1
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Hammouda MM, Gaffer HE, Elattar KM. Insights into the medicinal chemistry of heterocycles integrated with a pyrazolo[1,5- a]pyrimidine scaffold. RSC Med Chem 2022; 13:1150-1196. [PMID: 36325400 PMCID: PMC9580358 DOI: 10.1039/d2md00192f] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/25/2022] [Indexed: 09/10/2023] Open
Abstract
Pyrazolo[1,5-a]pyrimidines are the dominant motif of many drugs; for instance, zaleplon and indiplon are sedative agents and ocinaplon was identified as an anxiolytic agent. The importance of this class of compounds lies in its varied and significant biological activities, and accordingly, considerable methods have been devised to prepare these compounds. Hence, other derivatives of this class of compounds were prepared by substitution reactions with different nucleophiles exploiting the activity of groups linked to the ring carbon and nitrogen atoms. The methods used vary through the condensation reactions of the aminopyrazoles with 1,2-allenic, enaminonitriles, enaminones, 1,3-diketones, unsaturated nitriles, or unsaturated ketones. Alternatively, these compounds are prepared through the reactions of acyclic reagents, as these methods were recently developed efficiently with high yields. The current review highlighted the recent progress of the therapeutic potential of pyrazolo[1,5-a]pyrimidines as antimicrobial, anticancer, antianxiety, anti-proliferative, analgesic, and antioxidant agents, carboxylesterase, translocator protein and PDE10A inhibitors, and selective kinase inhibitors.
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Affiliation(s)
- Mohamed M Hammouda
- Department of Chemistry, College of Science and Humanities in Al-Kharj, Prince Sattam Bin Abdulaziz University Al-Kharj 11942 Saudi Arabia
- Chemistry Department, Faculty of Science, Mansoura University El-Gomhoria Street Mansoura 35516 Egypt
| | - Hatem E Gaffer
- Dyeing and Printing Department, Textile Research Division, National Research Center Dokki Cairo 12622 Egypt
| | - Khaled M Elattar
- Unit of Genetic Engineering and Biotechnology, Faculty of Science, Mansoura University El-Gomhoria Street Mansoura 35516 Egypt +201010655354
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2
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Chen DY, Song S, Chen LY, Ren X, Li Y. Organo-catalyzed Michael addition of 2-fluoro-2-arylacetonitriles. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.152919] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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3
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Jismy B, Guillaumet G, Akssira M, Tikad A, Abarbri M. Efficient microwave-assisted Suzuki–Miyaura cross-coupling reaction of 3-bromo pyrazolo[1,5- a]pyrimidin-5(4 H)-one: towards a new access to 3,5-diarylated 7-(trifluoromethyl)pyrazolo[1,5- a]pyrimidine derivatives. RSC Adv 2021; 11:1287-1302. [PMID: 35747396 PMCID: PMC9134006 DOI: 10.1039/d0ra07959f] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/06/2020] [Indexed: 12/24/2022] Open
Abstract
A convenient and efficient synthetic route to C3-arylated 7-trifluoromethylpyrazolo[1,5-a]pyrimidin-5-one derivatives has been reported starting from 3-bromo-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-5-one through a Suzuki–Miyaura cross-coupling reaction. The arylation (heteroarylation) strategy can be performed using a wide variety of aryl and heteroaryl boronic acids and requiring a tandem catalyst XPhosPdG2/XPhos to avoid the debromination reaction. These optimized conditions were successfully extended to the synthesis of 7-, 8- and 9-arylated pyrimido[1,2-b]indazol-2-ones from their corresponding brominated starting materials. Furthermore, the second C-5 arylation of C3-arylated pyrazolo[1,5-a]pyrimidin-5-ones was achieved under standard Suzuki–Miyaura cross-coupling conditions, after activating the C–O bond of the lactam function with PyBroP, giving access to a small library of 3,5-diarylated 7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidines in good to excellent yields. The interest of this approach has been highlighted by the synthesis of a known anti-inflammatory agent. Additionally, a preliminary biological evaluation has revealed that a number of derivatives display micromolar IC50 values against monoamine oxidase B, an important target in the field of neurodegenerative disorders. A convenient and efficient synthetic route to C3-arylated 7-trifluoromethylpyrazolo[1,5-a]pyrimidin-5-one derivatives has been reported starting from 3-bromo-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-5-one through a Suzuki–Miyaura cross-coupling reaction.![]()
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Affiliation(s)
- Badr Jismy
- Laboratoire de Physico-Chimie des Matériaux et des Electrolytes pour l'Energie (PCM2E). EA 6299
- Faculté des Sciences
- 37200 Tours
- France
| | - Gérald Guillaumet
- Institut de Chimie Organique et Analytique (ICOA)
- Université d'Orléans
- UMR CNRS 7311
- France
| | - Mohamed Akssira
- Laboratoire de Chimie Physique et de Chimie Bioorganique
- URAC 22
- 28800 Mohammedia
- Morocco
| | - Abdellatif Tikad
- Laboratoire de Chimie Moléculaire et Substances Naturelles
- Faculté des Sciences
- Département de Chimie
- Université Moulay Ismail
- Meknès 50050
| | - Mohamed Abarbri
- Laboratoire de Physico-Chimie des Matériaux et des Electrolytes pour l'Energie (PCM2E). EA 6299
- Faculté des Sciences
- 37200 Tours
- France
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4
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Abstract
This review describes the non-exhaustive scenery of the synthesis of various
biologically interesting pyrimidine annulated five-membered heterocyclic ring systems
that have been appeared in the literature during the last two decades. During this period,
different synthetic routes and various methodologies have been developed for the functionalization
of pyrimidine ring towards the construction of five-membered heterocyclic
rings. The aim of this review is to give an overview of the assorted methodologies that
have been reported about the chemistry of construction of pyrimidines annulated nitrogen,
oxygen and sulphur containing five-membered heterocycles.
