciani F, Lucente G, Fabrizi G, Portalone G, Davis P, Lai J, Ma SW, Porreca F, Hruby VJ. Synthesis and evaluation of new endomorphin-2 analogues containing (Z)-alpha,beta-didehydrophenylalanine (Delta(Z)Phe) residues. J Med Chem 2010; 53:4550-4. [PMID: 20476738 DOI: 10.1021/jm1001343] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
New endomorphin-2 (EM-2) analogues incorporating (Z)-alpha,beta-didehydrophenylalanine (Delta(Z)Phe) in place of the native phenylalanine in EM-2 are reported. Tyr-Pro-Delta(Z)Phe-Phe-NH(2) {[Delta(Z)Phe(3)]EM-2} (1), Tyr-Pro-Phe-Delta(Z)Phe-NH(2) {[Delta(Z)Phe(4)]EM-2} (2), and Tyr-Pro-Delta(Z)Phe-Delta(Z)Phe-NH(2) {[Delta(Z)Phe(3,4)]EM-2}(3) have been synthesized, their opioid receptor binding affinities and tissue bioassay activities were determined, and their conformational properties were examined. Compound 2 shows high mu opioid receptor selectivity and mu agonist activity comparable to those of the native peptide. The conformation adopted in solution and in the crystal by N-Boc-Tyr-Pro-Delta(Z)Phe-Phe-NH(2) (8) is reported.
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Affiliation(s)
- Domenica Torino
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza, Università di Roma, P.le A.Moro, 00185 Roma, Italy
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Portalone G. Supramolecular association in proton-transfer adducts containing benzamidinium cations. I. Four molecular salts with uracil derivatives. Acta Crystallogr C 2010; 66:o295-301. [PMID: 20522949 DOI: 10.1107/s0108270110016252] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 05/03/2010] [Indexed: 11/10/2022] Open
Abstract
Four organic salts, namely benzamidinidium orotate (2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylate) hemihydrate, C(7)H(9)N(2)(+).C(5)H(3)N(2)O(4)(-).0.5H(2)O (BenzamH(+).Or(-)), (I), benzamidinium isoorotate (2,4-dioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate) trihydrate, C(7)H(9)N(2)(+).C(5)H(3)N(2)O(4)(-).3H(2)O (BenzamH(+).Isor(-)), (II), benzamidinium diliturate (5-nitro-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate) dihydrate, C(7)H(9)N(2)(+).C(4)H(2)N(3)O(5)(-).2H(2)O (BenzamH(+).Dil(-)), (III), and benzamidinium 5-nitrouracilate (5-nitro-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ide), C(7)H(9)N(2)(+).C(4)H(2)N(3)O(4)(-) (BenzamH(+).Nit(-)), (IV), have been synthesized by a reaction between benzamidine (benzenecarboximidamide or Benzam) and the appropriate carboxylic acid. Proton transfer occurs to the benzamidine imino N atom. In all four acid-base adducts, the asymmetric unit consists of one tautomeric aminooxo anion (Or(-), Isor(-), Dil(-) and Nit(-)) and one monoprotonated benzamidinium cation (BenzamH(+)), plus one-half (which lies across a twofold axis), three and two solvent water molecules in (I), (II) and (III), respectively. Due to the presence of protonated benzamidine, these acid-base complexes form supramolecular synthons characterized by N(+)-H...O(-) and N(+)-H...N(-) (+/-)-charge-assisted hydrogen bonds (CAHB).
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, Sapienza University of Rome, Piazzale A. Moro 5, I-00185 Rome, Italy.
