1
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Zorba L, Stylianakis I, Tsoureas N, Kolocouris A, Vougioukalakis GC. Copper-Catalyzed One-Pot Synthesis of Thiazolidin-2-imines. J Org Chem 2024; 89:7727-7740. [PMID: 38725347 PMCID: PMC11190980 DOI: 10.1021/acs.joc.4c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 03/27/2024] [Accepted: 04/30/2024] [Indexed: 06/23/2024]
Abstract
The synthesis of thiazolines, thiazolidines, and thiazolidinones has been extensively studied, due to their biological activity related to neurodegenerative diseases, such as Parkinson's and Alzheimer's, as well as their antiparasitic and antihypertensive properties. The closely related thiazolidin-2-imines have been studied less, and efficient strategies for synthesizing them, mainly based on the reaction of propargylamines with isothiocyanates, have been explored less. The use of one-pot approaches, providing modular, straightforward, and sustainable access to these compounds, has also received very little attention. Herein, we report a novel, one-pot, multicomponent, copper-catalyzed reaction among primary amines, ketones, terminal alkynes, and isothiocyanates, toward thiazolidin-2-imines bearing quaternary carbon centers on the five-membered ring, in good to excellent yields. Density functional theory calculations, combined with experimental mechanistic findings, suggest that the copper(I)-catalyzed reaction between the in situ-formed propargylamines and isothiocyanates proceeds with a lower energy barrier in the pathway leading to the S-cyclized product, compared to that of the N-cyclized one, toward the chemo- and regioselective formation of 5-exo-dig S-cyclized thiazolidin-2-imines.
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Affiliation(s)
- Leandros
P. Zorba
- Laboratory
of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimioupolis, 15771 Athens, Greece
| | - Ioannis Stylianakis
- Laboratory
of Medicinal Chemistry, Section of Pharmaceutical Chemistry, Department
of Pharmacy, National and Kapodistrian University
of Athens, Panepistimioupolis
Zografou, 15771 Athens, Greece
| | - Nikolaos Tsoureas
- Laboratory
of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimioupolis, 15771 Athens, Greece
| | - Antonios Kolocouris
- Laboratory
of Medicinal Chemistry, Section of Pharmaceutical Chemistry, Department
of Pharmacy, National and Kapodistrian University
of Athens, Panepistimioupolis
Zografou, 15771 Athens, Greece
| | - Georgios C. Vougioukalakis
- Laboratory
of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimioupolis, 15771 Athens, Greece
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2
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Das B, Dahiya A, Patel BK. Isothiocyanates: happy-go-lucky reagents in organic synthesis. Org Biomol Chem 2024; 22:3772-3798. [PMID: 38656266 DOI: 10.1039/d4ob00281d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Owing to their unique structural features, isothiocyanates (ITCs) are a class of highly useful and inimitable reagents as the -NCS group serves both as electrophile and nucleophile in organic synthesis. ITCs share a rich legacy in organic, medicinal, and combinatorial chemistry. Compared to their oxygen equivalents, isocyanates, ITCs are easily available, less unpleasant, and somewhat less harmful to work with (mild conditions) which makes them happy-go-lucky reagents. Functionalized ITCs can finely tune the reactivity of the -NCS group and thus can be exploited in the late-stage functionalization processes. This review's primary aim is to outline ITC chemistry in the construction and derivatization of heterocycles through the lens of sustainability. For ease and brevity, the sections are divided based on reactive centers present in functionalized ITCs and modes of cyclisation. Scrutinizing their probable unexplored directions for future research studies is also addressed.
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Affiliation(s)
- Bubul Das
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India.
- Department of Chemistry, Bagadhar Brahma Kishan College, Jalah, Assam 781327, India
| | - Anjali Dahiya
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India.
| | - Bhisma K Patel
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India.
