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Majhi D, Stevensson B, Nguyen TM, Edén M. 1H and 13C chemical shift-structure effects in anhydrous β-caffeine and four caffeine-diacid cocrystals probed by solid-state NMR experiments and DFT calculations. Phys Chem Chem Phys 2024; 26:14345-14363. [PMID: 38700003 DOI: 10.1039/d3cp06197c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
By using density functional theory (DFT) calculations, we refined the H atom positions in the structures of β-caffeine (C), α-oxalic acid (OA; (COOH)2), α-(COOH)2·2H2O, β-malonic acid (MA), β-glutaric acid (GA), and I-maleic acid (ME), along with their corresponding cocrystals of 2 : 1 (2C-OA, 2C-MA) or 1 : 1 (C-GA, C-ME) stoichiometry. The corresponding 13C/1H chemical shifts obtained by gauge including projector augmented wave (GIPAW) calculations agreed overall very well with results from magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy experiments. Chemical-shift/structure trends of the precursors and cocrystals were examined, where good linear correlations resulted for all COO1H sites against the H⋯O and/or H⋯N H-bond distance, whereas a general correlation was neither found for the aliphatic/caffeine-stemming 1H sites nor any 13C chemical shift against either the intermolecular hydrogen- or tetrel-bond distance, except for the 13COOH sites of the 2C-OA, 2C-MA, and C-GA cocrystals, which are involved in a strong COOH⋯N bond with caffeine that is responsible for the main supramolecular stabilization of the cocrystal. We provide the first complete 13C NMR spectral assignment of the structurally disordered anhydrous β-caffeine polymorph. The results are discussed in relation to previous literature on the disordered α-caffeine polymorph and the ordered hydrated counterpart, along with recommendations for NMR experimentation that will secure sufficient 13C signal-resolution for reliable resonance/site assignments.
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Affiliation(s)
- Debashis Majhi
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden.
| | - Baltzar Stevensson
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden.
| | - Tra Mi Nguyen
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden.
| | - Mattias Edén
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden.
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2
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Hareendran C, Alsirawan B, Paradkar A, Ajithkumar TG. In Situ Monitoring of Competitive Coformer Exchange Reaction by 1H MAS Solid-State NMR. Mol Pharm 2024; 21:1479-1489. [PMID: 38373877 DOI: 10.1021/acs.molpharmaceut.3c01118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
In a competitive coformer exchange reaction, a recent topic of interest in pharmaceutical research, the coformer in a pharmaceutical cocrystal is exchanged with another coformer that is expected to form a cocrystal that is more stable. There will be a competition between coformers to form the most stable product through the formation of hydrogen bonds. This will cause destabilization of the pharmaceutical products during processing or storage. Therefore, it is important to develop a mechanistic understanding of this transformation by monitoring each and every step of the reaction, employing a technique such as 1H nuclear magnetic resonance (NMR). In this study, an in situ monitoring of a coformer exchange reaction is carried out by 1H magic angle spinning (MAS) solid-state NMR (SSNMR) at a spinning frequency of 60 kHz. The changes in caffeine maleic acid cocrystals on addition of glutaric acid and caffeine glutaric cocrystals on addition of maleic acid were monitored. In all of the reactions, it has been observed that caffeine glutaric acid Form I is formed. When glutaric acid was added to 2:1 caffeine maleic acid, the formation of metastable 1:1 caffeine glutaric acid Form I was observed at the start of the experiment, indicating that the centrifugal pressure is enough for the formation. The difference in the end product of the reactions with a similar reaction pathway of 1:1 and 2:1 reactant stoichiometry indicates that a complete replacement of maleic acid has occurred only in the 1:1 stoichiometry of the reactants. The polymorphic transition of caffeine glutaric acid Form II to Form I at higher temperatures was a crucial reason that triggered the exchange of glutaric acid with maleic acid in the reaction of caffeine glutaric acid and maleic acid. Our results are novel since the new reaction pathways in competitive coformer exchange reactions enabled understanding the remarkable role of stoichiometry, polymorphism, temperature, and centrifugal pressure.