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Affiliation(s)
- Pradip Kumar Maji
- Department of Chemistry, Bidhan Chandra College, Asansol, Paschim Bardhaman, 713304, Rishra, West Bangal, India
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5
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Abstract
Pyrazolo[1,5-a]pyrimidines are fused N-heterocyclic systems of a pyrazole. They are considered as a key structural motif in many vital applications, such as medicinal, pharmaceuticals, pesticides, dyes and pigments. Their synthetic routes have escalated dramatically in the last decades. The current review is a recent synthetic survey of pyrazolo[ 1,5-a]pyrimidines and their applications until recently.
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Affiliation(s)
- Amal Al-Azmi
- Chemistry Department, Kuwait University, P. O. Box 5969, Safat 13060, Kuwait
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6
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Salem MA, Helal MH, Gouda MA, Abd EL-Gawad HH, Shehab MAM, El-Khalafawy A. Recent synthetic methodologies for pyrazolo[1,5-a]pyrimidine. SYNTHETIC COMMUN 2019. [DOI: 10.1080/00397911.2019.1604967] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Mohamed A. Salem
- Department of Chemistry, Faculty of Science and Arts, King Khalid University, Mohail Asir, Saudi Arabia
| | - Mohamed H. Helal
- Department of Chemistry, Faculty of Arts and Science, Northern Border University, Rafha, Saudi Arabia
| | - Moustafa A. Gouda
- Department of Chemistry, Faculty of Science and Arts, Ulla Taibah University, Medina, Saudi Arabia
| | - Hala H. Abd EL-Gawad
- Department of Chemistry, Faculty of Science and Arts, King Khalid University, Mohail Asir, Saudi Arabia
| | - Marwa A. M. Shehab
- Department of Chemistry, Faculty of Science and Arts, King Khalid University, Mohail Asir, Saudi Arabia
| | - Abeer El-Khalafawy
- Department of Chemistry, Faculty of Science, King Khalid University, Abha, Saudi Arabia
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7
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Bel Abed H, Weißing N, Schoene J, Paulus J, Sewald N, Nazaré M. Novel strategy for the preparation of 3-perfluoroalkylated-2H-indazole derivatives. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.03.051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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8
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Jismy B, Guillaumet G, Allouchi H, Akssira M, Abarbri M. Concise and Efficient Access to 5,7-Disubstituted Pyrazolo[1,5-a]pyrimidines by Pd-Catalyzed Sequential Arylation, Alkynylation and SNArReaction. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Badr Jismy
- Département de Chimie; Université François Rabelais; Laboratoire d'Infectiologie et Santé Publique (UMR 1282); équipe Recherche et Innovation en Chimie Médicinale; Parc de Grandmont 37200 Tours France
- Laboratoire de Chimie Physique et de Chimie Bioorganique; Département de Chimie Université Hassan II de Casablanca; URAC 22; 28800 Mohammedia Maroc
| | - Gérald Guillaumet
- Institut de Chimie Organique et Analytique (ICOA); Université d'Orléans; UMR CNRS 7311; BP 6759, rue de Chartres 45067 Orléans Cedex2 France
| | - Hassan Allouchi
- Département de Chimie; Université François Rabelais; Laboratoire d'Infectiologie et Santé Publique (UMR 1282); équipe Recherche et Innovation en Chimie Médicinale; Parc de Grandmont 37200 Tours France
| | - Mohamed Akssira
- Laboratoire de Chimie Physique et de Chimie Bioorganique; Département de Chimie Université Hassan II de Casablanca; URAC 22; 28800 Mohammedia Maroc
| | - Mohamed Abarbri
- Département de Chimie; Université François Rabelais; Laboratoire d'Infectiologie et Santé Publique (UMR 1282); équipe Recherche et Innovation en Chimie Médicinale; Parc de Grandmont 37200 Tours France
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9
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Ding ZC, An XM, Zeng JH, Tang ZN, Zhan ZP. Copper(I)-Catalyzed Synthesis of 4,5-Dihydropyrazolo[1,5- a
]pyrimidines via
Cascade Transformation of N
-Propargylic Sulfonylhydrazones with Sulfonyl Azides. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201700635] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Zong-Cang Ding
- Department of Chemistry, College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 People's Republic of China
| | - Xiao-Ming An
- Department of Chemistry, College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 People's Republic of China