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Abstract
The crystal structure of the title compound, C7H5NO4, was first reported by Kurahashi, Fukuyo & Shimada [(1967). Bull. Chem. Soc. Jpn, 40, 1296]. It has been re-examined, improving the precision of the derived geometric parameters. The asymmetric unit comprises a non-planar independent molecule, as the nitro and the carboxy substituents force each other to be twisted away from the plane of the aromatic ring by 54.9 (2) and 24.0 (2)°, respectively. The molecules form a conventional dimeric unit via centrosymmetric intermolecular hydrogen bonds.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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Viola E, Donzello MP, Ciattini S, Portalone G, Ercolani C. Redox Chemistry of Tetrakis[5,6-di(2-pyridyl)-2,3-pyrazino]porphyrazinatocobalt(II): Isolation and Characterization of Solid Pure CoI, CoII, and CoIIIComplexes. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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38
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Abstract
The crystal structure of the title compound, C9H10O4, was first reported by Swaminathan, Vimala & Lotter [Acta Cryst. (1976), B32, 1897–1900]. It has been re-examined, improving the precision of the derived geometric parameters. The asymmetric unit comprises a non-planar independent molecule, as the methoxy substituents force the carboxy group to be twisted away from the plane of the aromatic ring by 56.12 (9)°. Due to the antiplanar conformation adopted by the OH group, the molecular components do not form the conventional dimeric units, but are associated in the crystal in chains stabilized by linear O—H⋯O hydrogen bonds, involving the OH groups and the carbonyl O atoms, which form C(3) motifs.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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39
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Bauer EM, Bellitto C, Righini G, Colapietro M, Portalone G, Drillon M, Rabu P. Comparison of the Structure and Magnetic Order in a Series of Layered Ni(II) Organophosphonates, Ni[(RPO3)(H2O)] (R = C6H5, CH3, C18H37). Inorg Chem 2008; 47:10945-52. [DOI: 10.1021/ic801124z] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elvira M. Bauer
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Carlo Bellitto
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Guido Righini
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Marcello Colapietro
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Gustavo Portalone
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Marc Drillon
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
| | - Pierre Rabu
- CNR-Istituto di Struttura della Materia, Via Salaria Km. 29.3, I-00016 Monterotondo Stazione, Rome, Italy, Department of Chemistry, University of Rome “Sapienza”, P.le A. Moro 5, 00185 Rome, Italy, and Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504 CNRS - ULP, 23 rue du Loess, 67034 Strasbourg, France
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40
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Abstract
The structure of acetoguanamine (or 2,4-diamino-6-methyl-1,3,5-triazine) has been determined as the N,N-dimethyl-formamide solvate, C(4)H(7)N(5)·C(3)H(7)NO. The mol-ecular components are associated in the crystal structure to form ribbons stabilized by three N-H⋯N and one N-H⋯O hydrogen bonds which involve NH groups as donors and the N atoms of the heterocyclic ring and the carbonyl O atom of the solvent as acceptors.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
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41
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Abstract
The asymmetric unit of the title compound [systematic name: benzamidinium 3,3′,5,5′-tetrahydroxy-1,1′-spirobi[2,4,6-trioxa-1,3,5-triboracyclohexane](1−) sesquihydrate], C7H9N2+·B5H4O10−·1.5H2O, is composed of two protonated benzamidinium cations, two tetrahydropentaborate anions and three water molecules of crystallization. The ions and water molecules are associated in the crystal structure by an extensive three-dimensional hydrogen-bonding network, which consists mainly of cation-to-anion N—H⋯O and anion-to-anion O—H⋯O hydrogen bonds.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, University of Rome "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy
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42
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Abstract
The crystal structure of the title compound, 4-hydroxy-2-pyridone, C5H5NO2, which has been the subject of several determinations using X-rays and neutron diffraction, was first reported by Low & Wilson [Acta Cryst. (1983). C39, 1688–1690]. It has been redetermined, providing a significant increase in the precision of the derived geometric parameters. The asymmetric unit comprises a planar 4-enol tautomer having some degree of delocalization of π-electron density through the molecule. In the crystal structure, the molecules are connected into chains by two strong O—H⋯O and N—H⋯O hydrogen bonds between the OH and NH groups and the carbonyl O atom.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy
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43
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Portalone G, Cassetta A, Colapietro M, Plattner SH. (3 R,5 S)-5(3)-Carboxy-3,4,5,6-tetrahydro-2 H-1,4-thiazin-4-ium-3(5)-carboxylate. Acta Crystallogr Sect E Struct Rep Online 2008; 64:o636. [PMID: 21201967 PMCID: PMC2960813 DOI: 10.1107/s1600536808005151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Accepted: 02/22/2008] [Indexed: 11/10/2022]
Abstract
The molecule of the zwitterionic title compound, C6H9NO4S, which lies on a mirror plane, shows a puckered chair conformation of the six-membered ring with the S and N atoms out of the mean plane of the other four C atoms by 0.929 (2) and 0.647 (2) Å, respectively. The ionized carboxyl group is equatorially oriented. The hydrogen-bonding network includes very short O—H⋯O [2.470 (2) Å] and N—H⋯S [3.471 (2) and 3.416 (2) Å] intermolecular contacts.
