1
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Citarella A, Vittorio S, Dank C, Ielo L. Syntheses, reactivity, and biological applications of coumarins. Front Chem 2024; 12:1362992. [PMID: 38440776 PMCID: PMC10909861 DOI: 10.3389/fchem.2024.1362992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/05/2024] [Indexed: 03/06/2024] Open
Abstract
This comprehensive review, covering 2021-2023, explores the multifaceted chemical and pharmacological potential of coumarins, emphasizing their significance as versatile natural derivatives in medicinal chemistry. The synthesis and functionalization of coumarins have advanced with innovative strategies. This enabled the incorporation of diverse functional fragments or the construction of supplementary cyclic architectures, thereby the biological and physico-chemical properties of the compounds obtained were enhanced. The unique chemical structure of coumarine facilitates binding to various targets through hydrophobic interactions pi-stacking, hydrogen bonding, and dipole-dipole interactions. Therefore, this important scaffold exhibits promising applications in uncountable fields of medicinal chemistry (e.g., neurodegenerative diseases, cancer, inflammation).
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Affiliation(s)
- Andrea Citarella
- Dipartimento di Chimica, Università degli Studi di Milano, Milano, Italy
| | - Serena Vittorio
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, Milano, Italy
| | - Christian Dank
- Institute of Organic Chemistry, University of Vienna, Vienna, Austria
| | - Laura Ielo
- Department of Chemistry, University of Turin, Turin, Italy
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2
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Citarella A, Dimasi A, Moi D, Passarella D, Scala A, Piperno A, Micale N. Recent Advances in SARS-CoV-2 Main Protease Inhibitors: From Nirmatrelvir to Future Perspectives. Biomolecules 2023; 13:1339. [PMID: 37759739 PMCID: PMC10647625 DOI: 10.3390/biom13091339] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/28/2023] [Accepted: 08/31/2023] [Indexed: 09/29/2023] Open
Abstract
The main protease (Mpro) plays a pivotal role in the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is considered a highly conserved viral target. Disruption of the catalytic activity of Mpro produces a detrimental effect on the course of the infection, making this target one of the most attractive for the treatment of COVID-19. The current success of the SARS-CoV-2 Mpro inhibitor Nirmatrelvir, the first oral drug for the treatment of severe forms of COVID-19, has further focused the attention of researchers on this important viral target, making the search for new Mpro inhibitors a thriving and exciting field for the development of antiviral drugs active against SARS-CoV-2 and related coronaviruses.
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Affiliation(s)
- Andrea Citarella
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milano, Italy; (A.D.); (D.P.)
| | - Alessandro Dimasi
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milano, Italy; (A.D.); (D.P.)
| | - Davide Moi
- Department of Chemical and Geological Sciences, University of Cagliari, S.P. 8 CA, 09042 Cagliari, Italy;
| | - Daniele Passarella
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milano, Italy; (A.D.); (D.P.)
| | - Angela Scala
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D’Alcontres 31, 98166 Messina, Italy; (A.S.); (A.P.)
| | - Anna Piperno
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D’Alcontres 31, 98166 Messina, Italy; (A.S.); (A.P.)
| | - Nicola Micale
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D’Alcontres 31, 98166 Messina, Italy; (A.S.); (A.P.)
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3
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Takeda N, Suganuma R, Yasui M, Ueda M. Synthesis of isolable β-chloroenamines from N-alkoxylactams with organometallic reagents. Org Biomol Chem 2023; 21:1435-1439. [PMID: 36649121 DOI: 10.1039/d2ob02151j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
An efficient approach to access isolable β-chloroenamines via nucleophilic addition/dehydration of α-chloro N-alkoxylactam with organolithium and Grignard reagents is reported. This approach is amenable to the synthesis of β-chloroenamines by incorporating various C(sp) and C(sp2) units, such as alkyne, aryl, and heteroaryl moieties. The sequential reaction has a broad substrate scope and can be carried out for a scalable synthesis of β-chloroenamines. Control experiments suggested that both chloro and alkoxy groups act as inductive electron-withdrawing substituents to improve the stability of the enamines.
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Affiliation(s)
- Norihiko Takeda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Riku Suganuma
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Motohiro Yasui
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Masafumi Ueda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
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4
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Liu A, Ni C, Xie Q, Hu J. Transition-Metal-Free Controllable Single and Double Difluoromethylene Formal Insertions into C-H Bonds of Aldehydes with TMSCF 2 Br. Angew Chem Int Ed Engl 2023; 62:e202217088. [PMID: 36517973 DOI: 10.1002/anie.202217088] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
We have developed a new strategy for controllable single and double difluoromethylene (CF2 ) formal insertions into C-H bonds of aldehydes with nearly full selectivity under transition-metal-free conditions. The key to the success of controllable CF2 insertions lies in the well-defined formation of 2,2-difluoroenolsilyl ether and 2,2,3,3-tetrafluorocyclopropanolsilyl ether intermediates using difluorocarbene reagent TMSCF2 Br (TMS=trimethylsilyl). These two intermediates can react with various electrophiles including proton sources and various halogenation reagents, allowing for the access to diverse arrays of ketones containing difluoromethylene (CF2 ) and tetrafluoroethylene (CF2 CF2 ) units. The first synthesis of relatively stable 2,2,3,3-tetrafluorocyclopropanolsilyl ethers has been achieved, which offers a new platform to explore other unknown chemical space.
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Affiliation(s)
- An Liu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Qiqiang Xie
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
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5
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Kornii Y, Shablykin O, Tarasiuk T, Stepaniuk O, Matvienko V, Aloshyn D, Zahorodniuk N, Sadkova IV, Mykhailiuk PK. Fluorinated Aliphatic Diazirines: Preparation, Characterization, and Model Photolabeling Studies. J Org Chem 2023; 88:1-17. [PMID: 36399052 DOI: 10.1021/acs.joc.2c02262] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The previously unknown difluoromethyl diazirines and the previously neglected trifluoromethyl-aliphatic diazirines were synthesized and characterized. Model photolabeling experiments and biological studies showed that these compounds could indeed be used as photoaffinity labels.
