Mechanism of the Pechmann Reaction: A Theoretical Study

Daru, János; Stirling, András

doi:10.1021/jo201439u

Cited by 48 publications

(32 citation statements)

References 37 publications

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“…15 In 1935, Appel first noticed that 1-naphthols react with β-keto esters far more easily than 2-naphthols. The ring formation involves the initial trans-esterification, followed by nucleophilic attack of the naphthol ring at the carbonyl group, and subsequent dehydration.…”

Section: Synthesis Through the Pechmann Reactionmentioning

confidence: 99%

π-Expanded coumarins: synthesis, optical properties and applications

et al. 2015

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Coumarins fused with other aromatic units have recently emerged as a hot topic of research. Their synthesis is partly based on classical methodologies such as Pechmann reaction or Knoevenagel condensation, but it also sparked the discovery of completely new pathways. In very recent years so-called vertically-expanded coumarins were synthesized, effectively expanding the portfolio of existing architectures. A subtle relationship exists between the structure of fused coumarins and their optical properties. Although absorption of UV-radiation and light is unifying theme among these π-expanded coumarins, the fluorescence properties strongly depend on the structure. The mode of fusion, the type of additional ring and the presence of electron-donating and electron-withdrawing substituents all influence the photophysical parameters. Recent advances made it possible to modulate their absorption from 300 nm to 550 nm, resulting in new coumarins emitting orange light. This review serves as a guide through both synthesis strategies and structure-property relationship nuances. Strong intramolecular charge-transfer character made it possible to reach suitable values of two-photon absorption crosssection. Photophysical advantages of π-expanded coumarins have been already utilized in fluorescence probes and two-photon excited fluorescence microscopy.

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Section: Synthesis Through the Pechmann Reactionmentioning

confidence: 99%

π-Expanded coumarins: synthesis, optical properties and applications

et al. 2015

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“…Coumarins and derivatives are structural units present in several natural products (Daru and Stirling 2011;Kalita and Kumar 2012), obtained by plant extraction (Bertin et al 2014) or by microbial synthesis. More than 1300 coumarins have been identified as secondary metabolites from plants, bacteria, and fungi (Hwang et al 2013;Venugopala et al 2013;Wang et al 2013;Islam et al 2015).…”

Section: Introductionmentioning

confidence: 99%

“…The simplicity and versatility of the coumarin molecule makes it an interesting starting point for a wide range of applications (Matos et al 2015). They are used as technological potential in pharmaceutical, agrochemical, fragrance industries, food, cosmetic industry, and in color technology as optical brightening agents or laser dyes (Daru and Stirling 2011;Santos et al 2013;Venugopala et al 2013;Vekariya and Patel 2014). Coumarins constitute the largest class of fluorescent dyes (Martins et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Fungi as a source of natural coumarins production

Costa

Tavares

Oliveira

2016

Appl Microbiol Biotechnol

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Natural coumarins and derivatives are compounds that occur naturally in several organisms (plant, bacteria, and fungi) consisting of fused benzene and α-pyrone rings. These compounds show high technological potential applications in agrochemical, food, pharmaceuticals, and cosmetics industries. Therefore, the need for bulk production of coumarins and the advancement of the chemical and pharmaceutical industries led to the development of synthetic coumarin. However, biotransformation process, synthetic bioengineering, metabolic engineering, and bioinformatics have proven effective in the production of natural products. Today, these biological systems are recognized as green chemistry innovation and business strategy. This review article aims to report the potential of fungi for synthesis of coumarin. These microorganisms are described as a source of natural products capable of synthesizing many bioactive metabolites. The features, classification, properties, and industrial applications of natural coumarins as well as new molecules obtained by basidiomycetes and ascomycetes fungi are reported in order to explore a topic not yet discussed in the scientific literature.

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“…The Pechmann reaction is one of the most widely applied synthetic routes for coumarin derivatives (Daru and Stirling, 2011; Kalita and Kumar, 2012). It involves the condensation of phenols with β-ketoesters under acid-catalyzed conditions, which proceeds via electrophilic attack, trans-esterification, and dehydration.…”

Section: Resultsmentioning

confidence: 99%

Synthesis and photochemical properties of PEGylated coumarin-caged ceramides for cell studies

Kim

Day

Lirette

et al. 2016

Chemistry and Physics of Lipids

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Caged ceramide analogues (C6-, C16-, C18-, C22- and C24-Cer) have been prepared by introducing a hydrophilic coumarin-based cage bearing a short polyethylene glycol (PEG) chain. (6-Bromo-7-mTEGylated-coumarin-4-yl)methyl (Btc) caged ceramide showed efficient photo-uncaging to release the parent ceramide upon direct exposure to 350 nm UV light; in contrast (7-mTEGylated-coumarin-4-yl) methyl (Tc) caged ceramide was photolysed more slowly. In preliminary experiments, Btc-caged ceramides were taken up by cells and their photolysis led to decreases in cell viability, but not to activation of caspase enzymes, suggesting that either reactive oxygen species or an alternate caspase-independent pathway may be responsible for the decreases in cell viability caused by photolysis of caged ceramides.

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Mechanism of the Pechmann Reaction: A Theoretical Study

Cited by 48 publications

References 37 publications

π-Expanded coumarins: synthesis, optical properties and applications

π-Expanded coumarins: synthesis, optical properties and applications

Fungi as a source of natural coumarins production

Synthesis and photochemical properties of PEGylated coumarin-caged ceramides for cell studies

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