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3
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Salvador-Gil D, Herrera RP, Gimeno MC. Catalysis-free synthesis of thiazolidine-thiourea ligands for metal coordination (Au and Ag) and preliminary cytotoxic studies. Dalton Trans 2023. [PMID: 36880202 DOI: 10.1039/d3dt00079f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
The reaction of propargylamines with isothiocyanates results in the selective formation of iminothiazolidines, aminothiazolines or mixed thiazolidine-thiourea compounds under mild conditions. It has been observed that secondary propargylamines lead to the selective formation of cyclic 2-amino-2-thiazoline derivatives, while primary propargylamines form iminothiazoline species. In addition, these cyclic thiazoline derivatives can further react with an excess of isothiocyanate to give rise to thiazolidine-thiourea compounds. These species can also be achieved by reaction of propargylamines with isothiocynates in a molar ratio of 1 : 2. Coordination studies of these heterocyclic species towards silver and gold with different stoichiometries have been carried out and complexes of the type [ML(PPh3)]OTf, [ML2]OTf (M = Ag, Au) or [Au(C6F5)L] have been synthesised. Preliminary studies of the cytotoxic activity in lung cancer cells have also been performed in both ligands and complexes, showing that although the ligands do not exhibit anticancer activity, their coordination to metals, especially silver, greatly enhances the cytotoxic activity.
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Affiliation(s)
- Daniel Salvador-Gil
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
| | - Raquel P Herrera
- Departamento de Química Orgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - M Concepción Gimeno
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
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4
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Aziz MN, Nguyen L, Chang Y, Gout D, Pan Z, Lovely CJ. Novel thiazolidines of potential anti-proliferation properties against esophageal squamous cell carcinoma via ERK pathway. Eur J Med Chem 2023; 246:114909. [PMID: 36508971 DOI: 10.1016/j.ejmech.2022.114909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 11/25/2022]
Abstract
The discovery of a new class of extracellular-signal-regulated kinase (ERK) inhibitors has been achieved via developing novel 2-imino-5-arylidene-thiazolidine analogues. A novel synthetic method employing a solid support-mediated reaction was used to construct the targeted thiazolidines through a cascade reaction with good yields. The chemical and physical stability of the new thiazolidine library has successfully been achieved by blocking the labile C5-position to aerobic oxidation. A cell viability study was performed using esophageal squamous cell carcinoma cell lines (KYSE-30 and KYSE-150) and non-tumorous esophageal epithelial cell lines (HET-1A and NES-G4T) through utilization of an MTT assay, revealing that (Z)-5-((Z)-4-bromobenzylidene)-N-(4-methoxy-2-nitrophenyl)-4,4-dimethylthiazolidin-2-imine (6g) was the best compound among the synthesized library in terms of selectivity. DAPI staining experiments were performed to visualize the morphological changes and to investigate the apoptotic activity. Moreover, western blots were used to probe the mechanism/pathway behind the observed activity/selectivity of thiazolidine 6g which established selective inhibition of phosphorylation in the ERK pathway. Molecular modeling techniques have been utilized to confirm the observed activity. A molecular docking study revealed similar binding interactions between the synthesized thiazolidines and reported co-crystalized inhibitors with ERK proteins. Thus, the present study provides a starting point for the development of interesting bioactive 2-imino-5-arylidene-thiazolidines.
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Affiliation(s)
- Marian N Aziz
- Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, TX, 76019, USA; Department of Pesticide Chemistry, National Research Centre, Dokki, Giza, 12622, Egypt
| | - Linh Nguyen
- Dept. of Biology, College of Science, University of Texas at Arlington, TX, 76019, USA; Department of Graduate Nursing, College of Nursing and Health Innovation, University of Texas at Arlington, TX, 76019, USA
| | - Yan Chang
- Department of Graduate Nursing, College of Nursing and Health Innovation, University of Texas at Arlington, TX, 76019, USA; Bone and Muscle Research Center, University of Texas at Arlington, TX, 76019, USA
| | - Delphine Gout
- Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, TX, 76019, USA
| | - Zui Pan
- Department of Graduate Nursing, College of Nursing and Health Innovation, University of Texas at Arlington, TX, 76019, USA; Bone and Muscle Research Center, University of Texas at Arlington, TX, 76019, USA
| | - Carl J Lovely
- Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, TX, 76019, USA.