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Affiliation(s)
- Yurii Kornii
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine.,V.P.Kukhar Institute of Bioorganic Chemistry and Petrochemistry NAS of Ukraine, Kyiv 02094, Ukraine
| | - Oleg Shablykin
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine.,V.P.Kukhar Institute of Bioorganic Chemistry and Petrochemistry NAS of Ukraine, Kyiv 02094, Ukraine
| | - Taras Tarasiuk
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine
| | | | | | - Danylo Aloshyn
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine.,Bienta, Chervonotkatska 78, Kyiv 02094, Ukraine
| | - Nataliia Zahorodniuk
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine.,Bienta, Chervonotkatska 78, Kyiv 02094, Ukraine
| | - Iryna V Sadkova
- Enamine Ltd., Oleksandra Matrosova Street 23, Kyiv 01103, Ukraine
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6
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Citarella A, Amenta A, Passarella D, Micale N. Cyrene: A Green Solvent for the Synthesis of Bioactive Molecules and Functional Biomaterials. Int J Mol Sci 2022; 23:ijms232415960. [PMID: 36555601 PMCID: PMC9783252 DOI: 10.3390/ijms232415960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 12/10/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
In the panorama of sustainable chemistry, the use of green solvents is increasingly emerging for the optimization of more eco-friendly processes which look to a future of biocompatibility and recycling. The green solvent Cyrene, obtained from biomass via a two-step synthesis, is increasingly being introduced as the solvent of choice for the development of green synthetic transformations and for the production of biomaterials, thanks to its interesting biocompatibility, non-toxic and non-mutagenic properties. Our review offers an overview of the most important organic reactions that have been investigated to date in Cyrene as a medium, in particular focusing on those that could potentially lead to the formation of relevant chemical bonds in bioactive molecules. On the other hand, a description of the employment of Cyrene in the production of biomaterials has also been taken into consideration, providing a point-by-point overview of the use of Cyrene to date in the aforementioned fields.
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Affiliation(s)
- Andrea Citarella
- Department of Chemistry, University of Milan, Via Golgi 19, I-20133 Milano, Italy
| | - Arianna Amenta
- Department of Chemistry, University of Milan, Via Golgi 19, I-20133 Milano, Italy
| | - Daniele Passarella
- Department of Chemistry, University of Milan, Via Golgi 19, I-20133 Milano, Italy
| | - Nicola Micale
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D’Alcontres 31, I-98166 Messina, Italy
- Correspondence:
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7
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Regioselective transformation of terminal and internal alkynes into α,α-difluoro ketones under mild conditions. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.154197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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8
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Novel Class of Proteasome Inhibitors: In Silico and In Vitro Evaluation of Diverse Chloro(trifluoromethyl)aziridines. Int J Mol Sci 2022; 23:ijms232012363. [PMID: 36293216 PMCID: PMC9603864 DOI: 10.3390/ijms232012363] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 09/30/2022] [Accepted: 10/11/2022] [Indexed: 01/24/2023] Open
Abstract
The ubiquitin-proteasome pathway (UPP) is the major proteolytic system in the cytosol and nucleus of all eukaryotic cells. The role of proteasome inhibitors (PIs) as critical agents for regulating cancer cell death has been established. Aziridine derivatives are well-known alkylating agents employed against cancer. However, to the best of our knowledge, aziridine derivatives showing inhibitory activity towards proteasome have never been described before. Herein we report a new class of selective and nonPIs bearing an aziridine ring as a core structure. In vitro cell-based assays (two leukemia cell lines) also displayed anti-proliferative activity for some compounds. In silico studies indicated non-covalent binding mode and drug-likeness for these derivatives. Taken together, these results are promising for developing more potent PIs.
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9
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Kitano J, Nishii Y, Miura M. Selective Synthesis of C4-Functionalized Benzofurans by Rhodium-Catalyzed Vinylene Transfer: Computational Study on the Cyclopentadienyl Ligand. Org Lett 2022; 24:5679-5683. [PMID: 35900136 DOI: 10.1021/acs.orglett.2c02030] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Benzofuran is a privileged structure in many bioactive compounds; however, the controlled synthesis of C2,C3-nonsubstituted benzofurans has been scarce. In particular, cumbersome multistep processes are inevitable for the most inaccessible C4-substituted isomers. Herein, we report a Rh-catalyzed direct vinylene annulation of readily available m-salicylic acid derivatives with vinylene carbonate to achieve selective construction of C4-substituted benzofurans. The Weinreb amide directing group facilitated the following product derivatization. The reaction mechanism was investigated by DFT calculations.
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Affiliation(s)
- Junya Kitano
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yuji Nishii
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Masahiro Miura
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
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10
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Senatore R, Malik M, Pace V. Fluoroiodomethane: A CH2F‐Moiety Delivering Agent Suitable for Nucleophilic‐, Electrophilic‐ and Radical‐Harnessed Operations. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Miele M, Castoldi L, Simeone X, Holzer W, Pace V. Straightforward synthesis of bench-stable heteroatom-centered difluoromethylated entities via controlled nucleophilic transfer from activated TMSCHF 2. Chem Commun (Camb) 2022; 58:5761-5764. [PMID: 35450981 DOI: 10.1039/d2cc00886f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The commercially available and experimentally convenient (bp 65 °C) difluoromethyltrimethylsilane (TMSCHF2) is proposed as a valuable difluoromethylating transfer reagent for delivering the CHF2 moiety to various heteroatom-based electrophiles. Upon activation with an alkoxide, a conceptually intuitive nucleophilic displacement directly furnishes in high yields the bench-stable analogues.
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Affiliation(s)
- Margherita Miele
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14 1090 Vienna, Austria.
| | - Laura Castoldi
- University of Milano - Department of Pharmaceutical Sciences, Via Golgi 19, 20133 Milano, Italy
| | - Xenia Simeone
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14 1090 Vienna, Austria.
| | - Wolfgang Holzer
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14 1090 Vienna, Austria.
| | - Vittorio Pace
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14 1090 Vienna, Austria. .,University of Torino - Department of Chemistry, Via Giuria 7, 10125 Torino, Italy
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12
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Duan J, Choy PY, Gan KB, Kwong FY. N-Difluoromethylation of N-pyridyl-substituted anilines with ethyl bromodifluoroacetate. Org Biomol Chem 2022; 20:1883-1887. [PMID: 35171189 DOI: 10.1039/d2ob00119e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general protocol for N-difluoromethylation of aniline derivatives is developed. Commercially available ethyl bromodifluoroacetate serves as a difluorocarbene source in the presence of a base. This carbene surrogate is attractive owing to its favorable stability, environmental friendliness and inexpensiveness. This reaction system features notable operational simplicity (bench top-grade solvents can be used without any pre-drying and do not require inert atmosphere protection). A wide range of functional groups in aniline derivatives are well-tolerated, and good-to-excellent product yields are generally obtained.
