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Wagner F, Sagmeister P, Jusner CE, Tampone TG, Manee V, Buono FG, Williams JD, Kappe CO. A Slug Flow Platform with Multiple Process Analytics Facilitates Flexible Reaction Optimization. Adv Sci (Weinh) 2024; 11:e2308034. [PMID: 38273711 PMCID: PMC10987115 DOI: 10.1002/advs.202308034] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/21/2023] [Indexed: 01/27/2024]
Abstract
Flow processing offers many opportunities to optimize reactions in a rapid and automated manner, yet often requires relatively large quantities of input materials. To combat this, the use of a flexible slug flow reactor, equipped with two analytical instruments, for low-volume optimization experiments are reported. A Buchwald-Hartwig amination toward the drug olanzapine, with 6 independent optimizable variables, is optimized using three different automated approaches: self-optimization, design of experiments, and kinetic modeling. These approaches are complementary and provide differing information on the reaction: pareto optimal operating points, response surface models, and mechanistic models, respectively. The results are achieved using <10% of the material that would be required for standard flow operation. Finally, a chemometric model is built utilizing automated data handling and three subsequent validation experiments demonstrate good agreement between the slug flow reactor and a standard (larger scale) flow reactor.
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Affiliation(s)
- Florian Wagner
- Center for Continuous Flow Synthesis and Processing (CC FLOW)Research Center Pharmaceutical Engineering GmbH (RCPE)Inffeldgasse 13Graz8010Austria
- Institute of ChemistryUniversity of GrazNAWI Graz, Heinrichstrasse 28Graz8010Austria
| | - Peter Sagmeister
- Center for Continuous Flow Synthesis and Processing (CC FLOW)Research Center Pharmaceutical Engineering GmbH (RCPE)Inffeldgasse 13Graz8010Austria
- Institute of ChemistryUniversity of GrazNAWI Graz, Heinrichstrasse 28Graz8010Austria
| | - Clemens E. Jusner
- Center for Continuous Flow Synthesis and Processing (CC FLOW)Research Center Pharmaceutical Engineering GmbH (RCPE)Inffeldgasse 13Graz8010Austria
- Institute of ChemistryUniversity of GrazNAWI Graz, Heinrichstrasse 28Graz8010Austria
| | - Thomas G. Tampone
- Boehringer Ingelheim Pharmaceuticals, Inc900 Ridgebury RoadRidgefieldCT06877USA
| | - Vidhyadhar Manee
- Boehringer Ingelheim Pharmaceuticals, Inc900 Ridgebury RoadRidgefieldCT06877USA
| | - Frederic G. Buono
- Boehringer Ingelheim Pharmaceuticals, Inc900 Ridgebury RoadRidgefieldCT06877USA
| | - Jason D. Williams
- Center for Continuous Flow Synthesis and Processing (CC FLOW)Research Center Pharmaceutical Engineering GmbH (RCPE)Inffeldgasse 13Graz8010Austria
- Institute of ChemistryUniversity of GrazNAWI Graz, Heinrichstrasse 28Graz8010Austria
| | - C. Oliver Kappe
- Center for Continuous Flow Synthesis and Processing (CC FLOW)Research Center Pharmaceutical Engineering GmbH (RCPE)Inffeldgasse 13Graz8010Austria
- Institute of ChemistryUniversity of GrazNAWI Graz, Heinrichstrasse 28Graz8010Austria
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Umabharathi SB, Neetha M, Anilkumar G. Palladium N-Heterocyclic Carbene-Catalyzed Aminations: An Outline. Top Curr Chem (Cham) 2024; 382:3. [PMID: 38265533 DOI: 10.1007/s41061-024-00449-w] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 01/04/2024] [Indexed: 01/25/2024]
Abstract
Amination reactions play a pivotal role in synthetic organic chemistry, facilitating the generation of nitrogen-containing scaffolds with broad applications in drug synthesis, material production, polymer formation, and the generation of amino acids and peptides. Amination offers the potential to fine tune the properties of natural products and produce functional materials for various applications. Palladium N-heterocyclic carbene (Pd-NHC) emerges as an innovative and highly effective catalyst in this context. Under favorable reaction conditions, this robust and simple catalyst efficiently facilitates the synthesis of a diverse range of compounds with varying complexity and utility. Pd-NHC complexes exhibit significant σ-electron donating potential, enhancing the ease of the oxidative addition process in their mechanistic pathway. Their steric topography further contributes to a rapid reductive elimination. These complexes demonstrate remarkable stability, a result of the strong Pd-ligand bond. The wide variety of Pd-NHC complexes has proven highly efficient in catalyzing reactions across a spectrum of complexities, from simple to intricate. The domain of aminations catalyzed by Pd-NHC has undergone significant diversification, presenting new opportunities, particularly in the realms of material chemistry and natural product synthesis. This review outlines the advancements in Pd-NHC-catalyzed amination reactions, covering literature up to date.
