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Liu X, Yang D, Liu Z, Wang Y, Liu Y, Wang S, Wang P, Cong H, Chen YH, Lu L, Qi X, Yi H, Lei A. Unraveling the Structure and Reactivity Patterns of the Indole Radical Cation in Regioselective Electrochemical Oxidative Annulations. J Am Chem Soc 2023; 145:3175-3186. [PMID: 36705997 DOI: 10.1021/jacs.2c12902] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Oxidation-induced strategy for inert chemical bond activation through highly active radical cation intermediate has exhibited unique reactivity. Understanding the structure and reactivity patterns of radical cation intermediates is crucial in the mechanistic study and will be beneficial for developing new reactions. In this work, the structure and properties of indole radical cations have been revealed using time-resolved transient absorption spectroscopy, in situ electrochemical UV-vis, and in situ electrochemical electron paramagnetic resonance (EPR) technique. Density functional theory (DFT) calculations were used to explain and predict the regioselectivity of several electrochemical oxidative indole annulations. Based on the understanding of the inherent properties of several indole radical cations, two different regioselective annulations of indoles have been successfully developed under electrochemical oxidation conditions. Varieties of furo[2,3-b]indolines and furo[3,2-b]indolines were synthesized in good yields with high regioselectivities. Our mechanistic insights into indole radical cations will promote the further development of oxidation-induced indole functionalizations.
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Affiliation(s)
- Xing Liu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Dali Yang
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Zhao Liu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Yunkun Wang
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Yichang Liu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Shengchun Wang
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Pengjie Wang
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Hengjiang Cong
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Yi-Hung Chen
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Lijun Lu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Xiaotian Qi
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Hong Yi
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China
| | - Aiwen Lei
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P. R. China.,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, P. R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
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2
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Hong MJ, Hao MJ, Zhang GY, Li HJ, Shao ZZ, Liu XP, Ma WZ, Xu J, Mahmud T, Lan WJ. Exophilone, a Tetrahydrocarbazol-1-one Analogue with Anti-Pulmonary Fibrosis Activity from the Deep-Sea Fungus Exophiala oligosperma MCCC 3A01264. Mar Drugs 2022; 20:md20070448. [PMID: 35877741 PMCID: PMC9317524 DOI: 10.3390/md20070448] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/03/2022] [Accepted: 07/04/2022] [Indexed: 12/10/2022] Open
Abstract
A new compound, exophilone (1), together with nine known compounds (2–10), were isolated from a deep-sea-derived fungus, Exophiala oligosperma. Their chemical structures, including the absolute configuration of 1, were elucidated using nuclear magnetic resonance (NMR) spectroscopy, high-resolution electrospray ionization mass spectroscopy (HRESIMS), and electronic circular dichroism (ECD) calculation. Compounds were preliminarily screened for their ability to inhibit collagen accumulation. Compounds 1, 4, and 7 showed weaker inhibition of TGF-β1-induced total collagen accumulation in compared with pirfenidone (73.14% inhibition rate). However, pirfenidone exhibited cytotoxicity (77.57% survival rate), while compounds 1, 4, and 7 showed low cytotoxicity against the HFL1 cell line. Particularly, exophilone (1) showed moderate collagen deposition inhibition effect (60.44% inhibition rate) and low toxicity in HFL1 cells (98.14% survival rate) at a concentration of 10 μM. A molecular docking study suggests that exophilone (1) binds to both TGF-β1 and its receptor through hydrogen bonding interactions. Thus, exophilone (1) was identified as a promising anti-pulmonary fibrosis agent. It has the potential to be developed as a drug candidate for pulmonary fibrosis.
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Affiliation(s)
- Ming-Jun Hong
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; (M.-J.H.); (M.-J.H.); (G.-Y.Z.); (J.X.)
| | - Meng-Jiao Hao
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; (M.-J.H.); (M.-J.H.); (G.-Y.Z.); (J.X.)
| | - Guang-Yu Zhang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; (M.-J.H.); (M.-J.H.); (G.-Y.Z.); (J.X.)
| | - Hou-Jin Li
- School of Chemistry, Sun Yat-sen University, Guangzhou 510006, China;
| | - Zong-Ze Shao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China; (Z.-Z.S.); (X.-P.L.)
| | - Xiu-Pian Liu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China; (Z.-Z.S.); (X.-P.L.)
| | - Wen-Zhe Ma
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa 519020, Macau, China;
| | - Jun Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; (M.-J.H.); (M.-J.H.); (G.-Y.Z.); (J.X.)
| | - Taifo Mahmud
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331, USA;
| | - Wen-Jian Lan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; (M.-J.H.); (M.-J.H.); (G.-Y.Z.); (J.X.)
