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Merten C. Modelling solute-solvent interactions in VCD spectra analysis with the micro-solvation approach. Phys Chem Chem Phys 2023; 25:29404-29414. [PMID: 37881890 DOI: 10.1039/d3cp03408a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Vibrational circular dichroism (VCD) spectroscopy has become an important part of the (stereo-)chemists' toolbox as a reliable method for the determination of absolute configurations. Being the chiroptical version of infrared spectroscopy, it has also been recognized as being very sensitive to conformational changes and intermolecular interactions. This sensitivity originates from the fact that the VCD spectra of individual conformers are often more different than their IR spectra, so that changes in conformational distributions or band positions and intensities become more pronounced. What is an advantage for studies focussing on intermolecular interactions can, however, quickly turn into a major obstacle during AC determinations: solute-solvent interactions can have a strong influence on spectral signatures and they must be accurately treated when simulating VCD and IR spectra. In this perspective, we showcase selected examples which exhibit particularly pronounced solvent effects. It is demonstrated that it is typically sufficient to model solute-solvent interactions by placing single solvent molecules near hydrogen bonding sites of the solute and subsequently use the optimized structures for spectra simulations. This micro-solvation approach works reasonably well for medium-sized, not too conformationally flexible molecules. We thus also discuss its limitations and outline the next steps that method development needs to take in order to further improve the workflows for VCD spectra predictions.
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Affiliation(s)
- Christian Merten
- Ruhr Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany.
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Bitchagno GTM, Nchiozem-Ngnitedem VA, Melchert D, Fobofou SA. Demystifying racemic natural products in the homochiral world. Nat Rev Chem 2022; 6:806-822. [PMID: 37118098 PMCID: PMC9562063 DOI: 10.1038/s41570-022-00431-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2022] [Indexed: 12/03/2022]
Abstract
Natural products possess structural complexity, diversity and chirality with attractive functions and biological activities that have significantly impacted drug discovery initiatives. Chiral natural products are abundant in nature but rarely occur as racemates. The occurrence of natural products as racemates is very intriguing from a biosynthetic point of view; as enzymes are chiral molecules, enzymatic reactions generating natural products should be stereospecific and lead to single-enantiomer products. Despite several reports in the literature describing racemic mixtures of stereoisomers isolated from natural sources, there has not been a comprehensive review of these intriguing racemic natural products. The discovery of many more natural racemates and their potential enzymatic sources in recent years allows us to describe the distribution and chemical diversity of this ‘class of natural products’ to enrich discussions on biosynthesis. In this Review, we describe the chemical classes, occurrence and distribution of pairs of enantiomers in nature and provide insights about recent advances in analytical methods used for their characterization. Special emphasis is on the biosynthesis, including plausible enzymatic and non-enzymatic formation of natural racemates, and their pharmacological significance. ![]()
Racemic natural products display a wealth of bioactivities and chemical diversity. Their derivation from intriguing racemization processes, through enzymatic or non-enzymatic pathways, are discussed here, as well as their pharmacological properties and the analytical techniques developed for their identification, resolution and characterization.
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Rani D, Gulati V, Guleria M, Singh SP, Agarwal J. Aqueous synthesis of 2-aryl-3-nitro-2H chromenes via l-prolinamide mediated tandem oxa-Michael Henry reactions. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Grassin C, Santoro E, Merten C. 7-Azaindole breaks carboxylic acid dimers and simplifies VCD spectra analyses of natural products. Chem Commun (Camb) 2022; 58:11527-11530. [PMID: 36149377 DOI: 10.1039/d2cc04433a] [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 determination of absolute configurations of carboxylic acids by vibrational circular dichroism (VCD) spectroscopy is often complicated by self-aggregation and the subsequent need to compute the spectra of the aggregates. We show that 7-azaindole effectively breaks up these aggregates by stronger complemental hydrogen bonding to the COOH moiety, enabling drastic simplification and acceleration of VCD spectra calculations.
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Affiliation(s)
- Corentin Grassin
- Ruhr-Universität Bochum, Organische Chemie 2, Stereochemistry and Chiroptical Spectroscopy, Universitätsstraße 150, 44801, Bochum, Germany.
| | - Ernesto Santoro
- Ruhr-Universität Bochum, Organische Chemie 2, Stereochemistry and Chiroptical Spectroscopy, Universitätsstraße 150, 44801, Bochum, Germany.
| | - Christian Merten
- Ruhr-Universität Bochum, Organische Chemie 2, Stereochemistry and Chiroptical Spectroscopy, Universitätsstraße 150, 44801, Bochum, Germany.
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Silva DHS, Mannochio-Russo H, Lago JHG, Bueno PCP, Medina RP, Bolzani VDS, Vilegas W, Nunes WDG. Bioprospecting as a strategy for conservation and sustainable use of the Brazilian Flora. BIOTA NEOTROPICA 2022. [DOI: 10.1590/1676-0611-bn-2022-1356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Abstract In Brazil, research with natural products had a strong impulse when FAPESP supported the creation of the Laboratory of Chemistry of Natural Products of the Institute of Chemistry of USP (1966). In 1999, FAPESP launched the Research Program in the Characterization, Conservation, Restoration and Sustainable Use of Biodiversity (BIOTA-FAPESP), which intensified the sustainable exploitation of biodiversity, and which evolved to form the Biota Network for Bioprospection and Bioassays (BIOprospecTA), which integrates groups from all over the country, optimizing the use of the skills already installed for the bioprospecting of microorganisms, plants, invertebrates, vertebrates and marine organisms. Of the 104 projects related to plant sciences, 35 carried out bioprospection of Brazilian flora, belonging to the areas of Chemistry, Botany, Genetics, Plant Physiology, Plant Morphology, Plant (Chemo)taxonomy, Ecosystem Ecology, Plant Genetics. Physical Sciences, Forest Resources, Forestry Engineering, Agronomy, leading to thousands of publications, engagement of hundreds of students and a deeper understanding of natural products in different biological models through macromolecules analysis aided by computational and spectrometric strategies, in addition to pharmacological evaluations. The development of omics approaches led to a more comprehensive view of the chemical profile of an organism, and enabled integrated and concomitant studies of several samples, and faster annotation of known molecules, through the use of hyphenated and chemometric techniques, and molecular networking. This also helped to overcome the lack of information on the safety and efficacy of herbal preparations, in projects dealing with the standardization of herbal products, according to international standards. The BIOTA-FAPESP program has also focused on environmental aspects, in accordance with the principles of Green Chemistry and has had positive effects on international collaboration, on the number and impact of scientific publications and on partnership with companies, a crucial step to add value and expand the production chain of bioproducts. Also, the compilation, systematization and sharing of data were contemplated with the creation of the NUBBEDB database, of free access, and that integrates with international databases (ACD/labs, American Chemical Society – ACS), helping researchers and companies in the development from different areas of science, technology, strengthening the bioeconomy and subsidizing public policies.