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Affiliation(s)
- Jindian Duan
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China.,College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
| | - Pui Ying Choy
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P.R. China.
| | - Kin Boon Gan
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P.R. China.
| | - Fuk Yee Kwong
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China.,Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P.R. China.
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13
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Zhu W, Xi H, Jiao W, Huang L, Wang L, Wu J. Difunctionalization of gem-Difluoroalkenes via Photoredox Catalysis: Synthesis of Diverse α,α-Difluoromethyl-β-alkoxysulfones. Org Lett 2022; 24:720-725. [PMID: 34981944 DOI: 10.1021/acs.orglett.1c04165] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Visible-light-promoted alkoxysulfonylation of gem-difluoroalkenes using sulfonyl chlorides and alcohols has been developed. The reaction exhibits a relatively broad substrate scope with excellent functional group compatibility. This synthesis method includes an atom transfer radical addition-like process. The products can be used as platform molecules for further modification.
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Affiliation(s)
- Wenjuan Zhu
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Hui Xi
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, P. R. China
| | - Wenyang Jiao
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Lihua Huang
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Lianjie Wang
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Junliang Wu
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
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14
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Zhang R, Ma R, Fu Q, Chen R, Wang Z, Wang L, Ma Y. Selective electrophilic di- and mono-fluorinations for the synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones by Selectfluor-triggered multi-component reaction. Org Chem Front 2022. [DOI: 10.1039/d1qo01728d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A simple and efficient domino protocol for the selective synthesis of 4-difluoromethyl and 4-fluoromethyl quinazolin(thi)ones was established from readily available 2-aminoacetophenones and iso(thio)cyanates mediated by Selectfluor. The reaction outcomes are...
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15
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Helesbeux JJ, Carro L, McCarthy FO, Moreira VM, Giuntini F, O’Boyle N, Matthews SE, Bayraktar G, Bertrand S, Rochais C, Marchand P. 29th Annual GP2A Medicinal Chemistry Conference. Pharmaceuticals (Basel) 2021; 14:ph14121278. [PMID: 34959677 PMCID: PMC8708472 DOI: 10.3390/ph14121278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 11/18/2021] [Indexed: 11/16/2022] Open
Abstract
The 29th Annual GP2A (Group for the Promotion of Pharmaceutical chemistry in Academia) Conference was a virtual event this year due to the COVID-19 pandemic and spanned three days from Wednesday 25 to Friday 27 August 2021. The meeting brought together an international delegation of researchers with interests in medicinal chemistry and interfacing disciplines. Abstracts of keynote lectures given by the 10 invited speakers, along with those of the 8 young researcher talks and the 50 flash presentation posters, are included in this report. Like previous editions, the conference was a real success, with high-level scientific discussions on cutting-edge advances in the fields of pharmaceutical chemistry.
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Affiliation(s)
| | - Laura Carro
- School of Pharmacy, University College London, London WC1N 1AX, UK;
| | - Florence O. McCarthy
- School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork, College Road, T12 K8AF Cork, Ireland;
| | - Vânia M. Moreira
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal;
- Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504 Coimbra, Portugal
| | - Francesca Giuntini
- School of Pharmacy and Biomolecular Sciences, Byrom Street Campus, Liverpool John Moores University, Liverpool L3 3AF, UK;
| | - Niamh O’Boyle
- School of Pharmacy and Pharmaceutical Sciences, Panoz Institute, Trinity College Dublin, D02 R590 Dublin, Ireland;
| | - Susan E. Matthews
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK;
| | - Gülşah Bayraktar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ege University, Izmir 35100, Turkey;
| | - Samuel Bertrand
- Institut des Substances et Organismes de la Mer, ISOmer, Nantes Université, UR 2160, F-44000 Nantes, France;
| | - Christophe Rochais
- UNICAEN, CERMN (Centre d’Etudes et de Recherche sur le Médicament de Normandie), Normandie Univ., F-14032 Caen, France;
| | - Pascal Marchand
- Cibles et Médicaments des Infections et du Cancer, IICiMed, Nantes Université, UR 1155, F-44000 Nantes, France
- Correspondence: ; Tel.: +33-253-009-155
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16
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Panda S, Poudel TN, Hegde P, Aldrich CC. Innovative Strategies for the Construction of Diverse 1'-Modified C-Nucleoside Derivatives. J Org Chem 2021; 86:16625-16640. [PMID: 34756029 DOI: 10.1021/acs.joc.1c01920] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Modified C-nucleosides have proven to be enormously successful as chemical probes to understand fundamental biological processes and as small-molecule drugs for cancer and infectious diseases. Historically, the modification of the glycosyl unit has focused on the 2'-, 3'-, and 4'-positions as well as the ribofuranosyl ring oxygen. By contrast, the 1'-position has rarely been studied due to the labile nature of the anomeric position. However, the improved chemical stability of C-nucleosides allows the modification of the 1'-position with substituents not found in conventional N-nucleosides. Herein, we disclose new chemistry for the installation of diverse substituents at the 1'-position of C-nucleosides, including alkyl, alkenyl, difluoromethyl, and fluoromethyl substituents, using the 4-amino-7-(1'-hydroxy-d-ribofuranosyl)pyrrolo[2,1-f][1,2,4]triazine scaffold as a representative purine nucleoside mimetic.