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Affiliation(s)
- Chaithanya Hareendran
- Central NMR Facility, and Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Bashir Alsirawan
- Centre for Pharmaceutical Engineering Science, School of Pharmacy and Medical Sciences, University of Bradford, Bradford BD7 1DP, United Kingdom
| | - Anant Paradkar
- Centre for Pharmaceutical Engineering Science, School of Pharmacy and Medical Sciences, University of Bradford, Bradford BD7 1DP, United Kingdom
| | - T G Ajithkumar
- Central NMR Facility, and Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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3
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Yano Y, Ono T, Ohhara T, Hisaeda Y. Insights into Proton Dynamics in a Photofunctional Salt-Cocrystal Continuum: Single-Crystal X-ray, Neutron Diffraction, and Hirshfeld Atom Refinement. Chemistry 2021; 27:17802-17807. [PMID: 34751473 DOI: 10.1002/chem.202103044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Indexed: 11/09/2022]
Abstract
X-ray diffraction, neutron diffraction, and theoretical calculations were used to investigate the relationship between the optical properties and degree of protonation in acid-base complexes. We prepared five acid-base complexes by using a pyridine-modified pyrrolopyrrole derivative and salicylic acid. Two of the prepared acid-base complexes were polymorphs of guest-free crystals with green emission; the other three were guest-inclusion crystals with yellow emission containing CH2 Cl2 , CH2 Br2 , or C2 H4 Cl2 . The presence or absence of guests caused the emission to change color, altering the hydrogen bond strength between the acid-base complexes. Accurate N⋅⋅⋅H distances between the pyridyl moiety and the carboxy group over the temperature range 123 to 273 K were 1.40 Å for the guest-free crystals and 1.25 Å for the guest-inclusion crystals. Our findings contribute to a better understanding of the complex relationship between photofunction and proton dynamics in acid-base complexes.
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Affiliation(s)
- Yoshio Yano
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Toshikazu Ono
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Takashi Ohhara
- J-PARC Center, Japan Atomic Energy Agency Tokai, Naka-gun, 319-1195, Japan
| | - Yoshio Hisaeda
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
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4
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Jung K, Kim S, Choi S, Kim I, Han G. Development of a DABCO-Succinic Acid Based Catalytic System for the Aza-Michael Addition and Aza-Michael/Knoevenagel Tandem Reaction of Thiazolidine-2,4-dione to Electron Deficient Alkenes. J Org Chem 2021; 86:16785-16794. [PMID: 34757757 DOI: 10.1021/acs.joc.1c02003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A DABCO catalyzed aza-Michael addition of thiazolidine-2,4-dione to a variety of electron deficient alkenes has been developed. Additionally, a DABCO/succinic acid salt system has been designed that allows for the one pot tandem aza-Michael/Knoevenagel reaction of thiazolidine-2,4-dione to give difunctionalized thiazolidine-2,4-dione products. To the best of our knowledge, this is the first example of a one-pot tandem aza-Michael/Knoevenagel reaction involving thiazolidine-2,4-dione.
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Affiliation(s)
- Kilsoo Jung
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon 21983, Republic of Korea
| | - Sunmi Kim
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon 21983, Republic of Korea
| | - Seonghwi Choi
- Department of Integrated OMICS for Biomedical Sciences (WCU Program), Yonsei University, Seoul 03722, Republic of Korea
| | - Ikyon Kim
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon 21983, Republic of Korea
| | - Gyoonhee Han
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon 21983, Republic of Korea.,Department of Integrated OMICS for Biomedical Sciences (WCU Program), Yonsei University, Seoul 03722, Republic of Korea.,Department of Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
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5
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Pindelska E, Marczewska-Rak A, Jaśkowska J, Madura ID. Solvates of New Arylpiperazine Salicylamide Derivative-a Multi-Technique Approach to the Description of 5 HTR Ligand Structure and Interactions. Int J Mol Sci 2021; 22:ijms22094992. [PMID: 34066719 PMCID: PMC8125853 DOI: 10.3390/ijms22094992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/21/2022] Open
Abstract
A new ligand for 5-HT1A and 5-HT7 receptors, an arylpiperazine salicylamide derivative with an inflexible spacer, is investigated to identify preferred fragments capable of creating essential intermolecular interactions in different solvates. To fully identify and characterize the obtained crystalline materials, various methods including powder and single-crystal X-ray diffraction, solid-state NMR, and thermal analysis were employed, supplemented by periodic ab initio calculations. The molecular conformation in different solvates, types, and hierarchy of intermolecular interactions as well as the crystal packing were investigated to provide data for future research focused on studying protein–ligand interactions. Based on various methods of crystal structure analysis, including the interaction energy calculation and programs using an artificial neural network, a salicylamide fragment was found to be crucial for intermolecular contacts, mostly of dispersion and electrostatic character. A supramolecular 2D kite-type layer of {4,4} topology was found to form in crystals. The closed voids between layers contain disordered solvents, very weakly interacting with the molecule and the layer. It has been postulated that the separation of the layers might be influenced by an increase in temperature or the size of the solvent; hence, only methanol and ethanol hemi-solvates could be obtained from a series of various alcohols.