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Affiliation(s)
- S B Umabharathi
- School of Physical Sciences, Amrita Vishwa Vidyapeetham, Amritapuri Campus, Clappana P. O., Kollam, Kerala, 690525, India
| | - Mohan Neetha
- School of Chemical Sciences, Mahatma Gandhi University, Priyadarsini Hills P. O., Kottayam, Kerala, 686560, India
| | - Gopinathan Anilkumar
- School of Chemical Sciences, Mahatma Gandhi University, Priyadarsini Hills P. O., Kottayam, Kerala, 686560, India.
- Institute for Integrated Programs and Research in Basic Sciences (IIRBS), Mahatma Gandhi University, Priyadarsini Hills P. O., Kottayam, Kerala, 686560, India.
- Advanced Molecular Materials Research Center (AMMRC), Mahatma Gandhi University, Priyadarsini Hills P. O., Kottayam, Kerala, 686560, India.
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Romanelli MN, Braconi L, Gabellini A, Manetti D, Marotta G, Teodori E. Synthetic Approaches to Piperazine-Containing Drugs Approved by FDA in the Period of 2011-2023. Molecules 2023; 29:68. [PMID: 38202651 PMCID: PMC10780301 DOI: 10.3390/molecules29010068] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
The piperazine moiety is often found in drugs or in bioactive molecules. This widespread presence is due to different possible roles depending on the position in the molecule and on the therapeutic class, but it also depends on the chemical reactivity of piperazine-based synthons, which facilitate its insertion into the molecule. In this paper, we take into consideration the piperazine-containing drugs approved by the Food and Drug Administration between January 2011 and June 2023, and the synthetic methodologies used to prepare the compounds in the discovery and process chemistry are reviewed.
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Affiliation(s)
- Maria Novella Romanelli
- Section of Pharmaceutical and Nutraceutical Science, Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Via Ugo Schiff, 6, Sesto Fiorentino, 50019 Florence, Italy; (L.B.); (A.G.); (D.M.); (G.M.); (E.T.)
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Razmienė B, Vojáčková V, Řezníčková E, Malina L, Dambrauskienė V, Kubala M, Bajgar R, Kolářová H, Žukauskaitė A, Arbačiauskienė E, Šačkus A, Kryštof V. Synthesis of N-aryl-2,6-diphenyl-2H-pyrazolo[4,3-c]pyridin-7-amines and their photodynamic properties in the human skin melanoma cell line G361. Bioorg Chem 2021; 119:105570. [PMID: 34953323 DOI: 10.1016/j.bioorg.2021.105570] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 07/08/2021] [Revised: 12/10/2021] [Accepted: 12/14/2021] [Indexed: 01/05/2023]
Abstract
A small series of N-aryl-2,6-diphenyl-2H-pyrazolo[4,3-c]pyridin-7-amines was synthesized from easily accessible 1-phenyl-1H-pyrazol-3-ol via 7-iodo-2,6-diphenyl-2H-pyrazolo[4,3-c]pyridine and 7-iodo-4-methyl-2,6-diphenyl-2H-pyrazolo[4,3-c]pyridine intermediates and their subsequent use in palladium catalyzed Buchwald-Hartwig cross-coupling reaction with various anilines. Majority of the compounds were not significantly cytotoxic to melanoma G361 cells in the dark up to 10 µM concentration, but their activity could be increased by irradiation with visible blue light (414 nm). The most active compound 10 possessed EC50 values of 3.5, 1.6 and 0.9 µM in cells irradiated with 1, 5 and 10 J/cm2, respectively. The treatment caused generation of reactive oxygen species in cells and extensive DNA damage, documented by the comet assay and by detection of phosphorylated histone H2A.X, followed by apoptotic cell death. Our results suggest that N-aryl-2,6-diphenyl-2H-pyrazolo[4,3-c]pyridin-7-amines could serve as a potential source of photosensitizing compounds with anticancer activities.