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Affiliation(s)
- Subhankar Panda
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Tej Narayan Poudel
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Pooja Hegde
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Courtney C Aldrich
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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17
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Ispizua-Rodriguez X, Munoz SB, Krishnamurti V, Mathew T, Prakash GKS. Direct Synthesis of Tri-/Difluoromethyl Ketones from Carboxylic Acids by Cross-Coupling with Acyloxyphosphonium Ions. Chemistry 2021; 27:15908-15913. [PMID: 34469605 DOI: 10.1002/chem.202102854] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Indexed: 11/09/2022]
Abstract
A simple and straightforward approach to the synthesis of trifluoromethyl and difluoromethyl ketones from widely available carboxylic acids is disclosed. The transformation utilizes an acyloxyphosphonium ion as the active electrophile, conveniently generated in situ from the carboxylic acid substrate by using commodity chemicals. The utility of the reaction system is exemplified by its chemoselectivity, with tolerance to a variety of important functional groups. The late-stage functionalization of carboxylic acid active pharmaceutical ingredients and pharmaceutically relevant compounds is also discussed.
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Affiliation(s)
- Xanath Ispizua-Rodriguez
- Department of Chemistry, Loker Hydrocarbon Research Institute, University of Southern California, 837 Bloom Walk, Los Angeles, CA-90089-1661, USA
| | - Socrates B Munoz
- Department of Chemistry, Kansas State University, 322 CBC Bldg, Manhattan, KS66506-0401, USA
| | - Vinayak Krishnamurti
- Department of Chemistry, Loker Hydrocarbon Research Institute, University of Southern California, 837 Bloom Walk, Los Angeles, CA-90089-1661, USA
| | - Thomas Mathew
- Department of Chemistry, Loker Hydrocarbon Research Institute, University of Southern California, 837 Bloom Walk, Los Angeles, CA-90089-1661, USA
| | - G K S Prakash
- Department of Chemistry, Loker Hydrocarbon Research Institute, University of Southern California, 837 Bloom Walk, Los Angeles, CA-90089-1661, USA
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18
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Box JR, Atkins AP, Lennox AJJ. Direct electrochemical hydrodefluorination of trifluoromethylketones enabled by non-protic conditions. Chem Sci 2021; 12:10252-10258. [PMID: 34377412 PMCID: PMC8336478 DOI: 10.1039/d1sc01574e] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/22/2021] [Indexed: 12/20/2022] Open
Abstract
CF2H groups are unique due to the combination of their lipophilic and hydrogen bonding properties. The strength of H-bonding is determined by the group to which it is appended. Several functional groups have been explored in this context including O, S, SO and SO2 to tune the intermolecular interaction. Difluoromethyl ketones are under-studied in this context, without a broadly accessible method for their preparation. Herein, we describe the development of an electrochemical hydrodefluorination of readily accessible trifluoromethylketones. The single-step reaction at deeply reductive potentials is uniquely amenable to challenging electron-rich substrates and reductively sensitive functionality. Key to this success is the use of non-protic conditions enabled by an ammonium salt that serves as a reductively stable, masked proton source. Analysis of their H-bonding has revealed difluoromethyl ketones to be potentially highly useful dual H-bond donor/acceptor moieties. The electrochemical hydrodefluorination of trifluoromethylketones under non-protic conditions make this single-step reaction at deeply reductive potentials uniquely amenable to challenging electron-rich substrates and reductively sensitive functionalities.![]()
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Affiliation(s)
- John R Box
- School of Chemistry, University of Bristol Cantock's Close Bristol BS8 1TS UK
| | - Alexander P Atkins
- School of Chemistry, University of Bristol Cantock's Close Bristol BS8 1TS UK
| | - Alastair J J Lennox
- School of Chemistry, University of Bristol Cantock's Close Bristol BS8 1TS UK
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19
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Rahman MM, Szostak M. Synthesis of Sulfoxonium Ylides from Amides by Selective N-C(O) Activation. Org Lett 2021; 23:4818-4822. [PMID: 34096314 DOI: 10.1021/acs.orglett.1c01535] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The direct synthesis of sulfoxonium ylides from amides by selective N-C(O) cleavage is presented. The reaction proceeds through the nucleophilic addition of dimethylsulfoxonium methylide to the amide bond in acyclic twisted amides under exceedingly mild room temperature conditions. A variety of amides can be employed, and the protocol can be applied to the late-stage derivatization of pharmaceuticals. Mechanistic studies outline the relative order of reactivity of amides.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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20
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Citarella A, Scala A, Piperno A, Micale N. SARS-CoV-2 M pro: A Potential Target for Peptidomimetics and Small-Molecule Inhibitors. Biomolecules 2021; 11:607. [PMID: 33921886 PMCID: PMC8073203 DOI: 10.3390/biom11040607] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/13/2021] [Accepted: 04/16/2021] [Indexed: 12/17/2022] Open
Abstract
The uncontrolled spread of the COVID-19 pandemic caused by the new coronavirus SARS-CoV-2 during 2020-2021 is one of the most devastating events in the history, with remarkable impacts on the health, economic systems, and habits of the entire world population. While some effective vaccines are nowadays approved and extensively administered, the long-term efficacy and safety of this line of intervention is constantly under debate as coronaviruses rapidly mutate and several SARS-CoV-2 variants have been already identified worldwide. Then, the WHO's main recommendations to prevent severe clinical complications by COVID-19 are still essentially based on social distancing and limitation of human interactions, therefore the identification of new target-based drugs became a priority. Several strategies have been proposed to counteract such viral infection, including the repurposing of FDA already approved for the treatment of HIV, HCV, and EBOLA, inter alia. Among the evaluated compounds, inhibitors of the main protease of the coronavirus (Mpro) are becoming more and more promising candidates. Mpro holds a pivotal role during the onset of the infection and its function is intimately related with the beginning of viral replication. The interruption of its catalytic activity could represent a relevant strategy for the development of anti-coronavirus drugs. SARS-CoV-2 Mpro is a peculiar cysteine protease of the coronavirus family, responsible for the replication and infectivity of the parasite. This review offers a detailed analysis of the repurposed drugs and the newly synthesized molecules developed to date for the treatment of COVID-19 which share the common feature of targeting SARS-CoV-2 Mpro, as well as a brief overview of the main enzymatic and cell-based assays to efficaciously screen such compounds.
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Affiliation(s)
| | | | | | - Nicola Micale
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy; (A.C.); (A.S.); (A.P.)