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Affiliation(s)
- Edyta Pindelska
- Department of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-093 Warsaw, Poland
- Correspondence: (E.P.); (I.D.M.)
| | - Anna Marczewska-Rak
- Scientific Circle “Spektrum” at Department of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-093 Warsaw, Poland;
| | - Jolanta Jaśkowska
- Department of Organic Chemistry and Technology, Faculty of Chemical and Engineering and Technology, Cracow University of Technology, 24 Warszawska Street, 31-155 Cracow, Poland;
| | - Izabela D. Madura
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
- Correspondence: (E.P.); (I.D.M.)
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6
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Reviglio AL, Martínez FA, Montero MDA, Garro-Linck Y, Aucar GA, Sperandeo NR, Monti GA. Accurate location of hydrogen atoms in hydrogen bonds of tizoxanide from the combination of experimental and theoretical models. RSC Adv 2021; 11:7644-7652. [PMID: 35423249 PMCID: PMC8695048 DOI: 10.1039/d0ra10609g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 02/05/2021] [Indexed: 11/25/2022] Open
Abstract
To obtain detailed information about the position of hydrogen atoms in hydrogen bonds, HBs, of crystalline organic molecular compounds is not an easy task. In this work we propose a combination of ssNMR experimental data with theoretical procedures to get such information. Furthermore, the combination of experimental and theoretical models provides us with well-defined grounds to analyse the strength of π-stacking interactions between layers of hydrogen bonded molecules. Two different theoretical models were considered, both approaches being quite different. The first one is a solid-state model, so that the periodicity of a crystalline system underlies calculations of the electronic energy, the electronic density and NMR parameters. The other one is a molecular model in which molecules are taken as isolated monomers, dimers and tetramers. These two models were applied to the tizoxanide, TIZ, molecular crystal though it can widely be applied to any other molecular crystal. By the application of the quantum molecular model it was possible to learn about the way the intermolecular HBs affect the position of hydrogen atoms that belong to HBs in TIZ. This molecule has two intermolecular HBs that stabilize the structure of a basic dimer, but it also has an intramolecular HB in each monomer whose position should be optimized together with the other ones. We found that by doing this it is possible to obtain reliable results of calculations of NMR spectroscopic parameters. Working with the solid-state model we found that any local variation of the TIZ crystalline structure is correlated with the variation of the values of the NMR parameters of each nucleus. The excellent agreement between experimental and calculated chemical shifts leads to the conclusion that the N10-H10 bond distance should be (1.00 ± 0.02) Å.
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Affiliation(s)
- Ana L Reviglio
- FAMAF, UNC Córdoba Argentina
- Instituto de Física Enrique Gaviola (IFEG), CONICET-UNC Córdoba Argentina
| | - Fernando A Martínez
- Institute of Modelling and Innovation on Technology (IMIT), CONICET-UNNE Corrientes Argentina
- Physics Department, Natural and Exact Science Faculty, Northeastern University of Argentina Corrientes Argentina
| | - Marcos D A Montero
- Institute of Modelling and Innovation on Technology (IMIT), CONICET-UNNE Corrientes Argentina
- Physics Department, Natural and Exact Science Faculty, Northeastern University of Argentina Corrientes Argentina
| | - Yamila Garro-Linck
- FAMAF, UNC Córdoba Argentina
- Instituto de Física Enrique Gaviola (IFEG), CONICET-UNC Córdoba Argentina
| | - Gustavo A Aucar
- Institute of Modelling and Innovation on Technology (IMIT), CONICET-UNNE Corrientes Argentina
- Physics Department, Natural and Exact Science Faculty, Northeastern University of Argentina Corrientes Argentina
| | - Norma R Sperandeo
- Departamento de Ciencias Farmacéuticas, FCQ, UNC Córdoba Argentina
- UNITEFA-CONICET Córdoba Argentina
| | - Gustavo A Monti
- FAMAF, UNC Córdoba Argentina
- Instituto de Física Enrique Gaviola (IFEG), CONICET-UNC Córdoba Argentina
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7
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New Pharmaceutical Salts of Trazodone. Molecules 2021; 26:molecules26030769. [PMID: 33540851 PMCID: PMC7867375 DOI: 10.3390/molecules26030769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/20/2021] [Accepted: 01/26/2021] [Indexed: 11/30/2022] Open
Abstract
New pharmaceutically acceptable salts of trazodone (trazodone hydrogen bromide and trazodone 1-hydroxy-2-naphthonic acid) for the treatment of central nervous system disorders are synthesized and described. Although trazodone salts are poorly crystalline, single-crystal X-ray diffraction data for trazodone 1-hydroxy-2-naphthonic acid were collected and analyzed as well as compared to the previously described crystal structure of commercially available trazodone hydrochloride. The powder samples of all new salts were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and 13C solid-state nuclear magnetic resonance spectroscopy. Spectroscopic studies were supported by gauge including projector augmented wave (GIPAW) calculations of carbon chemical shielding constants. The main goal of our research was to find salts with better physicochemical properties and to make an attempt to associate them with both the anion structure and the most prominent interactions exhibited by the protonated trazodone cation. The dissolution profiles of trazodone from tablets prepared from various salts with lactose monohydrate were investigated. The studies revealed that salts with simple anions show a fast release of the drug while the presence of more complex anion, more strongly interacting with the cation, effects a slow-release profile of the active substance and can be used for the preparation of the tables with a delay or prolonged mode of action.