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Ramos YJ, da Costa-Oliveira C, Candido-Fonseca I, de Queiroz GA, Guimarães EF, Defaveri ACAE, Sadgrove NJ, Moreira DDL. Advanced Chemophenetic Analysis of Essential Oil from Leaves of Piper gaudichaudianum Kunth (Piperaceae) Using a New Reduction-Oxidation Index to Explore Seasonal and Circadian Rhythms. PLANTS 2021; 10:plants10102116. [PMID: 34685925 PMCID: PMC8540104 DOI: 10.3390/plants10102116] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 11/16/2022]
Abstract
The aromatic species Piper gaudichaudianum Kunth (Piperaceae) is widely used in Brazil for medicinal and ritualistic applications. In the current study, chemophenetic patterns were realized across season and circadian rhythm based on the chemical profile of essential oils (EOs) from leaves. Hydrodistilled essential oils were analyzed by GC-MS and GC-FID, and a new calculation of metabolite oxidation level, averaged for each individual molecule component of the EO, was used to explore the patterns of metabolism/biosynthesis. This new index used an intermediate calculation, the 'weighted average redox standard' (SRO), to enable a value for mixtures of metabolites to be generated, the 'general mixture redox index' (GMOR). The indices were subjected to a proof-of-concept approach by making comparison to outcomes from multivariate analyses, i.e., PCA and HCA. Chemical analysis demonstrated that the essential oils were dominated by sesquiterpenes, constructed of 15 classes of compound (C-skeletons), and 4 C-skeletons were recognized in the monoterpene group, giving a total of 19. The variation of chemical profiles was distinct at different phenological stages, but stronger chemical variation was evident between day and night as compared to season. Furthermore, due to comprehensive sampling across different regions, nine chemotypes were recognized, including those previously reported. The SRO and GMRO indices demonstrate that phenological variation of chemistry is mainly an outcome of redox fluctuations in terpene biosynthesis, changing from day to night. These indices also corroborate that chemical diversity is increased with oxidative metabolism. Lastly, the current study demonstrates pronounced phenotypic plasticity in P. gaudichaudianum, which makes it a suitable candidate to help further our understanding of chemophenetics and chemical ecology.
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Affiliation(s)
- Ygor Jessé Ramos
- Instituto de Biologia, Pós-Graduação em Biologia Vegetal, Universidade do Estado do Rio de Janeiro, Maracanã, Rio de Janeiro 20550-013, Brazil;
- Diretoria de Pesquisa do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil;
- Centro de Responsabilidade Socioambiental do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil; (G.A.d.Q.); (A.C.A.e.D.)
- Fundação Oswaldo Cruz, Farmanguinhos, Manguinhos, Rio de Janeiro 21041-250, Brazil; (C.d.C.-O.); (I.C.-F.)
| | - Claudete da Costa-Oliveira
- Fundação Oswaldo Cruz, Farmanguinhos, Manguinhos, Rio de Janeiro 21041-250, Brazil; (C.d.C.-O.); (I.C.-F.)
| | - Irene Candido-Fonseca
- Fundação Oswaldo Cruz, Farmanguinhos, Manguinhos, Rio de Janeiro 21041-250, Brazil; (C.d.C.-O.); (I.C.-F.)
| | - George Azevedo de Queiroz
- Centro de Responsabilidade Socioambiental do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil; (G.A.d.Q.); (A.C.A.e.D.)
| | - Elsie Franklin Guimarães
- Diretoria de Pesquisa do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil;
| | - Anna C. Antunes e Defaveri
- Centro de Responsabilidade Socioambiental do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil; (G.A.d.Q.); (A.C.A.e.D.)
| | | | - Davyson de Lima Moreira
- Instituto de Biologia, Pós-Graduação em Biologia Vegetal, Universidade do Estado do Rio de Janeiro, Maracanã, Rio de Janeiro 20550-013, Brazil;
- Diretoria de Pesquisa do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Jardim Botânico, Rio de Janeiro 22460-030, Brazil;
- Fundação Oswaldo Cruz, Farmanguinhos, Manguinhos, Rio de Janeiro 21041-250, Brazil; (C.d.C.-O.); (I.C.-F.)
- Correspondence:
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Pouny I, Long C, Batut M, Aussagues Y, Jean Valère N, Achoundong G, David B, Lavaud C, Massiot G. Quinolizidine Alkaloids from Cylicomorpha solmsii. JOURNAL OF NATURAL PRODUCTS 2021; 84:1198-1202. [PMID: 33606529 DOI: 10.1021/acs.jnatprod.0c01261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Five new quinolizidine alkaloids were isolated from the leaves of Cylicomorpha solmstii (Urb.) Urb. (Caricaceae) and named cylicomorphins A-E (1-5). They all are ester derivatives of the same basic quinolizidine skeleton bearing hydroxy, methyl, and ethanoic acid substituents. Their structures were mainly established by NMR spectroscopy, and the absolute configuration is proposed on the basis of VCD data and Mosher ester derivatization. Compound 5 displayed cytotoxicity in the 10 μM range against an HCT-116 cell line.
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Affiliation(s)
- Isabelle Pouny
- USR CNRS-Pierre Fabre No. 3388 ETaC, Centre de Recherche et Développement Pierre Fabre, 31035 Toulouse, France
| | - Christophe Long
- USR CNRS-Pierre Fabre No. 3388 ETaC, Centre de Recherche et Développement Pierre Fabre, 31035 Toulouse, France
| | - Muriel Batut
- USR CNRS-Pierre Fabre No. 3388 ETaC, Centre de Recherche et Développement Pierre Fabre, 31035 Toulouse, France
| | - Yannick Aussagues
- USR CNRS-Pierre Fabre No. 3388 ETaC, Centre de Recherche et Développement Pierre Fabre, 31035 Toulouse, France
| | - Naubron Jean Valère
- Aix Marseille Université, CNRS, Centrale Marseille, Spectropole FR1739, 13397 Marseille, France
| | | | - Bruno David
- Pôle Actifs Végétaux, Institut de Recherche Pierre Fabre, 31035 Toulouse, France
| | - Catherine Lavaud
- Université de Reims Champagne-Ardenne, Institut de Chimie Moléculaire de Reims, UMR CNRS 7312, BP 1039, 51687 Reims, Cedex 2, France
| | - Georges Massiot
- USR CNRS-Pierre Fabre No. 3388 ETaC, Centre de Recherche et Développement Pierre Fabre, 31035 Toulouse, France
- Université de Reims Champagne-Ardenne, Institut de Chimie Moléculaire de Reims, UMR CNRS 7312, BP 1039, 51687 Reims, Cedex 2, France
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Liang Z, Gu T, Wang J, She J, Ye Y, Cao W, Luo X, Xiao J, Liu Y, Tang L, Zhou X. Chromene and chromone derivatives as liver X receptors modulators from a marine-derived Pestalotiopsis neglecta fungus. Bioorg Chem 2021; 112:104927. [PMID: 33932772 DOI: 10.1016/j.bioorg.2021.104927] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 04/13/2021] [Accepted: 04/18/2021] [Indexed: 12/30/2022]
Abstract
Four new chromene derivatives, pestalotiochromenoic acids A - D (1, 2, 4, and 5), and two new chromone derivatives, pestalotiochromones A and B (6 and 7), were obtained from the marine alga-derived fungus Pestalotiopsis neglecta SCSIO41403, as well as a reported derivate named piperochromenoic acid (3) with its configuration determined for the first time. Their structures were determined by detailed nuclear magnetic resonance (NMR) and mass spectroscopic analyses, while the absolute configurations were established by theoretical NMR and electronic circular dichroism (ECD) calculation, including Mo2(OAc)4-induced ECD experiments. Those chromene and chromone derivatives displayed weak cytotoxicity, but showed obvious liver X receptors (LXRs) modulatory activities, by in vitro tests on the expression of LXRα, LXRβ and theirtarget gene ABCA1, as well as in silico docking analysis. Moreover, the high binding affinities between pestalotiochromone A (6) and LXRα, revealed by surface plasmon resonance (SPR) with the dissociation equilibrium constant (KD) value of 6.2 μM, demonstrated 6 could act as a new potential LXR agonist.
