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Journal articles on the topic 'Lactones'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

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1

Faizullina, Lily Kh, Yulia A. Khalilova, Artur R. Tagirov, et al. "Evaluation of fungicidal, bactericidal and anti-tumor activities of lactones of medium and large sizes of cycles obtained from levoglucosenone." Butlerov Communications 59, no. 9 (2019): 100–105. http://dx.doi.org/10.37952/roi-jbc-01/19-59-9-100.

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Medium and large lactones attract the attention of chemists by the uniqueness of their structure, versatile biological activity and limited availability. Among the secondary metabolites of this group, β-lactones are more common, then γ- and δ-lactones, classical and non-classical macrolides, polyene antibiotics, spiro-macrolides and macrolactones. On the basis of many lactones, important preparations of the most diverse pharmacological action have been obtained. Earlier, we proposed a 3-stage scheme for the synthesis of chiral lactones of medium and large size based on levoglucosenone. The lac

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2

Schaefer, Amy L., Terumi A. Taylor, J. Thomas Beatty, and E. P. Greenberg. "Long-Chain Acyl-Homoserine Lactone Quorum-Sensing Regulation of Rhodobacter capsulatus Gene Transfer Agent Production." Journal of Bacteriology 184, no. 23 (2002): 6515–21. http://dx.doi.org/10.1128/jb.184.23.6515-6521.2002.

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ABSTRACT Many proteobacteria use acyl-homoserine lactones as quorum-sensing signals. Traditionally, biological detection systems have been used to identify bacteria that produce acyl-homoserine lactones, although the specificities of these detection systems can limit discovery. We used a sensitive approach that did not require a bioassay to detect production of long-acyl-chain homoserine lactone production by Rhodobacter capsulatus and Paracoccus denitrificans. These long-chain acyl-homoserine lactones are not readily detected by standard bioassays. The most abundant acyl-homoserine lactone wa

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3

Ulrich, Ricky L. "Quorum Quenching: Enzymatic Disruption of N-Acylhomoserine Lactone-Mediated Bacterial Communication in Burkholderia thailandensis." Applied and Environmental Microbiology 70, no. 10 (2004): 6173–80. http://dx.doi.org/10.1128/aem.70.10.6173-6180.2004.

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ABSTRACT Many species of gram-negative bacteria communicate by synthesizing, secreting, and responding to N-acylhomoserine lactones (AHLs), a mechanism termed quorum sensing. Several investigations have characterized numerous AHL-degrading enzymes (AiiA lactonases) encoded by environmental isolates of Bacillus spp. The Burkholderia thailandensis quorum system is comprised of at least three AHL synthases (AHSs) and five transcriptional regulators belonging to the LuxIR class of proteins. Expression of the Bacillus anthracis (Ames strain) AiiA lactonase in B. thailandensis completely abolished t

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4

Cambie, Richard C., Lorna H. Mitchell, and Peter S. Rutledge. "Acid-Promoted Fries Rearrangements of Benzannulated Lactones." Australian Journal of Chemistry 51, no. 12 (1998): 1167. http://dx.doi.org/10.1071/c98023.

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The scope of acid-promoted Fries rearrangements of benzannulated lactones has been examined. The reaction is applicable to seven-membered lactones possessing a sufficiently activated aromatic ring but not to six-membered lactones, and it proceeds in higher yield for diterpenoid lactones than for lower molecular weight lactones. The structures of the 2,6-methano-bridged benzoxocin side products (23), (24), and (25) from rearrangement of the diterpenoid lactone (11) have been assigned.

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5

Surowiak, Alicja K., Lucyna Balcerzak, Stanisław Lochyński, and Daniel J. Strub. "Biological Activity of Selected Natural and Synthetic Terpenoid Lactones." International Journal of Molecular Sciences 22, no. 9 (2021): 5036. http://dx.doi.org/10.3390/ijms22095036.