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8
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Hodgkinson P. NMR crystallography of molecular organics. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 118-119:10-53. [PMID: 32883448 DOI: 10.1016/j.pnmrs.2020.03.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/25/2020] [Accepted: 03/13/2020] [Indexed: 06/11/2023]
Abstract
Developments of NMR methodology to characterise the structures of molecular organic structures are reviewed, concentrating on the previous decade of research in which density functional theory-based calculations of NMR parameters in periodic solids have become widespread. With a focus on demonstrating the new structural insights provided, it is shown how "NMR crystallography" has been used in a spectrum of applications from resolving ambiguities in diffraction-derived structures (such as hydrogen atom positioning) to deriving complete structures in the absence of diffraction data. As well as comprehensively reviewing applications, the different aspects of the experimental and computational techniques used in NMR crystallography are surveyed. NMR crystallography is seen to be a rapidly maturing subject area that is increasingly appreciated by the wider crystallographic community.
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Affiliation(s)
- Paul Hodgkinson
- Department of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, UK.
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9
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Fang T, Jie Y, Huang Y, Ye YH, Chen WB, Li BQ, Zou C, Xu DL, Qian K. Above Room Temperature Organic Dielectric Switchable Material: Diprotonated 1,4-Diazabicyclo[2.2.2]octane Shifts between Two Pyruvic Acids. Z Anorg Allg Chem 2018. [DOI: 10.1002/zaac.201800362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Ting Fang
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Yang Jie
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Yuan Huang
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Yao-Hui Ye
- The Office of Academic Affairs; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Wen-Bin Chen
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Bing-Qi Li
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Chen Zou
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Dan-Lei Xu
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
| | - Kun Qian
- College of Pharmacy; Jiangxi University of Traditional Chinese Medicine; 330004 Nanchang P. R. China
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10
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Cerreia Vioglio P, Chierotti MR, Gobetto R. Pharmaceutical aspects of salt and cocrystal forms of APIs and characterization challenges. Adv Drug Deliv Rev 2017; 117:86-110. [PMID: 28687273 DOI: 10.1016/j.addr.2017.07.001] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/23/2017] [Accepted: 07/03/2017] [Indexed: 11/28/2022]
Abstract
In recent years many efforts have been devoted to the screening and the study of new solid-state forms of old active pharmaceutical ingredients (APIs) with salification or co-crystallization processes, thus modulating final properties without changing the pharmacological nature. Salts, hydrates/solvates, and cocrystals are the common solid-state forms employed. They offer the intriguing possibility of exploring different pharmaceutical properties for a single API in the quest of enhancing the final drug product. New synthetic strategies and advanced characterization techniques have been recently proposed in this hot topic for pharmaceutical companies. This paper reviews the recent progresses in the field particularly focusing on the characterization challenges encountered when the nature of the solid-state form must be determined. The aim of this article is to offer the state-of-the-art on this subject in order to develop new insights and to promote cooperative efforts in the fascinating field of API salt and cocrystal forms.
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Affiliation(s)
| | - Michele R Chierotti
- Department of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
| | - Roberto Gobetto
- Department of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy.
