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Klapötke TM, Pflüger C. 3‐Nitramino‐4‐nitrofurazan: Enhancing the Stability and Energetic Properties by Introduction of Alkylnitramines. Z Anorg Allg Chem 2017. [DOI: 10.1002/zaac.201700037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Thomas M. Klapötke
- Energetic Materials Research, Department of Chemistry Ludwig Maximilian University of Munich Butenandtstr. 5–13 (D) 81925 München Germany
| | - Carolin Pflüger
- Energetic Materials Research, Department of Chemistry Ludwig Maximilian University of Munich Butenandtstr. 5–13 (D) 81925 München Germany
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2
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Affiliation(s)
- Thomas M. Klapötke
- Department of Chemistry, Ludwig Maximilian University Munich, Butenandtstr. 5-13 (D), 81377 Munich, Germany
| | - Burkhard Krumm
- Department of Chemistry, Ludwig Maximilian University Munich, Butenandtstr. 5-13 (D), 81377 Munich, Germany
| | - Carolin Pflüger
- Department of Chemistry, Ludwig Maximilian University Munich, Butenandtstr. 5-13 (D), 81377 Munich, Germany
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Izsák D, Klapötke TM, Lutter FH, Pflüger C. Tailoring the Energetic Properties of 5-(5-Amino-1,2,3-triazol-4-yl)tetrazole and Its Derivatives by Salt Formation: From Sensitive Primary to Insensitive Secondary Explosives. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600108] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [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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Dippold AA, Izsák D, Klapötke TM, Pflüger C. Combining the Advantages of Tetrazoles and 1,2,3-Triazoles: 4,5-Bis(tetrazol-5-yl)-1,2,3-triazole, 4,5-Bis(1-hydroxytetrazol-5-yl)-1,2,3-triazole, and their Energetic Derivatives. Chemistry 2016. [PMID: 26744139 DOI: 10.1002/chem.v22.510.1002/chem.201504624] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In the development of new energetic materials, the main challenge is the combination of high energy content with chemical and mechanical stability, two properties that are often contradictory. In this study, the syntheses and comprehensive characterizations of 4,5-bis(tetrazole-5-yl)-1,2,3-triazole and the novel 4,5-bis(1-hydroxytetrazole-5-yl)-1,2,3-triazole, as well as their energetic properties, are presented, combining the advantages of the more energetic tetrazole and the more stable 1,2,3-triazole rings. Nitrogen-rich salts of both compounds were synthesized to investigate their detonation performances and combustion behavior calculated by computer codes for potential application in erosion-reduced gun propellant mixtures due to their high nitrogen content. The structures of several of the compounds were studied by single-crystal X-ray diffraction and, especially in the case of 4,5-bis(tetrazol-5-yl)-1,2,3-triazole, revealed the site of deprotonation.
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Affiliation(s)
- Alexander A Dippold
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377, Munich, Germany
| | - Dániel Izsák
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377, Munich, Germany
| | - Thomas M Klapötke
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377, Munich, Germany.
| | - Carolin Pflüger
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377, Munich, Germany
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Dippold AA, Izsák D, Klapötke TM, Pflüger C. Combining the Advantages of Tetrazoles and 1,2,3‐Triazoles: 4,5‐Bis(tetrazol‐5‐yl)‐1,2,3‐triazole, 4,5‐Bis(1‐hydroxytetrazol‐5‐yl)‐1,2,3‐triazole, and their Energetic Derivatives. Chemistry 2016; 22:1768-78. [DOI: 10.1002/chem.201504624] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Alexander A. Dippold
- Department of Chemistry Ludwig Maximilian University of Munich (LMU) Butenandtstr. 5–13 81377 Munich Germany
| | - Dániel Izsák
- Department of Chemistry Ludwig Maximilian University of Munich (LMU) Butenandtstr. 5–13 81377 Munich Germany
| | - Thomas M. Klapötke
- Department of Chemistry Ludwig Maximilian University of Munich (LMU) Butenandtstr. 5–13 81377 Munich Germany
| | - Carolin Pflüger
- Department of Chemistry Ludwig Maximilian University of Munich (LMU) Butenandtstr. 5–13 81377 Munich Germany
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Klapötke TM, Penger A, Pflüger C, Stierstorfer J. Melt-cast materials: combining the advantages of highly nitrated azoles and open-chain nitramines. NEW J CHEM 2016. [DOI: 10.1039/c6nj00202a] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [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
Combination of the nitramine 1-chloro-2-nitrazapropane and nitro-substituted azoles yielded energetic materials for potential use as TNT replacements in melt-cast formulations.