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21
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Li G, Szostak M. Synthesis of biaryl ketones by arylation of Weinreb amides with functionalized Grignard reagents under thermodynamic control vs. kinetic control of N,N-Boc 2-amides. Org Biomol Chem 2021; 18:3827-3831. [PMID: 32396595 DOI: 10.1039/d0ob00813c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A highly efficient method for chemoselective synthesis of biaryl ketones by arylation of Weinreb amides (N-methoxy-N-methylamides) with functionalized Grignard reagents is reported. This protocol offers rapid entry to functionalized biaryl ketones after Mg/halide exchange with i-PrMgCl·LiCl under operationally-simple and practical reaction conditions. The scope of the method is highlighted in >40 examples, including bioactive compounds and pharmaceutical derivatives. Collectively, this transition-metal-free approach offers a major advantage over the recently established cross-coupling of amides by oxidative addition of N-C(O) bonds. Considering the utility of amide acylation reactions in modern synthesis, we expect that this method will be of broad interest.
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Affiliation(s)
- Guangchen Li
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
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22
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Touqeer S, Ielo L, Miele M, Urban E, Holzer W, Pace V. Direct and straightforward transfer of C1 functionalized synthons to phosphorous electrophiles for accessing gem-P-containing methanes. Org Biomol Chem 2021; 19:2425-2429. [PMID: 33666635 DOI: 10.1039/d1ob00273b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The direct transfer of different α-substituted methyllithium reagents to chlorinated phosphorous electrophiles of diverse oxidation state (phosphates, phosphine oxides and phosphines) is proposed as an effective strategy to synthesize geminal P-containing methanes. The methodology relies on the efficient nucleophilic substitution conducted on the P-chlorine linkage. Uniformly high yields are observed regardless the specific nature of the carbanion employed: once established the conditions for generating the competent nucleophile (LiCH2Hal, LiCHHal2, LiCH2CN, LiCH2SeR etc.) the homologated compounds are obtained via a single operation. Some P-containing formal carbanions have been evaluated in transferring processes, including the carbonyl-difluoromethylation of the opioid agent Hydrocodone.
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Affiliation(s)
- Saad Touqeer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, Vienna, Austria
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23
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Xie Y, Hu T, Zhang Y, Wei D, Zheng W, Zhu F, Tian G, Aisa HA, Shen J. Weinreb Amide Approach to the Practical Synthesis of a Key Remdesivir Intermediate. J Org Chem 2021; 86:5065-5072. [PMID: 33733767 DOI: 10.1021/acs.joc.0c02986] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Currently, remdesivir is the first and only FDA-approved antiviral drug for COVID-19 treatment. Adequate supplies of remdesivir are highly warranted to cope with this global public health crisis. Herein, we report a Weinreb amide approach for preparing the key intermediate of remdesivir in the glycosylation step where overaddition side reactions are eliminated. Starting from 2,3,5-tri-O-benzyl-d-ribonolactone, the preferred route consisting of three sequential steps (Weinreb amidation, O-TMS protection, and Grignard addition) enables a high-yield (65%) synthesis of this intermediate at a kilogram scale. In particular, the undesirable PhMgCl used in previous methods was successfully replaced by MeMgBr. This approach proved to be suitable for the scalable production of the key remdesivir intermediate.
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Affiliation(s)
- Yuanchao Xie
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, P. R. China
| | - Tianwen Hu
- Key Laboratory of Plant Resources and Chemistry in Arid Regions, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, South Beijing Road 40-1, Urumqi, Xinjiang 830011, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Yan Zhang
- Key Laboratory of Plant Resources and Chemistry in Arid Regions, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, South Beijing Road 40-1, Urumqi, Xinjiang 830011, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Daibao Wei
- Key Laboratory of Plant Resources and Chemistry in Arid Regions, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, South Beijing Road 40-1, Urumqi, Xinjiang 830011, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Wei Zheng
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Fuqiang Zhu
- Topharman Shanghai Co., Ltd., No. 388 Jialilue Road, Zhangjiang Hitech Park, Shanghai 201203, P. R. China
| | - Guanghui Tian
- Topharman Shanghai Co., Ltd., No. 388 Jialilue Road, Zhangjiang Hitech Park, Shanghai 201203, P. R. China
| | - Haji A Aisa
- Key Laboratory of Plant Resources and Chemistry in Arid Regions, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, South Beijing Road 40-1, Urumqi, Xinjiang 830011, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Jingshan Shen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, P. R. China.,University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
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24
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Ielo L, Miele M, Pillari V, Senatore R, Mirabile S, Gitto R, Holzer W, Alcántara AR, Pace V. Taking advantage of lithium monohalocarbenoid intrinsic α-elimination in 2-MeTHF: controlled epoxide ring-opening en route to halohydrins. Org Biomol Chem 2021; 19:2038-2043. [PMID: 33599644 DOI: 10.1039/d0ob02407d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The intrinsic degradative α-elimination of Li carbenoids somehow complicates their use in synthesis as C1-synthons. Nevertheless, we herein report how boosting such an α-elimination is a straightforward strategy for accomplishing controlled ring-opening of epoxides to furnish the corresponding β-halohydrins. Crucial for the development of the method is the use of the eco-friendly solvent 2-MeTHF, which forces the degradation of the incipient monohalolithium, due to the very limited stabilizing effect of this solvent on the chemical integrity of the carbenoid. With this approach, high yields of the targeted compounds are consistently obtained under very high regiocontrol and, despite the basic nature of the reagents, no racemization of enantiopure materials is observed.
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Affiliation(s)
- Laura Ielo
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria. and University of Turin - Department of Chemistry, Via P. Giuria 7, 10125, Turin, Italy
| | - Margherita Miele
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Veronica Pillari
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Raffaele Senatore
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Salvatore Mirabile
- University of Messina - Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, Viale Palatucci, 13, 98168 Messina, Italy
| | - Rosaria Gitto
- University of Messina - Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, Viale Palatucci, 13, 98168 Messina, Italy
| | - Wolfgang Holzer
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Andrés R Alcántara
- Complutense University of Madrid - Department of Chemistry in Pharmaceutical Sciences, Plaza de Ramón y Cajal, s/n, Madrid, Spain.
| | - Vittorio Pace
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria. and University of Turin - Department of Chemistry, Via P. Giuria 7, 10125, Turin, Italy
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25
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Day DP, Vargas JAM, Burtoloso ACB. Synthetic Routes Towards the Synthesis of Geminal α-Difunctionalized Ketones. CHEM REC 2021; 21:2837-2854. [PMID: 33533538 DOI: 10.1002/tcr.202000176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/11/2021] [Indexed: 12/25/2022]
Abstract
The importance of gem-difunctionalized ketones is represented by their broad applications across chemical boundaries over recent years. The interesting reactivities that this class of compounds possess have made them ideal building blocks to access high-value organic molecules. Furthermore, the gem-difunctionalized ketone moiety has featured in numerous bioactive molecules. For these reasons, a plethora of routes to access such significant molecules have been developed by research groups worldwide - this account looks at delineating the synthesis of gem-difunctionalized ketones from carbonyl substrates, diazo compounds, sulfur ylides and alkynyl reactants.