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Affiliation(s)
- Zhi Liang
- Biopharmaceutics, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Tanwei Gu
- Biopharmaceutics, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Jianjiao Wang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, and South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Jianglian She
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, and South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Yuxiu Ye
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Nanning 530200, China
| | - Wenyu Cao
- Biopharmaceutics, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Xiaowei Luo
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Nanning 530200, China
| | - Jiao Xiao
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yonghong Liu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, and South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Lan Tang
- Biopharmaceutics, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China.
| | - Xuefeng Zhou
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, and South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
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Rojo-Portillo T, Reyes-López E, Hernández-Huerta E, Quiroz-García B, Joseph-Nathan P, Sánchez-Castellanos M, Cuétara-Guadarrama F, Cuevas G. Is the VCD spectrum a fingerprint of the conformational population? The conformation of perezone in the spotlight. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127273] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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10
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Parra Amin JE, Cuca LE, González-Coloma A. Antifungal and phytotoxic activity of benzoic acid derivatives from inflorescences of Piper cumanense. Nat Prod Res 2019; 35:2763-2771. [DOI: 10.1080/14786419.2019.1662010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | - Luis E. Cuca
- Department of Chemistry, Universidad Nacional de Colombia-sede, Bogotá, Colombia
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Souza AA, Vessecchi R, Castro-Gamboa I, Furlan M. Combined use of tandem mass spectrometry and computational chemistry to study 2H-chromenes from Piper aduncum. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:634-642. [PMID: 31144377 DOI: 10.1002/jms.4378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 05/14/2019] [Accepted: 05/17/2019] [Indexed: 06/09/2023]
Abstract
Natural 2H-chromenes were isolated from the crude extract of Piper aduncum (Piperaceae) and analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) applying collision-induced dissociation. Density functional theory (DFT) calculations were used to explain the preferred protonation sites of the 2H-chromenes based on thermochemical parameters, including atomic charges, proton affinity, and gas-phase basicity. After identifying the nucleophilic sites, the pathways were proposed to justify the formation of the diagnostic ions under ESI-MS/MS conditions. The calculated relative energy for each pathway was in good agreement with the energy-resolved plot obtained from ESI-MS/MS data. Moreover, the 2H-chromene underwent proton attachment on the prenyl moiety via a six-membered transition state. This behavior resulted in the formation of a diagnostic ion due to 2-methylpropene loss. These studies provide novel insights into gas-phase dissociation for natural benzopyran compounds, indicating how reactivity is correlated to the intrinsic acid-base equilibrium and structural aspects, including the substitution pattern on the aromatic moiety. Therefore, these results can be applied in the identification of benzopyran derivatives in a variety of biological samples.
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Affiliation(s)
- Amauri Alves Souza
- Universidade Estadual Paulista - UNESP, Instituto de Química, Rua Professor Francisco Degni, 55, Araraquara, SP, 14800-900, Brazil
| | - Ricardo Vessecchi
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, Ribeirão Preto, SP, 14040-901, Brazil
| | - Ian Castro-Gamboa
- Universidade Estadual Paulista - UNESP, Instituto de Química, Rua Professor Francisco Degni, 55, Araraquara, SP, 14800-900, Brazil
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Imperatore C, Scuotto M, Valadan M, Rivieccio E, Saide A, Russo A, Altucci C, Menna M, Ramunno A, Mayol L, Russo G, Varra M. Photo-control of cancer cell growth by benzodiazo N-substituted pyrrole derivatives. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.03.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Bünnemann K, Pollok CH, Merten C. Explicit Solvation of Carboxylic Acids for Vibrational Circular Dichroism Studies: Limiting the Computational Efforts without Losing Accuracy. J Phys Chem B 2018; 122:8056-8064. [DOI: 10.1021/acs.jpcb.8b05928] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Karoline Bünnemann
- Ruhr Universität Bochum, Lehrstuhl für Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany
| | - Corina H. Pollok
- Ruhr Universität Bochum, Lehrstuhl für Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany
| | - Christian Merten
- Ruhr Universität Bochum, Lehrstuhl für Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany
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14
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Finato AC, Fraga-Silva TF, Prati AUC, de Souza Júnior AA, Mazzeu BF, Felippe LG, Pinto RA, Golim MDA, Arruda MSP, Furlan M, Venturini J. Crude leaf extracts of Piperaceae species downmodulate inflammatory responses by human monocytes. PLoS One 2018; 13:e0198682. [PMID: 29924840 PMCID: PMC6010286 DOI: 10.1371/journal.pone.0198682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 05/23/2018] [Indexed: 02/03/2023] Open
Abstract
In this study, we aimed to evaluate the immunomodulatory effects of crude leaf extracts from Piper gaudichaudianum Kunth, P. arboreum Aub., P. umbellata L., P. fuligineum Kunth, and Peperomia obtusifolia A. Dietr. on an in vitro model of inflammatory response. The crude extracts were previously obtained by maceration of the leaves. The half-maximal inhibitory concentration was determined by the MTT assay using human peripheral blood mononuclear cells. Human monocytes were simultaneously challenged with each crude extract and lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, to induce a strong inflammatory response. After 24 h of incubation, cell-free supernatants were used for evaluating the mediators involved in inflammation: H2O2, TNF-α, IL-8, IL-6, IL-1β, IL-10, IL-12, FGF-b, and TGF-β1. We also compared the results with the effects of ketoprofen, a well-known anti-inflammatory drug. The P. gaudichaudianum crude extract downmodulated the production of H2O2, IL-1β, IL-6, IL-8, and TGF-β1 by LPS-stimulated monocytes; P. arboreum, IL-1β, IL-6, IL-8, and TNF-α; P. umbellata and P. fuligineum, H2O2, IL-1β, IL-6, IL-8, IL-10, and TNF-α; and P. obtusifolia, H2O2, IL-6, IL-8, IL-10, and TNF-α. In general, the crude leaf extracts amplified the anti-inflammatory response when compared with ketoprofen, particularly reducing the production of IL-8, a mediator involved in neutrophil recruitment during tissue damage. Thus, the crude leaf extracts of P. gaudichaudianum, P. arboreum, P. umbellata, P. fuligineum, and Peperomia obtusifolia elicited an anti-inflammatory response against LPS-challenged monocytes. These findings show the anti-inflammatory properties of these crude leaf extracts and offer new perspectives for their use in the treatment of inflammatory diseases.