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11
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Optimized multi-step NMR-crystallography approach for structural characterization of a stable quercetin solvate. J Pharm Biomed Anal 2017; 138:22-28. [DOI: 10.1016/j.jpba.2017.01.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/20/2017] [Accepted: 01/22/2017] [Indexed: 11/19/2022]
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12
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Kerr HE, Softley LK, Suresh K, Hodgkinson P, Evans IR. Structure and physicochemical characterization of a naproxen-picolinamide cocrystal. Acta Crystallogr C Struct Chem 2017; 73:168-175. [PMID: 28257010 PMCID: PMC5391861 DOI: 10.1107/s2053229616011980] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 07/22/2016] [Indexed: 01/28/2023] Open
Abstract
Naproxen (NPX) is a nonsteroidal anti-inflammatory drug with pain- and fever-relieving properties, currently marketed in the sodium salt form to overcome solubility problems; however, alternative solutions for improving its solubility across all pH values are desirable. NPX is suitable for cocrystal formation, with hydrogen-bonding possibilities via the COOH group. The crystal structure is presented of a 1:1 cocrystal of NPX with picolinamide as a coformer [systematic name: (S)-2-(6-methoxynaphthalen-2-yl)propanoic acid-pyridine-2-carboxamide (1/1), C14H14O3·C6H6N2O]. The pharmaceutically relevant physical properties were investigated and the intrinsic dissolution rate was found to be essentially the same as that of commercial naproxen. An NMR crystallography approach was used to investigate the H-atom positions in the two crystallographically unique COOH-CONH hydrogen-bonded dimers. 1H solid-state NMR distinguished the two carboxyl protons, despite the very similar crystallographic environments. The nature of the hydrogen bonding was confirmed by solid-state NMR and density functional theory calculations.
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Affiliation(s)
- Hannah E. Kerr
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, UK
| | - Lorna K. Softley
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, UK
| | - Kuthuru Suresh
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
| | - Paul Hodgkinson
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, UK
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13
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Golob S, Perry M, Lusi M, Chierotti MR, Grabnar I, Lassiani L, Voinovich D, Zaworotko MJ. Improving Biopharmaceutical Properties of Vinpocetine Through Cocrystallization. J Pharm Sci 2016; 105:3626-3633. [DOI: 10.1016/j.xphs.2016.09.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/31/2016] [Accepted: 09/16/2016] [Indexed: 01/08/2023]
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14
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Filip X, Filip C. Can the conformation of flexible hydroxyl groups be constrained by simple NMR crystallography approaches? The case of the quercetin solid forms. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 65:21-28. [PMID: 25465481 DOI: 10.1016/j.ssnmr.2014.10.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/08/2014] [Accepted: 10/23/2014] [Indexed: 06/04/2023]
Abstract
Hydrogen atoms in systems with many flexible hydroxyl side-groups are difficult to be exactly located from experimental X-Ray diffraction and/or solid-state NMR data, thus often leading to wrong conclusions with respect to the hydrogen bonding network established in crystal lattice. A simple computational method is proposed in the present work to tackle this problem, which may be readily incorporated in conventional NMR crystallography protocols. The method is based on ranking all possible conformations of the flexible hydroxyls according to their lattice energy in crystalline environments. Its effectiveness is investigated on two distinct solid forms of quercetin, for which only two out of the five hydroxyl side-groups can be well constrained from experimental/theoretical data. For this purpose, first-principle quantum-mechanical computations were combined with calculations at the molecular mechanics (MM) level of theory, and previous ss-NMR and X-Ray diffraction data. To assess accuracy in ranking the identified conformers, tests have been performed first on quercetin dihydrate, for which an X-Ray single-crystal structure is available. The possibility of applying this method in a real NMR crystallography context has been investigated finally on anhydrous quercetin, for which only powder X-Ray crystal structure has been reported so far.
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Affiliation(s)
- Xenia Filip
- National Institute for R&D of Isotopic and Molecular Technologies, P.O. Box 700, 400293 Cluj, Romania
| | - Claudiu Filip
- National Institute for R&D of Isotopic and Molecular Technologies, P.O. Box 700, 400293 Cluj, Romania.
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15
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Solid-state NMR studies of theophylline co-crystals with dicarboxylic acids. J Pharm Biomed Anal 2014; 100:322-328. [DOI: 10.1016/j.jpba.2014.07.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 07/14/2014] [Accepted: 07/16/2014] [Indexed: 11/24/2022]
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16
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Mercadal N, Day SP, Jarmyn A, Pitak MB, Coles SJ, Wilson C, Rees GJ, Hanna JV, Wallis JD. O- vs. N-protonation of 1-dimethylaminonaphthalene-8-ketones: formation of a peri N–C bond or a hydrogen bond to the pi-electron density of a carbonyl group. CrystEngComm 2014. [DOI: 10.1039/c4ce00981a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Peri-amino-naphthylketones protonate on O or N forming a long peri-N–C bond or a hydrogen bond to the ketone's π-density.