| | - Jia-Hao Zeng
- Department of Chemistry, College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 People's Republic of China
| | - Zhao-Ning Tang
- Department of Chemistry, College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 People's Republic of China
| | - Zhuang-Ping Zhan
- Department of Chemistry, College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 People's Republic of China
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10
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Schoene J, Bel Abed H, Christmann M, Nazaré M. A straightforward approach to N -substituted-2 H -indazol-2-amines through reductive cyclization. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.03.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Castillo JC, Rosero HA, Portilla J. Simple access toward 3-halo- and 3-nitro-pyrazolo[1,5-a]pyrimidines through a one-pot sequence. RSC Adv 2017. [DOI: 10.1039/c7ra04336h] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Herein, a regioselective, time-efficient and one-pot route for the synthesis of diversely substituted 3-halo- and 3-nitropyrazolo[1,5-a]pyrimidines in good to excellent yields through a microwave-assisted process is provided.
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Affiliation(s)
- Juan-Carlos Castillo
- Bioorganic Compounds Research Group
- Department of Chemistry
- Universidad de los Andes
- Bogotá 111711
- Colombia
| | - Hernán-Alejandro Rosero
- Bioorganic Compounds Research Group
- Department of Chemistry
- Universidad de los Andes
- Bogotá 111711
- Colombia
| | - Jaime Portilla
- Bioorganic Compounds Research Group
- Department of Chemistry
- Universidad de los Andes
- Bogotá 111711
- Colombia
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12
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Golubev P, Karpova EA, Pankova AS, Sorokina M, Kuznetsov MA. Regioselective Synthesis of 7-(Trimethylsilylethynyl)pyrazolo[1,5-a]pyrimidines via Reaction of Pyrazolamines with Enynones. J Org Chem 2016; 81:11268-11275. [PMID: 27749057 DOI: 10.1021/acs.joc.6b02217] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Condensation of enynones readily available from cheap starting material with pyrazolamines provides easy access to fluorescent 7-(trimethylsilylethynyl)pyrazolo[1,5-a]pyrimidines. The reaction is straightforward, does not require the use of any additional reagents or catalysts, and can be performed without inert atmosphere. Various substituents and functional groups in both enynone and pyrazolamine are tolerated. The presented method features full regioselectivity, high isolated yields, and simplicity of both setup and product purification. Fluorescent properties of the obtained pyrazolopyrimidines were studied.
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Affiliation(s)
- Pavel Golubev
- Institute of Chemistry, Saint Petersburg State University , Universitetsky pr. 26, 198504 Saint Petersburg, Russia
| | - Ekaterina A Karpova
- Institute of Chemistry, Saint Petersburg State University , Universitetsky pr. 26, 198504 Saint Petersburg, Russia
| | - Alena S Pankova
- Institute of Chemistry, Saint Petersburg State University , Universitetsky pr. 26, 198504 Saint Petersburg, Russia
| | - Mariia Sorokina
- Institute of Chemistry, Saint Petersburg State University , Universitetsky pr. 26, 198504 Saint Petersburg, Russia
| | - Mikhail A Kuznetsov
- Institute of Chemistry, Saint Petersburg State University , Universitetsky pr. 26, 198504 Saint Petersburg, Russia
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13
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Bel Abed H, Schoene J, Christmann M, Nazaré M. Organophosphorus-mediated N-N bond formation: facile access to 3-amino-2H-indazoles. Org Biomol Chem 2016; 14:8520-8. [PMID: 27541713 DOI: 10.1039/c6ob01544a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A convenient and efficient strategy has been devised to access 3-amino-2H-indazole derivatives in two steps from readily available starting materials. The conversion of 2-nitrobenzonitriles to substituted benzamidines followed by an organophosphorus-mediated reductive cyclization and a subsequent N-N bond formation afforded 3-amino-2H-indazoles in good to excellent yields.
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Affiliation(s)
- Hassen Bel Abed
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Campus Berlin-Buch, Robert-Roessle-Str. 10, 13125 Berlin, Germany.