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Affiliation(s)
| | - Thais Fernanda Fraga-Silva
- Universidade Estadual Paulista (Unesp), Faculdade de Ciências, Bauru, SP, Brazil
- Universidade Estadual Paulista (Unesp), Instituto de Biociências, Botucatu, SP, Brazil
| | | | | | - Bruna Fonseca Mazzeu
- Universidade Estadual Paulista (Unesp), Instituto de Química, Araraquara, SP, Brazil
| | | | - Rute Alves Pinto
- Universidade Estadual Paulista (Unesp), Instituto de Química, Araraquara, SP, Brazil
| | | | | | - Maysa Furlan
- Universidade Estadual Paulista (Unesp), Instituto de Química, Araraquara, SP, Brazil
| | - James Venturini
- Universidade Estadual Paulista (Unesp), Faculdade de Ciências, Bauru, SP, Brazil
- Universidade Federal de Mato Grosso do Sul (UFMS), Faculdade de Medicina, Campo Grande, MS, Brazil
- * E-mail:
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15
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N L Batista A, M Dos Santos F, Batista JM, Cass QB. Enantiomeric Mixtures in Natural Product Chemistry: Separation and Absolute Configuration Assignment. Molecules 2018; 23:molecules23020492. [PMID: 29473869 PMCID: PMC6017502 DOI: 10.3390/molecules23020492] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/23/2018] [Accepted: 02/21/2018] [Indexed: 01/13/2023] Open
Abstract
Chiral natural product molecules are generally assumed to be biosynthesized in an enantiomerically pure or enriched fashion. Nevertheless, a significant amount of racemates or enantiomerically enriched mixtures has been reported from natural sources. This number is estimated to be even larger since the enantiomeric purity of secondary metabolites is rarely checked in the natural product isolation pipeline. This latter fact may have drastic effects on the evaluation of the biological activity of chiral natural products. A second bottleneck is the determination of their absolute configurations. Despite the widespread use of optical rotation and electronic circular dichroism, most of the stereochemical assignments are based on empirical correlations with similar compounds reported in the literature. As an alternative, the combination of vibrational circular dichroism and quantum chemical calculations has emerged as a powerful and reliable tool for both conformational and configurational analysis of natural products, even for those lacking UV-Vis chromophores. In this review, we aim to provide the reader with a critical overview of the occurrence of enantiomeric mixtures of secondary metabolites in nature as well the best practices for their detection, enantioselective separation using liquid chromatography, and determination of absolute configuration by means of vibrational circular dichroism and density functional theory calculations.
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Affiliation(s)
- Andrea N L Batista
- Department of Chemistry, Federal University of São Carlos-UFSCar, Rod. Washington Luis s/n, km 235, São Carlos, SP 13565-905, Brazil.
| | - Fernando M Dos Santos
- Department of Chemistry, Federal University of São Carlos-UFSCar, Rod. Washington Luis s/n, km 235, São Carlos, SP 13565-905, Brazil.
| | - João M Batista
- Department of Chemistry, Federal University of São Carlos-UFSCar, Rod. Washington Luis s/n, km 235, São Carlos, SP 13565-905, Brazil.
- Institute of Science and Technology, Federal University of São Paulo-UNIFESP, R. Talim 330, São José dos Campos, SP 12231-280, Brazil.
| | - Quezia B Cass
- Department of Chemistry, Federal University of São Carlos-UFSCar, Rod. Washington Luis s/n, km 235, São Carlos, SP 13565-905, Brazil.
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16
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M. dos Santos Jr. F, Bicalho KU, Calisto ÍH, S. Scatena G, Fernandes JB, Cass QB, Batista Jr. JM. Scope of the 2(5H)-furanone helicity rule: a combined ECD, VCD, and DFT investigation. Org Biomol Chem 2018; 16:4509-4516. [DOI: 10.1039/c8ob01085d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Combination of ECD, VCD and DFT calculations revealed a possible exception to the widely used helicity rule of the 2(5H)-furanone chromophore.
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Affiliation(s)
| | - Keylla U. Bicalho
- Institute of Chemistry
- São Paulo State University – UNESP
- Araraquara
- Brazil
| | - Ítalo H. Calisto
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
| | - Gabriel S. Scatena
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
| | - João B. Fernandes
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
| | - Quezia B. Cass
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
| | - João M. Batista Jr.
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
- Institute of Science and Technology
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17
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Bünnemann K, Merten C. Solvation of a chiral carboxylic acid: effects of hydrogen bonding on the IR and VCD spectra of α-methoxyphenylacetic acid. Phys Chem Chem Phys 2017. [DOI: 10.1039/c7cp02049j] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Taking the title compound as a representative example of a chiral carboxylic acid, we investigate how its VCD spectral pattern is affected by hydrogen bonding of different solvents.
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18
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Merten C. Vibrational optical activity as probe for intermolecular interactions. Phys Chem Chem Phys 2017; 19:18803-18812. [DOI: 10.1039/c7cp02544k] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A detailed VCD spectroscopic analysis of well-selected chiral model systems can give valuable and unprecedented insights into intermolecular interactions such as solvation or reactant–substrate binding in catalysis.
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19
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Tang ZH, Liu YB, Ma SG, Li L, Li Y, Jiang JD, Qu J, Yu SS. Antiviral Spirotriscoumarins A and B: Two Pairs of Oligomeric Coumarin Enantiomers with a Spirodienone-Sesquiterpene Skeleton from Toddalia asiatica. Org Lett 2016; 18:5146-5149. [PMID: 27673343 DOI: 10.1021/acs.orglett.6b02572] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two pairs of oligomeric coumarin enantiomers, spirotriscoumarin A [(+)-1 and (-)-1] and spirotriscoumarin B [(+)-2 and (-)-2], with a spirodienone-sesquiterpene fused skeleton were isolated from Toddalia asiatica. Their structures were unambiguously established using spectroscopic data, X-ray diffraction analysis, and the electronic circular dichroism (ECD) method. The racemic mixtures (±)-1 and (±)-2 exhibit 3-to-6-fold stronger antiviral activity against influenza virus A (H3N2) (IC50: 3.13 and 2.87 μM, respectively) than their corresponding optically pure enantiomers.