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Affiliation(s)
- Nerea Mercadal
- School of Science and Technology
- Nottingham Trent University
- Clifton Lane
- Nottingham NG11 8NS, UK
| | - Stephen P. Day
- Department of Physics
- University of Warwick
- Coventry CV4 7AL, UK
| | - Andrew Jarmyn
- School of Science and Technology
- Nottingham Trent University
- Clifton Lane
- Nottingham NG11 8NS, UK
| | - Mateusz B. Pitak
- UK National Crystallography Service, Chemistry
- University of Southampton
- Highfield Campus
- Southampton, UK
| | - Simon J. Coles
- UK National Crystallography Service, Chemistry
- University of Southampton
- Highfield Campus
- Southampton, UK
| | - Claire Wilson
- Diamond Light Source Ltd
- Harwell Science and Innovation Campus
- Didcot, UK
| | - Gregory J. Rees
- Department of Physics
- University of Warwick
- Coventry CV4 7AL, UK
| | - John V. Hanna
- Department of Physics
- University of Warwick
- Coventry CV4 7AL, UK
| | - John D. Wallis
- School of Science and Technology
- Nottingham Trent University
- Clifton Lane
- Nottingham NG11 8NS, UK
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17
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Batisai E, Ayamine A, Kilinkissa OEY, Báthori NB. Melting point–solubility–structure correlations in multicomponent crystals containing fumaric or adipic acid. CrystEngComm 2014. [DOI: 10.1039/c4ce01298d] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The relationships between the melting point, solubility and structure was investigated in a series of multicomponent crystals of fumaric and adipic acid.
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Affiliation(s)
- Eustina Batisai
- Crystal Engineering Research Unit
- Department of Chemistry
- Cape Peninsula University of Technology
- Cape Town, South Africa
| | - Alban Ayamine
- Crystal Engineering Research Unit
- Department of Chemistry
- Cape Peninsula University of Technology
- Cape Town, South Africa
| | - Ornella E. Y. Kilinkissa
- Crystal Engineering Research Unit
- Department of Chemistry
- Cape Peninsula University of Technology
- Cape Town, South Africa
| | - Nikoletta B. Báthori
- Crystal Engineering Research Unit
- Department of Chemistry
- Cape Peninsula University of Technology
- Cape Town, South Africa
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18
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Miclaus M, Grosu IG, Filip X, Tripon C, Filip C. Optimizing structure determination from powders of crystalline organic solids with high molecular flexibility: the case of lisinopril dihydrate. CrystEngComm 2014. [DOI: 10.1039/c3ce41890a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Stevens JS, Byard SJ, Seaton CC, Sadiq G, Davey RJ, Schroeder SLM. Proton transfer and hydrogen bonding in the organic solid state: a combined XRD/XPS/ssNMR study of 17 organic acid–base complexes. Phys Chem Chem Phys 2014; 16:1150-60. [DOI: 10.1039/c3cp53907e] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Filip X, Grosu IG, Miclăuş M, Filip C. NMR crystallography methods to probe complex hydrogen bonding networks: application to structure elucidation of anhydrous quercetin. CrystEngComm 2013. [DOI: 10.1039/c3ce40299a] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Chierotti MR, Gaglioti K, Gobetto R, Braga D, Grepioni F, Maini L. From molecular crystals to salt co-crystals of barbituric acid via the carbonate ion and an improvement of the solid state properties. CrystEngComm 2013. [DOI: 10.1039/c3ce40938d] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Mechanochemically induced disordered structures of vincamine: The different mediation of two cross-linked polymers. Int J Pharm 2012; 436:41-57. [DOI: 10.1016/j.ijpharm.2012.06.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/01/2012] [Accepted: 06/03/2012] [Indexed: 11/22/2022]
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23
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Álvarez CM, García-Rodríguez R, Martín-Alvarez JM, Miguel D, Turiel JA. Macrocycle Formation by Proton-Template-Induced Dimerization of Complexes with (Alkoxoimino)pyridine. Inorg Chem 2012; 51:3938-40. [DOI: 10.1021/ic300196w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Celedonio M. Álvarez
- IU CINQUIMA, Química Inorgánica, Universidad de Valladolid, E-47005 Valladolid, Spain
| | - Raúl García-Rodríguez
- IU CINQUIMA, Química Inorgánica, Universidad de Valladolid, E-47005 Valladolid, Spain
| | | | - Daniel Miguel
- IU CINQUIMA, Química Inorgánica, Universidad de Valladolid, E-47005 Valladolid, Spain
| | - José A. Turiel
- IU CINQUIMA, Química Inorgánica, Universidad de Valladolid, E-47005 Valladolid, Spain
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24
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25