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Abstract
The asymmetric unit of the title compound, C(2)H(9)N(5) (2+)·2Cl(-), is composed of one diprotonated biguanidinium cation and two chloride anions. The diprotonated cation consists of two planar halves twisted by 36.42 (6)°. The ions are associated in the crystal structure by extensive hydrogen bonding into a three-dimensional network; the diprotonated biguanidinium cation is hydrogen bonded to the chloride anions.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
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45
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Abstract
The crystal structure of the title compound, which is also known as vitamin B(13) (systematic name: 2,6-dioxo-1,2,3,6-tetra-hydro-pyrimidine-4-carboxylic acid monohydrate), C(5)H(4)N(2)O(4)·H(2)O, was reported for the first time by Takusagawa & Shimada [Bull. Chem. Soc. Jpn (1973 ▶), 46, 2011-2019]. The present redetermination provides more precise values of the mol-ecular geometry. The asymmetric unit comprises a planar diketo tautomer and a solvent water mol-ecule. In the crystal structure, mol-ecules are connected by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds involving NH groups, two carbonyl O atoms and the solvent water mol-ecule.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro 5, I-00185 Rome, Italy
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46
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Abstract
The title compound (systematic name: 2,4-dihydroxy-5-iodopyrimidine), C4H3IN2O2, which was first reported by Sternglanz, Freeman & Bugg [Acta Cryst. (1975 ▶), B31, 1393–1395], has been redetermined, providing a significant increase in the precision of the derived geometric parameters. The asymmetric unit comprises a non-planar molecule in a slightly distorted B25 boat conformation. The molecules are associated in the crystal structure to form ribbons stabilized by N—H⋯O hydrogen bonds which involve NH groups and two carbonyl O atoms.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
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47
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Abstract
In the title compound (alternative name: pyridine-3-carbohydrazide, C6H7N3O), the asymmetric unit contains a single molecule. In contrast with nicotinic acid and nicotinamide, the C=O bond is found to be oriented cis with respect to the Cipso C N fragment in the pyridine ring. The pyridine ring and the hydrazide group make a dihedral angle of 34.0 (2)°. In the crystal structure, molecules are associated into a three-dimensional framework by a combination of N—H⋯N and three-centre N—H⋯O hydrogen bonds.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
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48
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Portalone G, Colapietro M. Hydrogen-bonded supramolecular motifs in the 1:1 monohydrated molecular adduct of acetoguanaminium chloride with acetoguanamine and in 2,4,6-triaminopyrimidinediium dichloride dihydrate. Acta Crystallogr C 2007; 63:o655-8. [PMID: 17989489 DOI: 10.1107/s0108270107046689] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2007] [Accepted: 09/22/2007] [Indexed: 11/10/2022] Open
Abstract
In the 1:1 monohydrated molecular adduct 2,4-diamino-6-methyl-1,3,5-triazin-1-ium chloride 2,4-diamino-6-methyl-1,3,5-triazine monohydrate, C(4)H(8)N(5)(+).Cl(-).C(4)H(7)N(5).H(2)O, formed between 2,4-diamino-6-methyl-1,3,5-triazin-1-ium chloride (acetoguanaminium chloride) and 2,4-diamino-6-methyl-1,3,5-triazine (acetoguanamine), and in triaminopyrimidinediium dichloride dihydrate, C(4)H(9)N(5)(2+).2Cl(-).2H(2)O, whose cationic component lies across a twofold rotation axis, the protonation occurs at the ring N atoms and the bond distances in the protonated molecules indicate significant bond alterations, consistent with charge-separated polar forms. The supramolecular structures of both compounds are stabilized by systems of hydrogen bonds forming complex sheets, interlinked by sets of hydrogen bonds involving the solvent water molecules and the chloride anions.
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Affiliation(s)
- Gustavo Portalone
- Chemistry Department, University of Rome I La Sapienza, Piazzale Aldo Moro 5, I-00185 Rome, Italy.
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49
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Portalone G, Colapietro M. An unusualsynconformation of 5-formyluracil stabilized by supramolecular interactions. Acta Crystallogr C 2007; 63:o650-4. [DOI: 10.1107/s0108270107045659] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 09/17/2007] [Indexed: 05/25/2023] Open
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50
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Cametti M, Dalla Cort A, Colapietro M, Portalone G, Russo L, Rissanen K. Evidence of the Facile Hydride and Enolate Addition to the Imine Bond of an Aluminum−Salophen Complex. Inorg Chem 2007; 46:9057-9. [PMID: 17892286 DOI: 10.1021/ic701521s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The isolation of complexes 2 and 3, unambiguously characterized by single-crystal X-ray diffraction, demonstrates that nucleophilic additions to the aluminum-coordinated imino bond of salophen complex 1 can be achieved under very mild conditions.
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Affiliation(s)
- Massimo Cametti
- Dipartimento di Chimica and IMC-Consiglio Nazionale delle Ricerche, Università La Sapienza, Rome, Italy
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