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Affiliation(s)
- Zhong-Hai Tang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Yun-Bao Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Shuang-Gang Ma
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Li Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Yong Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Jian-Dong Jiang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Jing Qu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
| | - Shi-Shan Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100050, China
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20
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Costa M, Dias TA, Brito A, Proença F. Biological importance of structurally diversified chromenes. Eur J Med Chem 2016; 123:487-507. [PMID: 27494166 DOI: 10.1016/j.ejmech.2016.07.057] [Citation(s) in RCA: 183] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 06/21/2016] [Accepted: 07/23/2016] [Indexed: 12/20/2022]
Abstract
Compounds incorporating the chromene scaffold are largely present in natural products and display a wide variety of biological activities. Their low toxicity combined to the broad pharmacological properties have inspired medicinal chemists in the search for new therapeutic agents. This review covers the literature between 1993 and on the biological activity of 2H- and 4H-chromenes, both from natural and synthetic origin. Includes a section that identifies a selection of chromene-based natural products, followed by recent literature on bioactive natural chromenes and the corresponding source, covering plants and fruits. Synthetic chromenes are equally important and a separate section addresses the use of these derivatives as new leads for drug discovery. Different biological targets were identified, namely those associated with anticancer, antimicrobial, anti-inflammatory, antithrombotic and antipsychotic activities.
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Affiliation(s)
- Marta Costa
- Life and Health Sciences Research Institute (ICVS), University of Minho, Campus of Gualtar, Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Tatiana A Dias
- Department of Chemistry, University of Minho, Campus of Gualtar, Braga, Portugal
| | - Alexandra Brito
- Department of Chemistry, University of Minho, Campus of Gualtar, Braga, Portugal
| | - Fernanda Proença
- Department of Chemistry, University of Minho, Campus of Gualtar, Braga, Portugal.
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21
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da Silva A Maciel D, Freitas VP, Conserva GAA, Alexandre TR, Purisco SU, Tempone AG, Melhem MSC, Kato MJ, Guimarães EF, Lago JHG. Bioactivity-guided isolation of laevicarpin, an antitrypanosomal and anticryptococcal lactam from Piper laevicarpu (Piperaceae). Fitoterapia 2016; 111:24-8. [PMID: 27083380 DOI: 10.1016/j.fitote.2016.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 04/06/2016] [Accepted: 04/08/2016] [Indexed: 12/20/2022]
Abstract
Crude CH2Cl2 extract from leaves of Piper laevicarpu (Piperaceae) displayed antitrypanosomal activity against trypomastigote forms of Trypanosoma cruzi (Y strain) and antimicrobial potential against Cryptococcus gattii (strain-type WM 178). Bioactivity-guided fractionation of crude extract afforded one new natural bioactive lactam derivative, named laevicarpin. The structure of isolated compound, which displayed a very rare ring system, was elucidated based on NMR, IR and MS spectral analysis. Using MTT assay, the trypomastigotes of T. cruzi demonstrated susceptibility to laevicarpin displaying IC50 value of 14.7μg/mL (49.6μM), about 10-fold more potent than the standard drug benznidazole. The mammalian cytotoxicity of laevicarpin was verified against murine fibroblasts (NCTC cells) and demonstrated a CC50 value of 100.3μg/mL (337.7μM-SI=7). When tested against Cryptococcus gattii, laevicarpin showed an IC50 value of 2.3μg/mL (7.9μM) and a MIC value of 7.4μg/mL (25μM). Based in the obtained results, laevicarpin could be used as a scaffold for future drug design studies against the Chagas disease and anti-cryptococosis agents.
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Affiliation(s)
- Dayany da Silva A Maciel
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, 09972-270, São Paulo, SP, Brazil
| | - Viviane P Freitas
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, 09972-270, São Paulo, SP, Brazil
| | - Geanne A Alves Conserva
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, 09972-270, São Paulo, SP, Brazil
| | - Tatiana R Alexandre
- Centro de Parasitologia e Micologia, Instituto Adolfo Lutz, 01246-000, São Paulo, SP, Brazil
| | - Sonia U Purisco
- Centro de Parasitologia e Micologia, Instituto Adolfo Lutz, 01246-000, São Paulo, SP, Brazil
| | - Andre G Tempone
- Centro de Parasitologia e Micologia, Instituto Adolfo Lutz, 01246-000, São Paulo, SP, Brazil
| | - Márcia Souza C Melhem
- Centro de Parasitologia e Micologia, Instituto Adolfo Lutz, 01246-000, São Paulo, SP, Brazil
| | - Massuo J Kato
- Instituto de Química, Universidade de São Paulo, 05508-000, São Paulo, SP, Brazil
| | - Elsie F Guimarães
- Instituto de Pesquisas do Jardim Botânico, 22460-030, Rio de Janeiro, RJ, Brazil
| | - João Henrique G Lago
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, 09972-270, São Paulo, SP, Brazil.
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22
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Junior FMS, Covington CL, de Albuquerque ACF, Lobo JFR, Borges RM, de Amorim MB, Polavarapu PL. Absolute Configuration of (-)-Centratherin, a Sesquiterpenoid Lactone, Defined by Means of Chiroptical Spectroscopy. JOURNAL OF NATURAL PRODUCTS 2015; 78:2617-2623. [PMID: 26565920 DOI: 10.1021/acs.jnatprod.5b00546] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
(-)-Centratherin is a bioactive sesquiterpenoid lactone, whose absolute configuration (AC) was not established, but has been proposed based on those of germacrane precursors. To verify this proposal, the experimental electronic circular dichroism (ECD), electronic dissymmetry factor (EDF), optical rotatory dispersion (ORD), vibrational circular dichroism (VCD), and vibrational dissymmetry factor (VDF) spectra of (-)-centratherin have been analyzed with the corresponding density functional theoretical predictions. These analyses suggest the AC of naturally occurring (-)-centratherin to be (6R,7R,8S,10R,2'Z).