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Loots L, Wahl H, van der Westhuizen L, Haynes DA, le Roex T. Interconversion between different stoichiometric forms of a three-component crystal via liquid-assisted grinding. Chem Commun (Camb) 2012; 48:11507-9. [DOI: 10.1039/c2cc36313e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Filip X, Borodi G, Filip C. Testing the limits of sensitivity in a solid-state structural investigation by combined X-ray powder diffraction, solid-state NMR, and molecular modelling. Phys Chem Chem Phys 2011; 13:17978-86. [DOI: 10.1039/c1cp21878f] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Stevens JS, Byard SJ, Muryn CA, Schroeder SLM. Identification of Protonation State by XPS, Solid-State NMR, and DFT: Characterization of the Nature of a New Theophylline Complex by Experimental and Computational Methods. J Phys Chem B 2010; 114:13961-9. [DOI: 10.1021/jp106465u] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Joanna S. Stevens
- School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K., Department of Analytical Sciences, Sanofi-Aventis Research, Willowburn Avenue, Alnwick, Northumberland, NE66 2JH, U.K., and School of Chemistry, The University of Manchester, Brunswick Street, Manchester, M13 9PL, U.K
| | - Stephen J. Byard
- School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K., Department of Analytical Sciences, Sanofi-Aventis Research, Willowburn Avenue, Alnwick, Northumberland, NE66 2JH, U.K., and School of Chemistry, The University of Manchester, Brunswick Street, Manchester, M13 9PL, U.K
| | - Christopher A. Muryn
- School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K., Department of Analytical Sciences, Sanofi-Aventis Research, Willowburn Avenue, Alnwick, Northumberland, NE66 2JH, U.K., and School of Chemistry, The University of Manchester, Brunswick Street, Manchester, M13 9PL, U.K
| | - Sven L. M. Schroeder
- School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K., Department of Analytical Sciences, Sanofi-Aventis Research, Willowburn Avenue, Alnwick, Northumberland, NE66 2JH, U.K., and School of Chemistry, The University of Manchester, Brunswick Street, Manchester, M13 9PL, U.K
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28
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Tkaczyk M, Dawidowski M, Herold F, Wolska I, Wawer I. 13C CPMAS NMR, XRD and DFT study of selected 2,6-diketopiperazines. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.03.089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Chierotti M, Ferrero L, Garino N, Gobetto R, Pellegrino L, Braga D, Grepioni F, Maini L. The Richest Collection of Tautomeric Polymorphs: The Case of 2-Thiobarbituric Acid. Chemistry 2010; 16:4347-58. [DOI: 10.1002/chem.200902485] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Jacobs A, Nassimbeni LR, Ramon G, Sebogisi BK. Inclusion compounds of hydroxynaphthoic acids: co-crystal vs. salt formation. CrystEngComm 2010. [DOI: 10.1039/c004458j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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Braga D, Dichiarante E, Palladino G, Grepioni F, Chierotti MR, Gobetto R, Pellegrino L. Remarkable reversal of melting point alternation by co-crystallization. CrystEngComm 2010. [DOI: 10.1039/c0ce00253d] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Di Nicola C, Effendy, Marchetti F, Nervi C, Pettinari C, Robinson WT, Sobolev AN, White AH. Syntheses, structures and spectroscopy of uni- and bi-dentate nitrogen base complexes of silver(i) trifluoromethanesulfonate. Dalton Trans 2010; 39:908-22. [DOI: 10.1039/b913173f] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Chierotti MR, Gobetto R. Solid‐State NMR Investigation of Ligand Mobility and Reactivity in Transition Metal Complexes. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200801205] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Michele R. Chierotti
- Dipartimento di Chimica I.F.M., Università di Torino, via P. Giuria 7, 10125 Torino, Italy, Fax: +39‐011‐6707855
| | - Roberto Gobetto
- Dipartimento di Chimica I.F.M., Università di Torino, via P. Giuria 7, 10125 Torino, Italy, Fax: +39‐011‐6707855
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34
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Braga D, Grepioni F, Maini L, Polito M, Rubini K, Chierotti M, Gobetto R. Hetero-Seeding and Solid Mixture to Obtain New Crystalline Forms. Chemistry 2009; 15:1508-15. [DOI: 10.1002/chem.200800381] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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35
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36
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Baisch U, Braga D. [Yb(C2O4)4]5−– a versatile metal–organic building block for layered coordination polymers. CrystEngComm 2009. [DOI: 10.1039/b816022h] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Braga D, Palladino G, Polito M, Rubini K, Grepioni F, Chierotti M, Gobetto R. Three Polymorphic Forms of the Co-Crystal 4,4′-Bipyridine/Pimelic Acid and their Structural, Thermal, and Spectroscopic Characterization. Chemistry 2008; 14:10149-59. [DOI: 10.1002/chem.200801051] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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38
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Khan M, Brunklaus G, Enkelmann V, Spiess HW. Transient States in [2 + 2] Photodimerization of Cinnamic Acid: Correlation of Solid-State NMR and X-ray Analysis. J Am Chem Soc 2008; 130:1741-8. [DOI: 10.1021/ja0773711] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mujeeb Khan