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Affiliation(s)
| | - Alexander Penger
- Department of Chemistry
- Ludwig Maximilian University
- 81377 Munich
- Germany
| | - Carolin Pflüger
- Department of Chemistry
- Ludwig Maximilian University
- 81377 Munich
- Germany
| | - Jörg Stierstorfer
- Department of Chemistry
- Ludwig Maximilian University
- 81377 Munich
- Germany
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Klapötke TM, Pflüger C, Reintinger MW. Energetic Materials Based on 5,7‐Dinitrobenzotriazole and 4,6‐Dinitrobenzotriazol‐3‐ium 1‐Oxide Derivatives. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201501126] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Thomas M. Klapötke
- Department of Chemistry, Ludwig Maximilian University of Munich, Butenandtstr. 5–13, 81377 München, Germany, http://www.hedm.cup.uni‐muenchen.de
| | - Carolin Pflüger
- Department of Chemistry, Ludwig Maximilian University of Munich, Butenandtstr. 5–13, 81377 München, Germany, http://www.hedm.cup.uni‐muenchen.de
| | - Markus W. Reintinger
- Department of Chemistry, Ludwig Maximilian University of Munich, Butenandtstr. 5–13, 81377 München, Germany, http://www.hedm.cup.uni‐muenchen.de
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Ehlers D, Klapötke TM, Pflüger C. Investigations of the Vicarious C-Aminations of 5,7-Dinitrobenzotriazole and 4,6-Dinitrobenzotriazol-3-ium-1-oxide and Their Energetic Properties. Chemistry 2015; 21:16073-82. [PMID: 26397388 DOI: 10.1002/chem.201502812] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [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: 07/17/2015] [Indexed: 11/09/2022]
Abstract
This combined experimental and theoretical study details the vicarious nucleophilic substitution by amination of 5,7-dinitrobenzotriazol (1) and 4,6-dinitrobenzotriazole-3-ium-1-oxide (4) with trimethylhydrazinium iodide to afford the new corresponding one- and two-time aminated compounds and investigations of its mechanism by EPR spectroscopy. The preferred position for the first amination is computed by spin density population and verified by X-ray crystallography. The zwitterionic structure of 4 is investigated in solution by (1) H NMR spectroscopy and in solid state by X-ray diffraction. Furthermore, the crystal structure of 1 is presented. The energetic behavior of the aminated products as well as the starting materials 1 and 4 was investigated, regarding sensitivities and performance.
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Affiliation(s)
- Dieter Ehlers
- Department of Physics, University of Augsburg, Universitätsstrasse 1, 86135 Augsburg (Germany)
| | - Thomas M Klapötke
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377 Munich (Germany).
| | - Carolin Pflüger
- Department of Chemistry, Ludwig Maximilian University of Munich (LMU), Butenandtstr. 5-13, 81377 Munich (Germany)
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Abstract
This study presents the preparation of the novel nitrogen-rich compound 5-(5-amino-2H-1,2,3-triazol-4-yl)-1H-tetrazole (5) in a five step synthesis, and additionally its more energetic derivatives with azido (6) and nitro (7) groups, as well as a diazene bridge (8).