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5
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Aziz MN, Patel A, Iskander A, Chini A, Gout D, Mandal SS, Lovely CJ. One-Pot Synthesis of Novel 2-Imino-5-Arylidine-Thiazolidine Analogues and Evaluation of Their Anti-Proliferative Activity against MCF7 Breast Cancer Cell Line. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27030841. [PMID: 35164106 PMCID: PMC8840064 DOI: 10.3390/molecules27030841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/14/2022] [Accepted: 01/21/2022] [Indexed: 11/20/2022]
Abstract
An efficient surface-mediated synthetic method to facilitate access to a novel class of thiazolidines is described. The rationale behind the design of the targeted thiazolidines was to prepare stable thiazolidine analogues and evaluate their anti-proliferative activity against a breast cancer cell line (MCF7). Most of the synthesized analogues exhibited increased potency ranging from 2–15-fold higher compared to the standard reference, cisplatin. The most active thiazolidines contain a halogenated or electron withdrawing group attached to the N-phenyl ring of exocyclic 2-imino group. However, combination of the two substituents did not enhance the activity. The anti-proliferative activity was measured in terms of IC50 values using an MTT assay.
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Affiliation(s)
- Marian N. Aziz
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
- Department of Pesticide Chemistry, National Research Centre, Dokki, Giza 12622, Egypt
| | - Arzoo Patel
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
| | - Amany Iskander
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
| | - Avisankar Chini
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
| | - Delphine Gout
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
| | - Subhrangsu S. Mandal
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
| | - Carl J. Lovely
- Department of Chemistry and Biochemistry, University of Texas-Arlington, Arlington, TX 76019-0065, USA; (M.N.A.); (A.P.); (A.I.); (A.C.); (D.G.); (S.S.M.)
- Correspondence:
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6
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Xiang L, Wu H, Liang Y, Deng H, He Y, Xu Q, Zhang J. Ag(I)-Catalyzed rapid access to 2-amino-4-methylenethiazolines with potential applications in bioconjugation chemistry. Org Biomol Chem 2021; 19:4060-4066. [PMID: 33978054 DOI: 10.1039/d1ob00464f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An Ag(i)-catalyzed tandem addition-cyclization of isothiocyanate and propargylamine was successfully applied to the synthesis of 2-amino-4-methylenethiazolines. This route features an unprecedented fast reaction rate with full conversion reached within 10 min at room temperature for aromatic isothiocyanates and excellent chemoselectivity for exocyclic products. The application of this strategy is further highlighted by the accelerated bioconjugation of propargylamine with fluorescein isothiocyanate (FITC) under Ag(i)-catalysis.
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Affiliation(s)
- Lingling Xiang
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Haiting Wu
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Yunshi Liang
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Huiying Deng
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Yiting He
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Qin Xu
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
| | - Jing Zhang
- Artemisinin Research Center and The First Affiliated Hospital, Guangzhou University of Chinese Medicine, 12 Jichang Road, Guangzhou 510405, China.
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7
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Aziz MN, Singh RP, Gout D, Lovely CJ. Dearomatizing spirocyclization of thioureas, ureas and guanidines. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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8
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Enantiomeric Separation of New Chiral Azole Compounds. Molecules 2021; 26:molecules26010213. [PMID: 33406592 PMCID: PMC7796373 DOI: 10.3390/molecules26010213] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 12/30/2020] [Accepted: 01/01/2021] [Indexed: 11/16/2022] Open
Abstract
Twelve new azole compounds were synthesized through an ene reaction involving methylidene heterocycles and phenylmaleimide, producing four oxazoles, five thiazoles, and one pyridine derivative, and ethyl glyoxylate for an oxazole and a thiazole compound. The twelve azoles have a stereogenic center in their structure. Hence, a method to separate the enantiomeric pairs, must be provided if any further study of chemical and pharmacological importance of these compounds is to be accomplished. Six chiral stationary phases were assayed: four were based on macrocyclic glycopeptide selectors and two on linear carbohydrates, i.e., derivatized maltodextrin and amylose. The enantiomers of the entire set of new chiral azole compounds were separated using three different mobile phase elution modes: normal phase, polar organic, and reversed phase. The most effective chiral stationary phase was the MaltoShell column, which was able to separate ten of the twelve compounds in one elution mode or another. Structural similarities in the newly synthesized oxazoles provided some insights into possible chiral recognition mechanisms.