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Affiliation(s)
- Beatričė Razmienė
- Department of Organic Chemistry, Kaunas University of Technology, Radvilėnų pl. 19, Kaunas LT-50254, Lithuania; Institute of Synthetic Chemistry, Kaunas University of Technology, K. Baršausko g. 59, Kaunas LT-51423, Lithuania
| | - Veronika Vojáčková
- Depatment of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Eva Řezníčková
- Depatment of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Lukáš Malina
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Vaida Dambrauskienė
- Department of Organic Chemistry, Kaunas University of Technology, Radvilėnų pl. 19, Kaunas LT-50254, Lithuania
| | - Martin Kubala
- Department of Experimental Physics, Faculty of Science, Palacký University, 17. listopadu 12, Olomouc CZ-77146, Czech Republic
| | - Robert Bajgar
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Hana Kolářová
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Asta Žukauskaitė
- Department of Chemical Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic.
| | - Eglė Arbačiauskienė
- Department of Organic Chemistry, Kaunas University of Technology, Radvilėnų pl. 19, Kaunas LT-50254, Lithuania.
| | - Algirdas Šačkus
- Department of Organic Chemistry, Kaunas University of Technology, Radvilėnų pl. 19, Kaunas LT-50254, Lithuania; Institute of Synthetic Chemistry, Kaunas University of Technology, K. Baršausko g. 59, Kaunas LT-51423, Lithuania
| | - Vladimír Kryštof
- Depatment of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
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Oeser P, Koudelka J, Petrenko A, Tobrman T. Recent Progress Concerning the N-Arylation of Indoles. Molecules 2021; 26:molecules26165079. [PMID: 34443667 PMCID: PMC8402097 DOI: 10.3390/molecules26165079] [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: 07/31/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
This review summarizes the current state-of-the-art procedures in terms of the preparation of N-arylindoles. After a short introduction, the transition-metal-free procedures available for the N-arylation of indoles are briefly discussed. Then, the nickel-catalyzed and palladium-catalyzed N-arylation of indoles are both discussed. In the next section, copper-catalyzed procedures for the N-arylation of indoles are described. The final section focuses on recent findings in the field of biologically active N-arylindoles.
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Wambua V, Hirschi JS, Vetticatt MJ. Rapid Evaluation of the Mechanism of Buchwald-Hartwig Amination and Aldol Reactions Using Intramolecular 13C Kinetic Isotope Effects. ACS Catal 2021; 11:60-67. [PMID: 34659873 DOI: 10.1021/acscatal.0c04752] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A practical approach is introduced for the rapid determination of 13C kinetic isotope effects that utilizes a "designed" reactant with two identical reaction sites. The mechanism of the Buchwald-Hartwig amination of tert-butylbromobenzene with primary and secondary amines is investigated under synthetically relevant catalytic conditions using traditional intermolecular 13C NMR methodology at natural abundance. Switching to 1,4-dibromobenzene, a symmetric bromoarene as the designed reactant, the same experimental 13C KIEs are determined using an intramolecular KIE approach. This rapid methodology for KIE determination requires substantially less material and time compared to traditional approaches. Details of the Buchwald-Hartwig amination mechanism are investigated under varying synthetic conditions, namely a variety of halides and bases. The enantioselectivity-determining step of the l-proline catalyzed aldol reaction is also evaluated using this approach. We expect this mechanistic methodology to gain traction among synthetic chemists as a practical technique to rapidly obtain high-resolution information regarding the transition structure of synthetically relevant reactions under catalytic conditions.
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Affiliation(s)
- Victor Wambua
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Jennifer S. Hirschi
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Mathew J. Vetticatt
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
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Zippel C, Spuling E, Hassan Z, Polamo M, Nieger M, Bräse S. Controlling Regioselectivity in Palladium-Catalyzed C-H Activation/Aryl-Aryl Coupling of 4-Phenylamino[2.2]paracyclophane. Chemistry 2020; 26:13771-13775. [PMID: 33245570 PMCID: PMC7693239 DOI: 10.1002/chem.202003709] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Indexed: 12/13/2022]
Abstract
Selective activation/functionalization of C-H bonds has emerged as an atom- and step-economical process at the forefront of modern synthetic chemistry. This work reports palladium-catalyzed exclusively para-selective C-H activation/aryl-aryl bond formation with a preference over N-arylation under the Buchwald-Hartwig amination reaction of 4-phenylamino[2.2]paracyclophane. This innovative synthetic strategy allows a facile preparation of [2.2]paracyclophane derivatives featuring disparate para-substitutions at C-4 and C-7 positions in a highly selective manner, gives access to a series of potential candidates for [2.2]paracyclophane-derived new planar chiral ligands. The unprecedented behavior in reactivity and preferential selectivity of C-C coupling over C-N bond formation via C-H activation is unique to the [2.2]paracyclophane scaffold compared to the non-cyclophane analogue under the same reaction conditions. Selective C-H activation/aryl-aryl bond formation and sequential C-N coupling product formation is evidenced unambiguously by X-ray crystallography.