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Affiliation(s)
- Fernando M S Junior
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro , 21941-902, Rio de Janeiro, RJ, Brazil
- Department of Chemistry, Vanderbilt University , Nashville, Tennessee 37235, United States
| | - Cody L Covington
- Department of Chemistry, Vanderbilt University , Nashville, Tennessee 37235, United States
| | - Ana Carolina F de Albuquerque
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro , 21941-902, Rio de Janeiro, RJ, Brazil
| | - Jonathas F R Lobo
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro , 21941-902, Rio de Janeiro, RJ, Brazil
| | - Ricardo M Borges
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro , 21941-902, Rio de Janeiro, RJ, Brazil
| | - Mauro B de Amorim
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro , 21941-902, Rio de Janeiro, RJ, Brazil
| | - Prasad L Polavarapu
- Department of Chemistry, Vanderbilt University , Nashville, Tennessee 37235, United States
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23
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Gacesa R, Dunlap WC, Long PF. Bioinformatics analyses provide insight into distant homology of the Keap1-Nrf2 pathway. Free Radic Biol Med 2015; 88:373-380. [PMID: 26117326 DOI: 10.1016/j.freeradbiomed.2015.06.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 06/03/2015] [Accepted: 06/06/2015] [Indexed: 12/25/2022]
Abstract
An essential requirement for the evolution of early eukaryotic life was the development of effective means to protect against metabolic oxidative stress and exposure to environmental toxicants. In present-day mammals, the master transcription factor Nrf2 regulates basal level homeostasis and inducible expression of numerous detoxifying and antioxidant genes. To examine early evolution of the Keap1-Nrf2 pathway, we present bioinformatics analyses of distant homology of mammalian Keap1 and Nrf2 proteins across the Kingdoms of Life. Software written for this analysis is made freely available on-line. Furthermore, utilizing protein modeling and virtual screening methods, we demonstrate potential for Nrf2 activation by competitive inhibition of its binding to Keap1, specifically by UV-protective fungal mycosporines and marine mycosporine-like amino acids (MAAs). We contend that coevolution of Nrf2-activating secondary metabolites by fungi and other extant microbiota may provide prospective compound leads for the design of new therapeutics to target activation of the human Keap1-Nrf2 pathway for treating degenerative diseases of ageing.
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Affiliation(s)
- Ranko Gacesa
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London SE1 9NH, UK
| | - Walter C Dunlap
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London SE1 9NH, UK
| | - Paul F Long
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London SE1 9NH, UK; Department of Chemistry, King's College London, 150 Stamford Street, London SE1 9NH, UK.
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24
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Hans M, Charpentier M, Huch V, Jauch J, Bruhn T, Bringmann G, Quandt D. Stereoisomeric Composition of Natural Myrtucommulone A. JOURNAL OF NATURAL PRODUCTS 2015; 78:2381-2389. [PMID: 26457652 DOI: 10.1021/acs.jnatprod.5b00358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Myrtucommulone A (MC A) (1), isolated from Myrtus communis (myrtle), shows the same pharmacological activity for inhibition of inflammation and induction of apoptosis as synthetic MC A, which consists of three stereoisomers, i.e., two enantiomers and one meso form. This led to the question of whether the natural MC A is a pure stereoisomer or a mixture of stereoisomers. The specific rotation and electronic circular dichroism (ECD) data of natural MC A (1) as well as of a pentacyclic derivative 4 revealed that naturally occurring MC A (1) consists of the racemate and the meso form in a 1:1 ratio. A probable precursor of MC A (1), nor-semimyrtucommulone (5), was also isolated from myrtle as a racemate. The absolute configurations of the enantiomers of 1 and 5 were determined using a combination of experimental and quantum-chemical calculated ECD spectra.
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Affiliation(s)
- Marcus Hans
- Institute of Organic Chemistry, Saarland University , Campus C 4.2, 66123 Saarbrücken, Germany
| | - Maël Charpentier
- Institute of Organic Chemistry, Saarland University , Campus C 4.2, 66123 Saarbrücken, Germany
| | - Volker Huch
- Institute of Inorganic Chemistry, Saarland University , Campus C 4.1, 66123 Saarbrücken, Germany
| | - Johann Jauch
- Institute of Organic Chemistry, Saarland University , Campus C 4.2, 66123 Saarbrücken, Germany
| | - Torsten Bruhn
- Institute of Organic Chemistry, University of Würzburg , Am Hubland, 97074 Würzburg, Germany
| | - Gerhard Bringmann
- Institute of Organic Chemistry, University of Würzburg , Am Hubland, 97074 Würzburg, Germany
| | - Dietmar Quandt
- Nees-Institute for Biodiversity of Plants, University of Bonn , Meckenheimer Allee 170, 53115 Bonn, Germany
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25
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Batista Jr. JM, Blanch EW, Bolzani VDS. Recent advances in the use of vibrational chiroptical spectroscopic methods for stereochemical characterization of natural products. Nat Prod Rep 2015; 32:1280-302. [DOI: 10.1039/c5np00027k] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A comprehensive look into application of vibrational optical activity methods for conformational and configurational assignments in natural product molecules over the last 15 years is provided.
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Affiliation(s)
- João M. Batista Jr.
- Department of Chemistry
- Federal University of São Carlos – UFSCar
- São Carlos
- Brazil
| | - Ewan W. Blanch
- School of Applied Sciences
- RMIT University
- Melbourne
- Australia
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26
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Gaia AM, Yamaguchi LF, Jeffrey CS, Kato MJ. Age-dependent changes from allylphenol to prenylated benzoic acid production in Piper gaudichaudianum Kunth. PHYTOCHEMISTRY 2014; 106:86-93. [PMID: 25041698 DOI: 10.1016/j.phytochem.2014.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/30/2014] [Accepted: 05/31/2014] [Indexed: 05/24/2023]
Abstract
HPLC-DAD and principal component analysis (PCA) of the (1)H NMR spectrum of crude plant extracts showed high chemical variability among seedlings and adult organs of Piper gaudichaudianum. While gaudichaudianic acid was the major compound in the adult leaves, apiole and dillapiole were the major compounds in their seedling leaves. By the 15th month of seedling growth, the levels of apiole and dillapiole decreased and gaudichaudianic acid appeared along with two compounds, biosynthetically related to gaudichaudianic acid.
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Affiliation(s)
- Anderson M Gaia
- Research Support Center in Molecular Diversity of Natural Products, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, 05508-000 São Paulo, SP, Brazil
| | - Lydia F Yamaguchi
- Research Support Center in Molecular Diversity of Natural Products, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, 05508-000 São Paulo, SP, Brazil
| | | | - Massuo J Kato
- Research Support Center in Molecular Diversity of Natural Products, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, 05508-000 São Paulo, SP, Brazil.