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Affiliation(s)
- David P Day
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brasil
| | - Jorge A M Vargas
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brasil.,Facultad de Ciencias Básicas, Universidad Santiago de Cali, Calle 5 # 62-00 Campus Pampalinda, Santiago de Cali, Colombia
| | - Antonio C B Burtoloso
- Instituto de Química de São Carlos, Universidade de São Paulo, CEP 13560-970, São Carlos, SP, Brasil
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26
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Pseudo-Dipeptide Bearing α,α-Difluoromethyl Ketone Moiety as Electrophilic Warhead with Activity against Coronaviruses. Int J Mol Sci 2021; 22:ijms22031398. [PMID: 33573283 PMCID: PMC7866854 DOI: 10.3390/ijms22031398] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 01/26/2021] [Indexed: 12/18/2022] Open
Abstract
The synthesis of α-fluorinated methyl ketones has always been challenging. New methods based on the homologation chemistry via nucleophilic halocarbenoid transfer, carried out recently in our labs, allowed us to design and synthesize a target-directed dipeptidyl α,α-difluoromethyl ketone (DFMK) 8 as a potential antiviral agent with activity against human coronaviruses. The ability of the newly synthesized compound to inhibit viral replication was evaluated by a viral cytopathic effect (CPE)-based assay performed on MCR5 cells infected with one of the four human coronaviruses associated with respiratory distress, i.e., hCoV-229E, showing antiproliferative activity in the micromolar range (EC50 = 12.9 ± 1.22 µM), with a very low cytotoxicity profile (CC50 = 170 ± 3.79 µM, 307 ± 11.63 µM, and 174 ± 7.6 µM for A549, human embryonic lung fibroblasts (HELFs), and MRC5 cells, respectively). Docking and molecular dynamics simulations studies indicated that 8 efficaciously binds to the intended target hCoV-229E main protease (Mpro). Moreover, due to the high similarity between hCoV-229E Mpro and SARS-CoV-2 Mpro, we also performed the in silico analysis towards the second target, which showed results comparable to those obtained for hCoV-229E Mpro and promising in terms of energy of binding and docking pose.
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27
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Alam MN, Dash SR, Mukherjee A, Pandole S, Marelli UK, Vanka K, Maity P. [1,3]-Claisen Rearrangement via Removable Functional Group Mediated Radical Stabilization. Org Lett 2021; 23:890-895. [PMID: 33443431 DOI: 10.1021/acs.orglett.0c04109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A thermal O-to-C [1,3]-rearrangement of α-hydroxy acid derived enol ethers was achieved under mild conditions. The 2-aminothiophenol protection of carboxylic acids facilitates formation of the [1,3] precursor and its thermal rearrangement via stabilization of a radical intermediate. Experimental and theoretical evidence for dissociative radical pair formation, its captodative stability via aminothiophenol, and a unique solvent effect are presented. The aminothiophenol was deprotected from rearrangement products as well as after derivatization to useful synthons.
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Affiliation(s)
- Md Nirshad Alam
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Soumya Ranjan Dash
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.,Physical and Material Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Anirban Mukherjee
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Satish Pandole
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Udaya Kiran Marelli
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Kumar Vanka
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.,Physical and Material Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Pradip Maity
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
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28
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Sap JBI, Meyer CF, Straathof NJW, Iwumene N, am Ende CW, Trabanco AA, Gouverneur V. Late-stage difluoromethylation: concepts, developments and perspective. Chem Soc Rev 2021; 50:8214-8247. [DOI: 10.1039/d1cs00360g] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review describes the conceptual advances that have led to the multiple difluoromethylation processes making use of well-defined CF2H sources.
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Affiliation(s)
- Jeroen B. I. Sap
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Claudio F. Meyer
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Natan J. W. Straathof
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Ndidi Iwumene
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Christopher W. am Ende
- Pfizer Inc
- Medicine Design, Eastern Point Road, Groton, Connecticut 06340, and 1 Portland Street
- Cambridge
- USA
| | | | - Véronique Gouverneur
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
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29
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Miele M, Pace V. (Difluoromethyl)trimethylsilane (TMSCHF2): A Useful Difluoromethylating Nucleophilic Source. Aust J Chem 2021. [DOI: 10.1071/ch21045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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30
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Senatore R, Malik M, Touqeer S, Listro R, Collina S, Holzer W, Pace V. Straightforward and direct access to β-seleno- amines and sulfonylamides via the controlled addition of phenylselenomethyllithium (LiCH2SePh) to imines. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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31
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Shimada N, Takahashi N, Ohse N, Koshizuka M, Makino K. Synthesis of Weinreb amides using diboronic acid anhydride-catalyzed dehydrative amidation of carboxylic acids. Chem Commun (Camb) 2020; 56:13145-13148. [PMID: 33007055 DOI: 10.1039/d0cc05630h] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The first successful example of the direct synthesis of Weinreb amides using catalytic hydroxy-directed dehydrative amidation of carboxylic acids using the diboronic acid anhydride catalyst is described. The methodology is applicable to the concise syntheses of eight α-hydroxyketone natural products, namely, sattabacin, 4-hydroxy sattabacin, kurasoins A and B, soraphinols A and B, and circumcins B and C.
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Affiliation(s)
- Naoyuki Shimada
- Department of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minatao-ku, Tokyo 108-8641, Japan.