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Affiliation(s)
- Christoph Zippel
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
| | - Eduard Spuling
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
| | - Zahid Hassan
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
- 3D Matter Made To Order—Cluster of Excellence (EXC-2082/1–390761711)Karlsruhe Institute of Technology (KIT)76131KarlsruheGermany
| | - Mika Polamo
- Department of ChemistryUniversity of HelsinkiP. O. Box 5500014HelsinkiFinland
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiP. O. Box 5500014HelsinkiFinland
| | - Stefan Bräse
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
- 3D Matter Made To Order—Cluster of Excellence (EXC-2082/1–390761711)Karlsruhe Institute of Technology (KIT)76131KarlsruheGermany
- Institute of Biological and Chemical SystemsFunctional Molecular Systems (IBCS-FMS)Karlsruhe Institute of Technology (KIT)Hermann-von-Helmholtz-Platz 176344Eggenstein-LeopoldshafenGermany
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Vogt A, Henne F, Wetzel C, Mena-Osteritz E, Bäuerle P. Synthesis and characterization of S,N-heterotetracenes. Beilstein J Org Chem 2020; 16:2636-2644. [PMID: 33178354 PMCID: PMC7607432 DOI: 10.3762/bjoc.16.214] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/15/2020] [Indexed: 01/18/2023] Open
Abstract
The synthesis and optoelectronic properties of novel S,N-heterotetracenes consisting of fused heterocyclic thiophene and pyrrole rings are presented. Tetracyclic and benzannulated derivatives with a varying number and sequence of sulfur and nitrogen heteroatoms were synthesized in multistep synthetic routes. A Buchwald-Hartwig amination of brominated precursors, thermolysis of azide precursors, and a Cadogan reaction of nitro-substituted precursors were successfully applied to eventually build-up pyrrole rings to stable and soluble fused systems. The various obtained heteroatom sequences 'SSNS' (SN4), 'SNNS' (SN4''), and 'NSSN' (SN4') allowed for evaluation of structure-property relationships relative to the sulfur analogue tetrathienoacene ('SSSS'). In line with the results for the whole series of S,N-heteroacenes, we find that replacement of sulfur by nitrogen atoms in the tetra- and hexacyclic systems leads to a red-shift in absorption, a decrease in oxidation potential and energy gap. On the other hand, the replacement of a thiophene ring by benzene leads to the opposite effects.
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Affiliation(s)
- Astrid Vogt
- Institute of Organic Chemistry II and Advanced Materials, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Florian Henne
- Institute of Organic Chemistry II and Advanced Materials, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.,Carl Zeiss SMT GmbH, Rudolf-Eber-Straße 2, 73447 Oberkochen, Germany
| | - Christoph Wetzel
- Institute of Organic Chemistry II and Advanced Materials, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.,Merck KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Elena Mena-Osteritz
- Institute of Organic Chemistry II and Advanced Materials, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Peter Bäuerle
- Institute of Organic Chemistry II and Advanced Materials, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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Bacsa I, Szemerédi D, Wölfling J, Schneider G, Fekete L, Mernyák E. The first Pd-catalyzed Buchwald-Hartwig aminations at C-2 or C-4 in the estrone series. Beilstein J Org Chem 2018; 14:998-1003. [PMID: 29977371 PMCID: PMC6009172 DOI: 10.3762/bjoc.14.85] [Citation(s) in RCA: 7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 04/13/2018] [Indexed: 01/26/2023] Open
Abstract
A facile Pd-catalyzed C(sp2)–N coupling to provide a range of 2- or 4-[(subst.)phenyl]amino-13α-estrone derivatives has been achieved under microwave irradiation. The reactions were mediated with the use of Pd(OAc)2 as a catalyst and KOt-Bu as a base in the presence of X-Phos as a ligand. The desired products have been obtained in good to excellent yields. The nature and the position of the aniline substituent at the aromatic ring influenced the outcome of the couplings. 2-Amino-13α-estrone was also synthesized in a two-step protocol including an amination of 2-bromo-13α-estrone 3-benzyl ether with benzophenone imine and subsequent hydrogenolysis.
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Affiliation(s)
- Ildikó Bacsa
- Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - Dávid Szemerédi
- Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - János Wölfling
- Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - Gyula Schneider
- Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - Lilla Fekete
- Department of Medicinal Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - Erzsébet Mernyák
- Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
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Abstract
The mol-ecular structure of the title compound, C8H11N3O, is nearly planar despite the chair conformation of the morpholine moiety. In the crystal, the mol-ecules form sheets parallel to the b axis, which are supported by non-classical hydrogen-bonding inter-actions between C-H functionalities and the O atom of morpholine and the 4-N atom of pyrazine, respectively. The title compound crystallizes in the monoclinic space group P21/c with four mol-ecules in the unit cell.
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Affiliation(s)
- Siva Sankar Murthy Bandaru
- Institut für Biochemie, Ernst-Moritz-Arndt Universität Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Anant Ramakant Kapdi
- Department of Chemistry, Institute of Chemical Technology, Nathalal Parekh Road, Matunga, Mumbai 400 019, India
| | - Carola Schulzke
- Institut für Biochemie, Ernst-Moritz-Arndt Universität Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
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