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27
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Zhu H, Huan L, Chen C, Yang J, He J, Chen Y, Yao G, Luo Z, Xue Y, Zhang Y. A pair of unprecedented cyclohexylethanoid enantiomers containing unusual trioxabicyclo[4.2.1]nonane ring from Clerodendrum bungei. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.02.088] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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28
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Jeffrey CS, Leonard MD, Glassmire AE, Dodson CD, Richards LA, Kato MJ, Dyer LA. Antiherbivore prenylated benzoic acid derivatives from Piper kelleyi. JOURNAL OF NATURAL PRODUCTS 2014; 77:148-153. [PMID: 24422717 DOI: 10.1021/np400886s] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The known prenylated benzoic acid derivative 3-geranyl-4-hydroxy-5-(3″,3″-dimethylallyl)benzoic acid (1) and two new chromane natural products were isolated from the methanolic extract of the leaves of Piper kelleyi Tepe (Piperaceae), a midcanopy tropical shrub that grows in lower montane rain forests in Ecuador and Peru. Structure determination using 1D and 2D NMR analysis led to the structure of the chromene 2 and to the reassignment of the structure of cumanensic acid as 4, an isomeric chromene previously isolated from Piper gaudichaudianum. The structure and relative configuration of new chromane 3 was determined using 1D and 2D NMR spectroscopic analysis and was found to be racemic by ECD spectropolarimetry. The biological activity of 1-3 was evaluated against a lab colony of the generalist caterpillar Spodoptera exigua (Noctuidae), and low concentrations of 2 and 3 were found to significantly reduce fitness. Further consideration of the biosynthetic relationship of the three compounds led to the proposal that 1 is converted to 2 via an oxidative process, whereas 3 is produced through hetero-[4+2] dimerization of a quinone methide derived from the chromene 2.
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Affiliation(s)
- Christopher S Jeffrey
- Department of Chemistry, University of Nevada, Reno , Reno, Nevada 89557, United States
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29
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Sherer EC, Lee CH, Shpungin J, Cuff JF, Da C, Ball R, Bach R, Crespo A, Gong X, Welch CJ. Systematic approach to conformational sampling for assigning absolute configuration using vibrational circular dichroism. J Med Chem 2014; 57:477-94. [PMID: 24383452 DOI: 10.1021/jm401600u] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Systematic methods that speed-up the assignment of absolute configuration using vibrational circular dichrosim (VCD) and simplify its usage will advance this technique into a robust platform technology. Applying VCD to pharmaceutically relevant compounds has been handled in an ad hoc fashion, relying on fragment analysis and technical shortcuts to reduce the computational time required. We leverage a large computational infrastructure to provide adequate conformational exploration which enables an accurate assignment of absolute configuration. We describe a systematic approach for rapid calculation of VCD/IR spectra and comparison with corresponding measured spectra and apply this approach to assign the correct stereochemistry of nine test cases. We suggest moving away from the fragment approach when making VCD assignments. In addition to enabling faster and more reliable VCD assignments of absolute configuration, the ability to rapidly explore conformational space and sample conformations of complex molecules will have applicability in other areas of drug discovery.
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Affiliation(s)
- Edward C Sherer
- Merck Research Laboratories, Merck & Co., Inc., PO Box 2000, Rahway, New Jersey 07065, United States
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30
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Batista JM, da Silva Bolzani V. Determination of the Absolute Configuration of Natural Product Molecules Using Vibrational Circular Dichroism. STUDIES IN NATURAL PRODUCTS CHEMISTRY 2014. [DOI: 10.1016/b978-0-444-63294-4.00013-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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31
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Wilde F, Chamseddin C, Lemmerhirt H, Bednarski PJ, Jira T, Link A. Evaluation of (S)- and (R)-misonidazole as GPX inhibitors: synthesis, characterization including circular dichroism and in vitro testing on bovine GPx-1. Arch Pharm (Weinheim) 2013; 347:153-60. [PMID: 24375829 DOI: 10.1002/ardp.201300285] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 09/24/2013] [Accepted: 09/24/2013] [Indexed: 11/06/2022]
Abstract
Racemic misonidazole, a radiosensitizer formally used in radiation therapy of cancer and to date still applied, was once reported to exhibit strong inhibitory effects on mouse glutathione peroxidases (GPX). This appeared to qualify misonidazole as a lead structure for the development of novel GPX inhibitors to cause oxidative stress in chemotherapy-resistant tumors. A unique feature of misonidazole as an inhibitor of GPX is the absence of a thiol functionality. Therefore, it was expected to selectively target inhibition devoid of promiscuous interactions with cations and sulfhydryl groups. We synthesized the isomers of misonidazole and analyzed the ability of chiroptical high-performance liquid chromatography (HPLC) to identify the particular enantiomers. Due to the chiral pool synthesis, the assignment of the correct configuration could be verified. Finally, we evaluated both isomers for their inhibitory activities on bovine erythrocyte GPx-1, which is 87% homologous to the human enzyme. Despite the previously reported inhibition of racemic misonidazole on the less homologous mouse GPx-1, we did not find any significant inhibitory activity on the bovine enzyme for either isomer. Though misonidazole appears unlikely to be an inhibitor of human GPx-1 activity, we still spotlight misonidazole as a promising fragment-like lead structure in general.
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Affiliation(s)
- Felix Wilde
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany
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Yin G, Zhang R, Li L, Tian J, Chen L. One-Pot Enantioselective Synthesis of 3-Nitro-2H-chromenes Catalyzed by a Simple 4-Hydroxyprolinamide with 4-Nitrophenol as Cocatalyst. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300505] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Li S, Ni S, Wu L, Li L, Jiang B, Wang H, Sun G, Gan M, Li J, He W, Lin L, Wang Y, Bai S, Si S. 19-[(1'S,4'R)-4'-Hydroxy-1'-methoxy-2'-oxopentyl]geldanamycin, a natural geldanamycin analogue from Streptomyces hygroscopicus 17997. JOURNAL OF NATURAL PRODUCTS 2013; 76:969-973. [PMID: 23656556 DOI: 10.1021/np4000679] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A novel natural geldanamycin analogue was discovered in Streptomyces hygroscopicus 17997. Its 4,5-dihydro form was also identified in the gdmP gene disruption mutant of Streptomyces hygroscopicus 17997. The structures of the two compounds were determined to be 19-[(1'S,4'R)-4'-hydroxy-1'-methoxy-2'-oxopentyl]geldanamycin (1) and 19-[(1'S,4'R)-4'-hydroxy-1'-methoxy-2'-oxopentyl]-4,5-dihydrogeldanamycin (2), respectively, by extensive spectroscopic data analysis, including 2D NMR, modified Mosher's method, and electronic circular dichroism. Compared to geldanamycin, 1 and 2 showed increased water solubility and decreased cytotoxicity against HepG2 cells.