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14
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Sun J, Qiu JK, Jiang B, Hao WJ, Guo C, Tu SJ. I2-Catalyzed Multicomponent Reactions for Accessing Densely Functionalized Pyrazolo[1,5-a]pyrimidines and Their Disulphenylated Derivatives. J Org Chem 2016; 81:3321-8. [PMID: 26991413 DOI: 10.1021/acs.joc.6b00332] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
New I2-catalyzed multicomponent bicyclization reactions of β-ketonitriles with sulfonyl hydrazides have been established, providing a direct and metal-free access toward unreported pyrazolo[1,5-a]pyrimidin-4-ium sulfonates. The latter could be quantitatively converted into densely functionalized pyrazolo[1,5-a]pyrimidines in the presence of bases. Using sulfonyl hydrazides as a sulfenylating agent, the resulting pyrazolo[1,5-a]pyrimidines enabled I2-catalyzed unprecedented disulphenylations to access fully substituted pyrazolo[1,5-a]pyrimidines through direct C(sp(2))-H bond bifunctionalization.
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Affiliation(s)
- Jun Sun
- College of Chemistry and Molecular Engineering, Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing 211816, P. R. China
| | - Jiang-Kai Qiu
- College of Chemistry and Molecular Engineering, Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing 211816, P. R. China
| | - Bo Jiang
- School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University , Xuzhou 221116, P. R. China
| | - Wen-Juan Hao
- School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University , Xuzhou 221116, P. R. China
| | - Cheng Guo
- College of Chemistry and Molecular Engineering, Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing 211816, P. R. China
| | - Shu-Jiang Tu
- School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University , Xuzhou 221116, P. R. China
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15
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Fluorine-containing pyrazoles and their condensed derivatives: Synthesis and biological activity. J Fluor Chem 2015. [DOI: 10.1016/j.jfluchem.2015.03.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Saikia P, Gogoi S, Boruah RC. Carbon-Carbon Bond Cleavage Reaction: Synthesis of Multisubstituted Pyrazolo[1,5-a]pyrimidines. J Org Chem 2015; 80:6885-9. [PMID: 26083788 DOI: 10.1021/acs.joc.5b00933] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new carbon-carbon bond cleavage reaction was developed for the efficient synthesis of multisubstituted pyrazolo[1,5-a]pyrimidines. This base induced reaction of 1,3,5-trisubstituted pentane-1,5-diones and substituted pyrazoles afforded good yields of the pyrazolo[1,5-a]pyrimidines.
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Affiliation(s)
- Pallabi Saikia
- Medicinal Chemistry Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
| | - Sanjib Gogoi
- Medicinal Chemistry Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
| | - Romesh C Boruah
- Medicinal Chemistry Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
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17
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Bel Abed H, Mammoliti O, Bande O, Van Lommen G, Herdewijn P. Organophosphorus-catalyzed diaza-Wittig reaction: application to the synthesis of pyridazines. Org Biomol Chem 2015; 12:7159-66. [PMID: 25101802 DOI: 10.1039/c4ob01201a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The elaboration of the first organophosphorus-catalyzed diaza-Wittig reaction is reported. This catalytic reaction is applied to the synthesis of substituted pyridazine and phthalazine derivatives bearing electron-withdrawing groups with good to excellent yields from substrates containing a diazo functionality as the starting material and a phospholene oxide as the catalyst.
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Affiliation(s)
- Hassen Bel Abed
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium.
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18
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Zhang X, Song Y, Gao L, Guo X, Fan X. Highly facile and regio-selective synthesis of pyrazolo[1,5-a]pyrimidines via reactions of 1,2-allenic ketones with aminopyrazoles. Org Biomol Chem 2014; 12:2099-107. [DOI: 10.1039/c3ob42445f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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19
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Bel Abed H, Bande O, Mammoliti O, Van Lommen G, Herdewijn P. A novel and convenient strategy for the synthesis of phthalazines from an aryne precursor. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.10.075] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Bel Abed H, Mammoliti O, Bande O, Van Lommen G, Herdewijn P. Strategy for the synthesis of pyridazine heterocycles and their derivatives. J Org Chem 2013; 78:7845-58. [PMID: 23947534 DOI: 10.1021/jo400989q] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The first synthesis of novel fused pyridazines has been realized starting from 1,3-diketones involving a Diaza-Wittig reaction as a key step. A convenient strategy was elaborated to access versatile pyridazine derivatives allowing the variation of substituents at position 6 of the heterocyclic ring. In a first part, pyridazines bearing an ester group were synthesized as a model to evaluate the methodology. In a second part, an improved procedure has been used for the synthesis of pyridazines bearing a ketone group and different methods of cyclization were carried out, leading to several hitherto unknown biheterocyclic compounds. This reaction scheme represents an attractive methodology for the synthesis of novel fused pyridazine derivatives.
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Affiliation(s)
- Hassen Bel Abed
- Rega Institute for Medical Research, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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