- Max-Planck-Institut für Polymerforschung, Postfach 31 48, D-55021 Mainz, Germany
| | - Gunther Brunklaus
- Max-Planck-Institut für Polymerforschung, Postfach 31 48, D-55021 Mainz, Germany
| | - Volker Enkelmann
- Max-Planck-Institut für Polymerforschung, Postfach 31 48, D-55021 Mainz, Germany
| | - Hans-Wolfgang Spiess
- Max-Planck-Institut für Polymerforschung, Postfach 31 48, D-55021 Mainz, Germany
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39
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Chierotti MR, Gobetto R. Solid-state NMR studies of weak interactions in supramolecular systems. Chem Commun (Camb) 2008:1621-34. [PMID: 18368147 DOI: 10.1039/b711551b] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The field of application of solid-state NMR to the study of supramolecular systems is growing rapidly, with many research groups involved in the development of techniques for the study of crystalline and amorphous phases. This Feature Article aims to provide an overview of the recent contributions of our research group to this field, paying particular attention to the study of the weak interactions such as hydrogen bonds in supramolecular systems through solid-state NMR investigations. The structure and dynamic behaviour of selected host-guest systems will be also discussed.
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Affiliation(s)
- Michele R Chierotti
- Università degli Studi di Torino, Dipartimento di Chimica I.F.M, Via P. Giuria 7, 10125 Torino, Italy
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40
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Rodríguez-Cuamatzi P, Arillo-Flores OI, Bernal-Uruchurtu MI, Höpfl H. Experimental and Theoretical Analysis of the Hydrogen-bonding Motifs Formed Between the Carboxyl and the Carboxylate Group: Towards a Systematic Classification of their Supramolecular Motifs. Supramol Chem 2007. [DOI: 10.1080/10610270701474439] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- P. Rodríguez-Cuamatzi
- a Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos , Av. Universidad 1001, C.P. 62209, Cuernavaca, México
| | - O. I. Arillo-Flores
- a Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos , Av. Universidad 1001, C.P. 62209, Cuernavaca, México
| | - M. I. Bernal-Uruchurtu
- a Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos , Av. Universidad 1001, C.P. 62209, Cuernavaca, México
| | - H. Höpfl
- a Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos , Av. Universidad 1001, C.P. 62209, Cuernavaca, México
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41
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Mifsud N, Elena B, Pickard CJ, Lesage A, Emsley L. Assigning powders to crystal structures by high-resolution (1)H-(1)H double quantum and (1)H-(13)C J-INEPT solid-state NMR spectroscopy and first principles computation. A case study of penicillin G. Phys Chem Chem Phys 2006; 8:3418-22. [PMID: 16855720 DOI: 10.1039/b605227d] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We show how powder samples at natural isotopic abundance can be assigned to crystal structures by using high-resolution proton and carbon-13 solid-state NMR spectra in combination with first principles calculations. Homonuclear proton double-quantum spectra in combination with through-bond proton-carbon HSQC spectra are used to assign the NMR spectra. We then show that the proton chemical shifts can be included in the process of assigning the spectra to a crystal structure using first principles calculations. The method is demonstrated on the K salt of penicillin G.
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Affiliation(s)
- Nicolas Mifsud
- Laboratoire de Chimie (UMR 5182 ENS/CNRS), Laboratoire de Recherche Conventionné du CEA (DSV 23V/DSM 0432), Ecole Normale Supérieure de Lyon, 46, Allée d'Italie, 69364 Lyon, France
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42
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Abstract
This review article describes the applications of NMR to the study of polymorphs and related forms (solvates) of organic (especially pharmaceutical) compounds, for which it is of increasing academic and practical importance. The nature of the systems covered is briefly introduced, as are the techniques constituting solid-state NMR. The methodologies involved are then reviewed under a number of different headings, ranging from spectral editing through relaxation times to shielding tensors and NMR crystallography. In each case the relevant applications are described. Whilst most studies concentrate on structural matters, motional effects are not neglected. A special section discusses studies of solvates (especially hydrates), and another reviews quantitative analysis.
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Affiliation(s)
- Robin K Harris
- Department of Chemistry, University of Durham, South Road, Durham, UK DH1 3LE.
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