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Affiliation(s)
- Dániel Izsák
- Department of Chemistry
- Ludwig–Maximilian University of Munich
- 81377 Munich
- Germany
| | - Thomas M. Klapötke
- Department of Chemistry
- Ludwig–Maximilian University of Munich
- 81377 Munich
- Germany
| | - Carolin Pflüger
- Department of Chemistry
- Ludwig–Maximilian University of Munich
- 81377 Munich
- Germany
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Klapötke TM, Penger A, Pflüger C, Stierstorfer J, Sućeska M. Advanced Open-Chain Nitramines as Energetic Materials: Heterocyclic-Substituted 1,3-Dichloro-2-nitrazapropane. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300382] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Steinkamp M, Schulte N, Spaniol U, Pflüger C, Hartmann C, Kirsch J, von Boyen GB. Brain derived neurotrophic factor inhibits apoptosis in enteric glia during gut inflammation. Med Sci Monit 2012; 18:BR117-22. [PMID: 22460084 PMCID: PMC3560818 DOI: 10.12659/msm.882612] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [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] [Indexed: 12/23/2022] Open
Abstract
Background Enteric glia cells (EGCs) are essential for the integrity of the bowel. A loss of EGCs leads to a severe inflammation of the intestines. As a diminished EGC network is postulated in Crohn’s disease (CD), we aimed to investigate if EGCs could be a target of apoptosis during inflammation in CD, which can be influenced by Brain derived neurotrophic factor (BDNF). Material/Methods GFAP, BDNF and cCaspase-3 were detected in the gut of patients with CD. Primary EGC cultures were established and cultivated. Tyrosine receptor kinase (TrkB) receptors on these cells were investigated by western blot and immunofluorescence. Rate of apoptosis was induced by tumor necrosis factor (TNF-α) and interferon (IFN-γ). Apoptosis was determined by a fluorometric caspase 3/7 activation assay after preincubation of these cells with BDNF or neutralizing anti-BDNF antibodies. Results Mucosal GFAP-positive EGCs undergo apoptosis revealed by cCaspase-3 in the gut of patients with CD expressing BDNF highly. The combination of TNF-α and IFN-γ was able to induce apoptosis in primary EGCs, whereas these factors alone did not. Brain derived neurotrophic factor (BDNF) attenuate glia cell apoptosis to a small extent, but neutralizing antibodies against BDNF dramatically increased apoptosis. Conclusions Mucosal EGC apoptosis is an important finding in the gut of patients with CD. Proinflammatory cytokines, which are highly increased in CD, induce EGC apoptosis, whereas the neurotrophin BDNF might be protective for EGC. Since EGCs are implicated in the maintenance of the enteric mucosal integrity, EGC apoptosis may contribute to the pathophysiological changes in CD.
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Affiliation(s)
- Martin Steinkamp
- Department of Gastroenterology, Endocrinology and Metabolism, University of Marburg, Marburg, Germany
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Schuh E, Pflüger C, Citta A, Folda A, Rigobello MP, Bindoli A, Casini A, Mohr F. Gold(I) carbene complexes causing thioredoxin 1 and thioredoxin 2 oxidation as potential anticancer agents. J Med Chem 2012; 55:5518-28. [PMID: 22621714 DOI: 10.1021/jm300428v] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Gold(I) complexes with 1,3-substituted imidazole-2-ylidene and benzimidazole-2-ylidene ligands of the type NHC-Au-L (NHC = N-heterocyclic carbene L = Cl or 2-mercapto-pyrimidine) have been synthesized and structurally characterized. The compounds were evaluated for their antiproliferative properties in human ovarian cancer cells sensitive and resistant to cisplatin (A2780S/R), as well in the nontumorigenic human embryonic kidney cell line (HEK-293T), showing in some cases important cytotoxic effects. Some of the complexes were comparatively tested as thioredoxin reductase (TrxR) and glutathione reductase (GR) inhibitors, directly against the purified proteins or in cell extracts. The compounds showed potent and selective TrxR inhibition properties in particular in cancer cell lines. Remarkably, the most effective TrxR inhibitors induced extensive oxidation of thioredoxins (Trxs), which was more relevant in the cancerous cells than in HEK-293T cells. Additional biochemical assays on glutathione systems and reactive oxygen species formation evidenced important differences with respect to the classical cytotoxic Au(I)-phosphine compound auranofin.