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32
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Morita K, Murai K, Arisawa M, Fujioka H. Selective Reduction of α,β-Unsaturated Weinreb Amides in the Presence of α,β-Unsaturated Esters. Chem Pharm Bull (Tokyo) 2020; 68:1100-1103. [PMID: 33132377 DOI: 10.1248/cpb.c20-00545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
α,β-Unsaturated esters were selectively protected in situ in the presence of α,β-unsaturated Weinreb amides using PEt3 and trimethylsilyl trifluoromethanesulfonate (TMSOTf) in toluene under reflux. Diisobutylaluminium hydride (DIBAL-H) reduction of the mixture followed by tetra-n-butylammonium fluoride (TBAF) treatment produced α,β-unsaturated aldehydes in good yields along with the recovered α,β-unsaturated esters.
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Affiliation(s)
- Kenta Morita
- Graduate School of Pharmaceutical Sciences, Osaka University
| | - Kenichi Murai
- Graduate School of Pharmaceutical Sciences, Osaka University
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33
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Touqeer S, Senatore R, Malik M, Urban E, Pace V. Modular and Chemoselective Strategy for Accessing (Distinct) α,α‐Dihaloketones from Weinreb Amides and Dihalomethyllithiums. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202001106] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Saad Touqeer
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Raffaele Senatore
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Monika Malik
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Ernst Urban
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Vittorio Pace
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
- University of Turin Department of Chemistry Via P. Giuria 7 10125 Turin Italy
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34
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Miele M, Citarella A, Langer T, Urban E, Zehl M, Holzer W, Ielo L, Pace V. Chemoselective Homologation-Deoxygenation Strategy Enabling the Direct Conversion of Carbonyls into ( n+1)-Halomethyl-Alkanes. Org Lett 2020; 22:7629-7634. [PMID: 32910659 PMCID: PMC8011987 DOI: 10.1021/acs.orglett.0c02831] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
The sequential installation
of a carbenoid and a hydride into a
carbonyl, furnishing halomethyl alkyl derivatives, is reported. Despite
the employment of carbenoids as nucleophiles in reactions with carbon-centered
electrophiles, sp3-type alkyl halides remain elusive materials
for selective one-carbon homologations. Our tactic levers on using
carbonyls as starting materials and enables uniformly high yields
and chemocontrol. The tactic is flexible and is not limited to carbenoids.
Also, diverse carbanion-like species can act as nucleophiles, thus
making it of general applicability.
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Affiliation(s)
- Margherita Miele
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Andrea Citarella
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria.,Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno D'Alcontres, 31, 98166 Messina, Italy
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Ernst Urban
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Martin Zehl
- Faculty of Chemistry - Department of Analytical Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Laura Ielo
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria.,Department of Chemistry, University of Turin, Via P. Giuria 7, 10125 Turin, Italy
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35
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Ielo L, Castoldi L, Touqeer S, Lombino J, Roller A, Prandi C, Holzer W, Pace V. Halogen‐Imparted Reactivity in Lithium Carbenoid Mediated Homologations of Imine Surrogates: Direct Assembly of bis‐Trifluoromethyl‐β‐Diketiminates and the Dual Role of LiCH
2
I. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007954] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Laura Ielo
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Laura Castoldi
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Saad Touqeer
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Jessica Lombino
- Fondazione Ri.MED Via Bandiera 11 90133 Palermo Italy
- University of Palermo Department STEBICEF Via Archirafi 32 90123 Palermo Italy
| | - Alexander Roller
- University of Vienna X-Ray Structure Analysis Center Waehringerstrasse 42 1090 Vienna Austria
| | - Cristina Prandi
- University of Turin Department of Chemistry Via P. Giuria 7 10125 Turin Italy
| | - Wolfgang Holzer
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Vittorio Pace
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
- University of Turin Department of Chemistry Via P. Giuria 7 10125 Turin Italy
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Ielo L, Castoldi L, Touqeer S, Lombino J, Roller A, Prandi C, Holzer W, Pace V. Halogen‐Imparted Reactivity in Lithium Carbenoid Mediated Homologations of Imine Surrogates: Direct Assembly of bis‐Trifluoromethyl‐β‐Diketiminates and the Dual Role of LiCH
2
I. Angew Chem Int Ed Engl 2020; 59:20852-20857. [DOI: 10.1002/anie.202007954] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/17/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Laura Ielo
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Laura Castoldi
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Saad Touqeer
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Jessica Lombino
- Fondazione Ri.MED Via Bandiera 11 90133 Palermo Italy
- University of Palermo Department STEBICEF Via Archirafi 32 90123 Palermo Italy
| | - Alexander Roller
- University of Vienna X-Ray Structure Analysis Center Waehringerstrasse 42 1090 Vienna Austria
| | - Cristina Prandi
- University of Turin Department of Chemistry Via P. Giuria 7 10125 Turin Italy
| | - Wolfgang Holzer
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
| | - Vittorio Pace
- University of Vienna Department of Pharmaceutical Chemistry Althanstrasse 14 1090 Vienna Austria
- University of Turin Department of Chemistry Via P. Giuria 7 10125 Turin Italy
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37
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Peptidyl Fluoromethyl Ketones and Their Applications in Medicinal Chemistry. Molecules 2020; 25:molecules25174031. [PMID: 32899354 PMCID: PMC7504820 DOI: 10.3390/molecules25174031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/29/2022] Open
Abstract
Peptidyl fluoromethyl ketones occupy a pivotal role in the current scenario of synthetic chemistry, thanks to their numerous applications as inhibitors of hydrolytic enzymes. The insertion of one or more fluorine atoms adjacent to a C-terminal ketone moiety greatly modifies the physicochemical properties of the overall substrate, especially by increasing the reactivity of this functionalized carbonyl group toward nucleophiles. The main application of these peptidyl α-fluorinated ketones in medicinal chemistry relies in their ability to strongly and selectively inhibit serine and cysteine proteases. These compounds can be used as probes to study the proteolytic activity of the aforementioned proteases and to elucidate their role in the insurgence and progress on several diseases. Likewise, if the fluorinated methyl ketone moiety is suitably connected to a peptidic backbone, it may confer to the resulting structure an excellent substrate peculiarity and the possibility of being recognized by a specific subclass of human or pathogenic proteases. Therefore, peptidyl fluoromethyl ketones are also currently highly exploited for the target-based design of compounds for the treatment of topical diseases such as various types of cancer and viral infections.