- Correspondence: ; Tel.: +86-20-399-43-042
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Identification of 5-Methoxy-2-(Diformylmethylidene)-3,3-Dimethylindole as an Anti-Influenza A Virus Agent. PLoS One 2017; 12:e0170352. [PMID: 28114392 PMCID: PMC5256998 DOI: 10.1371/journal.pone.0170352] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 01/03/2017] [Indexed: 12/25/2022] Open
Abstract
Influenza virus is estimated to cause 3–5 million severe complications and about 250–500 thousand deaths per year. Different kinds of anti-influenza virus drugs have been developed. However, the emergence of drug resistant strains has presented a big challenge for efficient antiviral therapy. Indole derivatives have been shown to exhibit both antiviral and anti-inflammatory activities. In this study, we adopted a cell-based system to screen for potential anti-IAV agents. Four indole derivatives (named 525A, 526A, 527A and 528A) were subjected to the antiviral screening, of which 526A was selected for further investigation. We reported that pre-treating cells with 526A protects cells from IAV infection. Furthermore, 526A inhibits IAV replication by inhibiting the expression of IAV genes. Interestingly, 526A suppresses the activation of IRF3 and STAT1 in host cells and thus represses the production of type I interferon response and cytokines in IAV-infected cells. Importantly, 526A also partially blocks the activation of RIG-I pathway. Taken together, these results suggest that 526A may be a potential anti-influenza A virus agent.
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Karwehl S, Jansen R, Huch V, Stadler M. Sorazolons, Carbazole Alkaloids from Sorangium cellulosum Strain Soce375. JOURNAL OF NATURAL PRODUCTS 2016; 79:369-375. [PMID: 26866461 DOI: 10.1021/acs.jnatprod.5b00997] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Sorazolons A (1) to E2 (9) were isolated from Sorangium cellulosum strain Soce375. Their molecular structures were elucidated using extensive HRESIMS and NMR analysis. The absolute configuration of sorazolon A (1) was determined by comparison of the experimental CD spectrum with quantum chemical calculated spectra for both enantiomers. Sorazolons D2 (7), E (8), and E2 (9) exhibit a moderate cytotoxic activity against mouse fibroblast cell line L929 with IC50 values between 5.0 μM and 0.09 mM.
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Affiliation(s)
- Sabrina Karwehl
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
| | - Rolf Jansen
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
| | - Volker Huch
- Department of Inorganic Chemistry, Saarland University , Building C 4.1, 66123 Saarbrücken, Germany
| | - Marc Stadler
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
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Ximenes VF, Lopes MG, Petrônio MS, Regasini LO, Silva DHS, da Fonseca LM. Inhibitory effect of gallic acid and its esters on 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione in erythrocytes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:5355-5362. [PMID: 20397726 DOI: 10.1021/jf100233y] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The protective effect of gallic acid and its esters, methyl, propyl, and lauryl gallate, against 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione (GSH) in erythrocytes was studied. The inhibition of hemolysis was dose-dependent, and the esters were significantly more effective than gallic acid. Gallic acid and its esters were compared with regard to their reactivity to free radicals, using the DPPH and AAPH/pyranine free-cell assays, and no significant difference was obtained. Gallic acid and its esters not only failed to inhibit the depletion of intracellular GSH in erythrocytes induced by AAPH but exacerbated it. Similarly, the oxidation of GSH by AAPH or horseradish peroxidase/H(2)O(2) in cell-free systems was exacerbated by gallic acid or gallates. This property could be involved in the recent findings on pro-apoptotic and pro-oxidant activities of gallates in tumor cells. We provide evidence that lipophilicity and not only radical scavenger potency is an important factor regarding the efficiency of antihemolytic substances.
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Affiliation(s)
- Valdecir F Ximenes
- Departamento de Química, Faculdade de Ciências, Unesp-University Estadual Paulista, Bauru, São Paulo (SP), Brazil.
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Shirinzadeh H, Eren B, Gurer-Orhan H, Suzen S, Özden S. Novel indole-based analogs of melatonin: synthesis and in vitro antioxidant activity studies. Molecules 2010; 15:2187-202. [PMID: 20428037 PMCID: PMC6257329 DOI: 10.3390/molecules15042187] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/15/2010] [Accepted: 03/23/2010] [Indexed: 01/16/2023] Open
Abstract
The aim of this study was to synthesize and examine possible in vitro antioxidant effects of indole-based melatonin analogue compounds. As a part of our ongoing study nineteen indole hydrazide/hydrazone derivatives were synthesized, characterized and their in vitro antioxidant activity was investigated by three different assays: by evaluating their reducing effect against oxidation of a redox sensitive fluorescent probe, by examining their protective effect against H2O2-induced membrane lipid peroxidation and by determining their inhibitory effect on AAPH–induced hemolysis of human erythrocytes. The results indicated significant strong antioxidant activity for most of the compounds, when compared to melatonin.
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Affiliation(s)
- Hanif Shirinzadeh
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ankara University, 06100 Tandogan, Ankara, Turkey
| | - Burcu Eren
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ege University, 35100 Bornova, Izmir, Turkey
| | - Hande Gurer-Orhan
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ege University, 35100 Bornova, Izmir, Turkey
| | - Sibel Suzen
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ankara University, 06100 Tandogan, Ankara, Turkey
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +90 312 2033074; Fax: +90 312 2131081
| | - Seçkin Özden
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ankara University, 06100 Tandogan, Ankara, Turkey
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