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Wang H, Wu X, Wang L, Li E, Li X, Tong T, Kang H, Xie J, Shen G, Lv X. One-Pot Synthesis of Benzimidazo[2,1- b]thiazoline Derivatives through an Addition/Cyclization/Oxidative Coupling Reaction. J Org Chem 2020; 85:11934-11941. [PMID: 32815368 DOI: 10.1021/acs.joc.0c01137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel and efficient approach to the synthesis of benzimidazo[2,1-b]thiazoline derivatives has been developed through an addition/cyclization/intramolecular oxidative C-H functionalization process. A variety of alkylene benzimidazo[2,1-b] thiazolines were conveniently assembled from the reaction of aryl isothiocyanate and propargylic amine in the presence of Cu(OAc)2 and PIFA at room temperature. The product could be further converted to substituted benzimidazo[2,1-b]thiazole derivatives.
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Affiliation(s)
- Haofeng Wang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Xin Wu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Luyu Wang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Erfei Li
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Xiaoyu Li
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Tao Tong
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Honglan Kang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Jianwu Xie
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Guodong Shen
- School of Chemistry and Chemical Engineering, Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, Liaocheng University, Liaocheng 252059, Shandong, People's Republic of China
| | - Xin Lv
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China
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Morris LL, Alvarado CA, Goncalves JM, Singh RP, Lovely CJ, Yousufuddin M. [4-(4-Methoxyphenyl)-8-oxo-3-(phenylselanyl)spiro[4.5]deca-3,6,9-trien-2-yl]methylcyanamide. IUCRDATA 2020; 5:x200078. [DOI: 10.1107/s2414314620000784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 01/22/2020] [Indexed: 11/11/2022] Open
Abstract
The title compound, C25H22N2O2Se, crystallizes in the space group P21/c with one molecule in the asymmetric unit. The compound was synthesized by the addition of phenylselenyl bromide to a cyanamide. The phenylselenyl portion and the cyano group, as well as the ketone functional group in the cyclohexa-2,5-dien-1-one portion of the structure, are disordered, with occupancy factors of 0.555 (14) and 0.445 (14).
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Mao ZY, Liu YW, Ma RJ, Ye JL, Si CM, Wei BG, Lin GQ. Divergent synthesis of N-heterocyclic 1,6-enynes through a zinc-catalyzed decarboxylative A 3 reaction. Chem Commun (Camb) 2019; 55:14170-14173. [PMID: 31701971 DOI: 10.1039/c9cc06985b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A zinc-catalyzed decarboxylative A3 reaction of cyclic amino acids, α,β-unsaturated aldehydes and terminal alkynes has been developed. A series of functionalized N-heterocyclic 1,6-enynes have been successfully obtained with excellent regioselectivities through this novel approach. In addition, the utility of this straightforward process is demonstrated by the preparation of a polycyclic nitrogen-containing heterocyclic compound.
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Affiliation(s)
- Zhuo-Ya Mao
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, China.
| | - Yi-Wen Liu
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, China.
| | - Rui-Jun Ma
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, China.
| | - Jian-Liang Ye
- College of Chemistry and Chemical Engineering and the Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen 361005, China
| | - Chang-Mei Si
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, China.
| | - Bang-Guo Wei
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, China.
| | - Guo-Qiang Lin
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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12
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Development of a Telescoped Flow Process for the Safe and Effective Generation of Propargylic Amines. MOLECULES (BASEL, SWITZERLAND) 2019; 24:molecules24203658. [PMID: 31658759 PMCID: PMC6833020 DOI: 10.3390/molecules24203658] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 10/07/2019] [Accepted: 10/08/2019] [Indexed: 12/28/2022]
Abstract
Propargylic amines are important multifunctional building blocks that are frequently exploited in the synthesis of privileged heterocyclic entities. Herein we report on a novel flow process that achieves the safe and effective on-demand synthesis of propargylic amines in a telescoped manner. This process minimizes exposure to hazardous azide intermediates and renders a streamlined route into these building blocks. The value of this approach is demonstrated by the rapid generation of a small selection of drug-like thiazolines that result from a high-yielding reaction cascade between propargylic amines with different aryl isothiocyanates.
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