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38
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Gaspa S, Farina A, Tilocca M, Porcheddu A, Pisano L, Carraro M, Azzena U, De Luca L. Visible-Light Photoredox-Catalyzed Amidation of Benzylic Alcohols. J Org Chem 2020; 85:11679-11687. [PMID: 32662268 PMCID: PMC8009506 DOI: 10.1021/acs.joc.0c01320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A new photocatalyzed route to amides from alcohols and amines mediated by visible light is presented. The reaction is carried out in ethyl acetate as a solvent. Ethyl acetate can be defined a green and bio-based solvent. The starting materials such as the energy source are easily available, stable, and inexpensive. The reaction has shown to be general and high yielding.
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Affiliation(s)
- Silvia Gaspa
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Andrea Farina
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Mariella Tilocca
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Andrea Porcheddu
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, Cittadella Universitaria, 09042 Monserrato, Italy
| | - Luisa Pisano
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Massimo Carraro
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Ugo Azzena
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Lidia De Luca
- Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, 07100 Sassari, Italy
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Johansen MB, Gedde OR, Mayer TS, Skrydstrup T. Access to Aryl and Heteroaryl Trifluoromethyl Ketones from Aryl Bromides and Fluorosulfates with Stoichiometric CO. Org Lett 2020; 22:4068-4072. [PMID: 32391697 DOI: 10.1021/acs.orglett.0c01117] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We report a sequential one-pot preparation of aromatic trifluoromethyl ketones starting from readily accessible aryl bromides and fluorosulfates, the latter easily prepared from the corresponding phenols. The methodology utilizes low pressure carbon monoxide generated ex situ from COgen to generate Weinreb amides as reactive intermediates that undergo monotrifluoromethylation affording the corresponding aromatic trifluoromethyl ketones (TFMKs) in good yields. The stoichiometric use of CO enables the possibility for accessing 13C-isotopically labeled TFMK by switching to the use of 13COgen.
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Affiliation(s)
- Martin B Johansen
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.,Department of Engineering, Aarhus University, Åbogade 40, DK-8200 Aarhus N, Denmark
| | - Oliver R Gedde
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Thea S Mayer
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Troels Skrydstrup
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO), and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
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Buchspies J, Rahman MM, Szostak R, Szostak M. N-Acylcarbazoles and N-Acylindoles: Electronically Activated Amides for N–C(O) Cross-Coupling by Nlp to Ar Conjugation Switch. Org Lett 2020; 22:4703-4709. [DOI: 10.1021/acs.orglett.0c01488] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jonathan Buchspies
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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41
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Senatore R, Malik M, Spreitzer M, Holzer W, Pace V. Direct and Chemoselective Electrophilic Monofluoromethylation of Heteroatoms ( O-, S-, N-, P-, Se-) with Fluoroiodomethane. Org Lett 2020; 22:1345-1349. [PMID: 32004004 PMCID: PMC7205393 DOI: 10.1021/acs.orglett.9b04654] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The commercially available fluoroiodomethane represents a valuable and effective electrophilic source for transferring the CH2F unit to a series of heteroatom-centered nucleophiles under mild basic conditions. The excellent manipulability offered by its liquid physical state (bp 53.4 °C) enables practical and straightforward one-step nucleophilic substitutions to retain the chiral information embodied, thus allowing it to overcome de facto the requirement for fluoromethylating agents with no immediate access. The high-yielding methodology was successfully applied to a variety of nucleophiles including a series of drugs currently in the market.
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Affiliation(s)
- Raffaele Senatore
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse , 14-1090 Vienna , Austria
| | - Monika Malik
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse , 14-1090 Vienna , Austria
| | - Markus Spreitzer
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse , 14-1090 Vienna , Austria
| | - Wolfgang Holzer
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse , 14-1090 Vienna , Austria
| | - Vittorio Pace
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse , 14-1090 Vienna , Austria
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Kohlbacher SM, Ionasz VS, Ielo L, Pace V. The synthetic versatility of the Tiffeneau–Demjanov chemistry in homologation tactics. MONATSHEFTE FUR CHEMIE 2019. [DOI: 10.1007/s00706-019-02514-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Abstract
The Tiffeneau–Demjanov rearrangement can be regarded as an interesting alternative to the more common semi-pinacol transposition. It is usually employed for ring extension but, under specific conditions, it can also be used for ring contraction. Compared to other techniques, such as the Demjanov rearrangement or homologations with diazo compounds, the Tiffeneau–Demjanov pathway presents attractive features including high yielding and selective processes. Ring enlargements follow very strict and simple rules, such as the movement of the less substituted carbon and retention of the configuration. The rearrangement process is mainly affected by steric factors, due to presence of neighbouring groups, rather than electronic ones. The ring contraction may be achieved positioning the amine within the ring, thus achieving a high level of control. Unfortunately, applications of the reaction in modern homologation chemistry are rare; therefore, the aim of the review is re-proposing to the synthetic community the versatility of this venerable reaction and thus, spurring its employment for tackling challenging homologations processes.
Graphic abstract
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43
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Miele M, D'Orsi R, Sridharan V, Holzer W, Pace V. Highly chemoselective difluoromethylative homologation of iso(thio)cyanates: expeditious access to unprecedented α,α-difluoro(thio)amides. Chem Commun (Camb) 2019; 55:12960-12963. [PMID: 31602439 DOI: 10.1039/c9cc06929a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The new motif - α,α-difluoromethyl thioamide - has been assembled starting from isothiocyanate (as thioamide precursor) and a formal difluoromethyl-carbanion generated from commercially available TMSCHF2. Upon proper activation of this reagent with potassium tert-amylate, the high-yielding transfer of the difluorinated nucleophile takes place under high chemocontrol. Various sensitive functionalities (e.g. ester, nitrile, nitro, azido groups) can be accommodated across the isothiocyanate core, thus allowing a wide scope. The methodology is highly flexible and adaptable to prepare analogous α,α-difluoromethyl oxoamides by conveniently using isocyanates as the electrophilic building-blocks.
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Affiliation(s)
- Margherita Miele
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
| | - Rosarita D'Orsi
- Department of Sciences, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Vellaisamy Sridharan
- Department of Chemistry and Chemical Sciences, Central University of Jammu, Rahya-Suchani (Bagla), 181143, India
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
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