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Affiliation(s)
- Shufen Li
- Key Laboratory of Biotechnology of Antibiotics of Ministry of Health, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
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Advantages of electronic circular dichroism detection for the stereochemical analysis and characterization of drugs and natural products by liquid chromatography. J Chromatogr A 2012; 1269:69-81. [PMID: 23040981 DOI: 10.1016/j.chroma.2012.09.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/10/2012] [Accepted: 09/17/2012] [Indexed: 11/21/2022]
Abstract
The need for analytical methods for the determination of the enantiomeric excess of chiral compounds increased significantly in the last decades, and enantioselective separation techniques resulted particularly efficient to this purpose. Moreover, when detection systems based on chiroptical properties (optical rotation or circular dichroism) are employed in high-performance liquid chromatography (HPLC), the stereochemistry of a chiral analyte can be fully determined. Indeed, the coupling of HPLC with chiroptical detection systems allows the simultaneous assessment of the absolute configuration of stereoisomers and the evaluation of the enantiomeric/diastereomeric excess of samples. These features are particularly important in the study of drugs and natural products provided with biological activity, because the assignment of their absolute stereochemistry is essential to establish reliable structure-activity relationships. The following review aims to discuss the analytical advantages arising from the employment of electronic circular dichroism (ECD) detection systems in stereochemical analysis by HPLC upon chiral and non-chiral stationary phases and their use for the stereochemical characterization of chiral drugs and natural compounds. The different methods for the correlation between absolute stereochemistry and chiroptical properties are critically discussed. Relevant HPLC applications of ECD detection systems are then reported, and their analytical advantages are highlighted. For instance, the importance of the concentration-independent anisotropy factor (g-factor; g=Δɛ/ɛ) for the determination of the stereoisomeric composition of samples upon non-chiral stationary phases is underlined, since its sensitivity makes ECD detection very well suited for the enantioselective analysis of large libraries of chiral compounds in relatively short times.
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de Oliveira A, Mesquita JT, Tempone AG, Lago JHG, Guimarães EF, Kato MJ. Leishmanicidal activity of an alkenylphenol from Piper malacophyllum is related to plasma membrane disruption. Exp Parasitol 2012; 132:383-7. [PMID: 22981719 DOI: 10.1016/j.exppara.2012.08.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 08/10/2012] [Accepted: 08/28/2012] [Indexed: 11/17/2022]
Abstract
Leishmaniasis and Chagas disease are parasitic protozoan infections that affect the poorest population in the world, causing high mortality and morbidity. As a result of highly toxic and long-duration treatments, novel, safe and more efficacious drugs are essential. In this work, the methanol (MeOH) extract from the leaves of Piper malacophyllum (Piperaceae) was fractioned to afford one alkenylphenol, which was characterized as 4-[(3'E)-decenyl]phenol (gibbilimbol B) by spectroscopic methods. Anti-protozoan in vitro assays demonstrated for the first time that Leishmania (L.) infantum chagasi was susceptible to gibbilimbol B, with an in vitro EC(50) of 23 μg/mL against axenic promastigotes and an EC(50) of 22 μg/mL against intracellular amastigotes. Gibbilimbol B was also tested for anti-trypanosomal activity (Trypanosoma cruzi) and showed an EC(50) value of 17 μg/mL against trypomastigotes. To evaluate the cytotoxic parameters, this alkenylphenol was tested in vitro against NCTC cells, showing a CC(50) of 59 μg/mL and absent hemolytic activity at the highest concentration of 75 μg/mL. Using the fluorescent probe SYTOX Green suggested that the alkenylphenol disrupted the Leishmania plasma membrane upon initial incubation. Further drug design studies aiming at derivatives could be a promising tool for the development of new therapeutic agents for leishmaniasis and Chagas disease.
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Affiliation(s)
- Alberto de Oliveira
- Instituto de Química, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
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Felippe LG, Batista JM, Baldoqui DC, Nascimento IR, Kato MJ, He Y, Nafie LA, Furlan M. VCD to determine absolute configuration of natural product molecules: secolignans from Peperomia blanda. Org Biomol Chem 2012; 10:4208-14. [PMID: 22543980 DOI: 10.1039/c2ob25109d] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The absolute configuration and solution-state conformers of three peperomin-type secolignans isolated from Peperomia blanda (Piperaceae) are unambiguously determined by using vibrational circular dichroism (VCD) spectroscopy associated with density functional theory (DFT) calculations. Advantages of VCD over the electronic form of CD for the analysis of diastereomers are also discussed. This work extends our growing knowledge about secondary metabolites within the Piperaceae family species while providing a definitive and straightforward method to assess the absolute stereochemistry of secolignans.
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Affiliation(s)
- Lidiane G Felippe
- Organic Chemistry Department, Institute of Chemistry, São Paulo State University - UNESP, Araraquara, SP 14800-900, Brazil
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Dragna J, Pescitelli G, Tran L, Lynch VM, Anslyn EV, Di Bari L. In situ assembly of octahedral Fe(II) complexes for the enantiomeric excess determination of chiral amines using circular dichroism spectroscopy. J Am Chem Soc 2012; 134:4398-407. [PMID: 22272943 PMCID: PMC3329375 DOI: 10.1021/ja211768v] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A method for discriminating between α-chiral primary amine enantiomers is reported. The method utilizes circular dichroism (CD) spectroscopy and a sensing ensemble composed of 2-formyl-3-hydroxypyridine (4) and Fe(II)(TfO)(2). Aldehyde 4 reacts rapidly with chiral amines to form chiral imines, which complex Fe(II) to form a series of diastereomeric octahedral complexes that are CD-active in both the UV and visible regions of the spectrum. NMR studies showed that for enantiomerically pure imine complexes, the Δ-fac isomer is preferred. A statistical analysis of the distribution of stereoisomers accurately modeled the calibration curves for enantiomeric excess (ee). CD signals appearing in the UV region were bisignate, and the nulls of the CD signals were coincident with maxima in the UV spectrum, consistent with exciton coupling. Time-dependent density functional theory and semiempirical calculations confirmed that the CD signals in the UV region arise from coupling of the π-π* transitions in the imine chromophores and that they can be used to describe the signs and magnitudes of the curves accurately. The CD signals in the visible region arise from metal-to-ligand charge-transfer bands, and these signals can be used to determine the ee values of chiral amines with an average absolute error of ±5%. Overall, the strategy presented herein represents a facile in situ assembly process that uses commercially available simple reagents to create large optical signals indicative of ee values.
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Affiliation(s)
- Justin Dragna
- Department of Chemistry and Biochemistry The University of Texas Austin TX 78712
- Dipartimento di Chimica e Chimica Industriale Via Risorgimento 35 1-56126 PISA (Italy)
| | - Gennaro Pescitelli
- Department of Chemistry and Biochemistry The University of Texas Austin TX 78712
- Dipartimento di Chimica e Chimica Industriale Via Risorgimento 35 1-56126 PISA (Italy)
| | - Lee Tran
- Department of Chemistry and Biochemistry The University of Texas Austin TX 78712
- Dipartimento di Chimica e Chimica Industriale Via Risorgimento 35 1-56126 PISA (Italy)
| | - Vincent M. Lynch
- Department of Chemistry and Biochemistry The University of Texas Austin TX 78712
- Dipartimento di Chimica e Chimica Industriale Via Risorgimento 35 1-56126 PISA (Italy)
| | | | - Lorenzo Di Bari
- Department of Chemistry and Biochemistry The University of Texas Austin TX 78712
- Dipartimento di Chimica e Chimica Industriale Via Risorgimento 35 1-56126 PISA (Italy)
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