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Affiliation(s)
- Esther Schuh
- Fachbereich C, Anorganische Chemie, Bergische Universität Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany
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Niess JH, Klaus J, Stephani J, Pflüger C, Degenkolb N, Spaniol U, Mayer B, Lahr G, von Boyen GBT. NOD2 polymorphism predicts response to treatment in Crohn's disease--first steps to a personalized therapy. Dig Dis Sci 2012; 57:879-86. [PMID: 22147245 PMCID: PMC3306782 DOI: 10.1007/s10620-011-1977-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 11/09/2011] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND AIMS Great efforts have been made to predict disease behavior over time and the response to treatment in Crohn's disease (CD). Such understanding could personalize therapy. Early introduction of more aggressive therapies to patients at high risk and no introduction of predictable refractory treatments could become possible. We hence tested the influence of the NOD2 carrier status on treatment response. PATIENTS AND METHODS In 185 CD patients (age 45 ± 9.8 years, female n = 108, minimum disease duration 10 years), the three most common polymorphisms (p.Arg702Trp, p.Gly908Arg, p.Leu1007fsX1008) of NOD2 were tested by polymerase chain reaction and sequencing. Detailed clinical and medical history were obtained with a standardized questionnaire and by reviewing the medical charts. Treatments introduced were chosen by physicians blinded to genotype data. RESULTS The frequency of the NOD2 variant allele was about one-third (67, 30.2%) of CD patients. NOD2 carriers were more often treated with systemic and locally active steroids and with an immunosuppressant (Azathioprine/6-MP). NOD2 mutation carrier status was more often associated with systemic steroid [8.9% vs. wild-type (WT) 1.2%, P = 0.0086] and local-steroid refractory (14.9% vs. WT 3.5%; P = 0.001). The WT patients were significantly higher refractory to immunosuppressant (12.8% vs. NOD2 carriers, 0.5%, P = 0.03). Most WT patients were treated with TNF-α antagonists and remission rates were significantly higher in this group after 1 year of treatment (84% vs. NOD2 carriers, 33%, P = 0.07). CONCLUSIONS The study presents first hints for the NOD2 carrier status to be predictive for response to therapy. A higher percentage of CD patients with NOD2 mutation carrier status was steroid refractory but could be treated well with immunosuppressants. The WT status showed a higher response to steroids and remission rates within 1 year of anti-TNF-α therapy. On the way to personalized medicine, this approach should be further investigated in larger studies.
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Affiliation(s)
- Jan Hendrik Niess
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Jochen Klaus
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Johannes Stephani
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Carolin Pflüger
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Nadine Degenkolb
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Ulrike Spaniol
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | | | - Georgia Lahr
- Department of Paediatrics, Ulm University, Ulm, Germany
| | - Georg B. T. von Boyen
- Department of Medicine I (Gastroenterology), Ulm University, Albert-Einstein-Allee 23, 89081 Ulm, Germany
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von Boyen GBT, Schulte N, Pflüger C, Spaniol U, Hartmann C, Steinkamp M. Distribution of enteric glia and GDNF during gut inflammation. BMC Gastroenterol 2011; 11:3. [PMID: 21235736 PMCID: PMC3034687 DOI: 10.1186/1471-230x-11-3] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 01/14/2011] [Indexed: 12/19/2022] Open
Abstract
Background The enteric glia network may be involved in the pathogenesis of inflammatory bowel disease (IBD). Enteric glia cells (EGCs) are the major source of glial-derived neurotrophic factor (GDNF), which regulates apoptosis of enterocytes. The aim of the study was to determine the distribution of EGCs and GDNF during gut inflammation and to elucidate a possible diminished enteric glia network in IBD. Methods The expression of glial fibrillary acidic protein (GFAP) in colonic biopsies of patients with IBD, controls and patients with infectious colitis was detected by immunohistochemistry and Western blot. Tissue GDNF levels were measured by ELISA. Results The expression of GFAP and GDNF in the mucosal plexus is highly increased in the inflamed colon of patients with ulcerative colitis (UC) and infectious colitis. Although the GDNF and GFAP content are increased in Crohn's disease (CD), it is significantly less. Additionally the non-inflamed colon of CD patients showed a reduced GFAP and no GDNF expression compared to controls and the non-inflamed colon of UC patients. Conclusions GFAP and GDNF as signs of activated EGCs are increased in the inflamed mucosa of patients with UC and infectious colitis, which underline an unspecific role of EGC in the regulation of intestinal inflammation. The reduced GFAP and GDNF content in the colon of CD patients suggest a diminished EGC network in this disease. This might be a part of the pathophysiological puzzle of CD.
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