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Terpenoids with lactone moieties have been indicated to possess high bioactivity. Certain terpenoid lactones exist in nature, in plants and animals, but they can also be obtained by chemical synthesis. Terpenoids possessing lactone moieties are known for their cytotoxic, anti-inflammatory, antimicrobial, anticancer, and antimalarial activities. Moreover, one terpenoid lactone, artemisinin, is used as a drug against malaria. Because of these abilities, there is constant interest in new terpenoid lactones that are both isolated and synthesized, and their biological activities have been verified.

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Klinotová, Eva, Václav Křeček, Jiří Klinot та ін. "An unusual reaction of a bridged triterpenoid α-diketone with acetic anhydride". Collection of Czechoslovak Chemical Communications 56, № 12 (1991): 2917–35. http://dx.doi.org/10.1135/cccc19912917.

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3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb.

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7

Bergonzi, Celine, Michael Schwab, Eric Chabriere, and Mikael Elias. "The quorum-quenching lactonase from Alicyclobacter acidoterrestris: purification, kinetic characterization, crystallization and crystallographic analysis." Acta Crystallographica Section F Structural Biology Communications 73, no. 8 (2017): 476–80. http://dx.doi.org/10.1107/s2053230x17010640.

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Lactonases comprise a class of enzymes that hydrolyze lactones, including acyl-homoserine lactones (AHLs); the latter are used as chemical signaling molecules by numerous Gram-negative bacteria. Lactonases have therefore been demonstrated to quench AHL-based bacterial communication. In particular, lactonases are capable of inhibiting bacterial behaviors that depend on these chemicals, such as the formation of biofilms or the expression of virulence factors. A novel representative from the metallo-β-lactamase superfamily, named AaL, was isolated from the thermoacidophilic bacterium Alicyclobact

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8

Kovács, Balázs, Péter Püski, Ákos Bajtel, et al. "Targeted Screening and Quantification of Characteristic Sesquiterpene Lactones in Ambrosia artemisiifolia L. at Different Growth Stages." Plants 13, no. 15 (2024): 2053. http://dx.doi.org/10.3390/plants13152053.

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Sesquiterpene lactones are specialized plant metabolites with promising pharmacological activities. These metabolites are characteristic marker compounds for the aerial parts of Ambrosia artemisiifolia. Numerus sesquiterpene lactones have been isolated from ragweed; however, there is no information on their bioproduction and quantification throughout the life cycle of the plant. The sesquiterpene lactone content of ragweed samples collected in Szeged and Nyíri was analyzed using HPLC. Significant differences in the amount and bioproduction rhythm of sesquiterpene lactones were found between th

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9

Gładkowski, Witold. "TRZYMYWANIE I WŁAŚCIWOŚCI BIOLOGICZNE RACEMICZNYCH I OPTYCZNIE CZYNNYCH LAKTONÓW Z PIERŚCIENIEM AROMATYCZNYM W POZYCJI β". Wiadomości Chemiczne 77, № 5 (2023): 509–31. https://doi.org/10.53584/wiadchem.2023.05.5.

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Natural and synthetic lactones containing an aromatic ring exhibit a number of biological properties, e.g. antiproliferative, antifeedant or antimicrobial activity. This review deals with the synthesis and biological properties of lactones containing an aromatic substituent in the β-position of the lactone ring. The described group of compounds includes halolactones, hydroxylactones, unsaturated lactones and products of reductive dehalogenation of iodolactones. In addition to chemical transformations, biotechnological methods for obtaining optically active lactones have also been described, in

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10

Tănase, Constantin, Lucia Pintilie, and Raluca Elena Tănase. "Lactones in the Synthesis of Prostaglandins and Prostaglandin Analogs." International Journal of Molecular Sciences 22, no. 4 (2021): 1572. http://dx.doi.org/10.3390/ijms22041572.

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In the total stereo-controlled synthesis of natural prostaglandins (PGs) and their structural analogs, a vast class of compounds and drugs, known as the lactones, are encountered in a few key steps to build the final molecule, as: δ-lactones, γ-lactones, and 1,9-, 1,11-, and 1,15-macrolactones. After the synthesis of 1,9-PGF2α and 1,15-PGF2α lactones, many 1,15-lactones of E2, E3, F2, F3, A2, and A3 were found in the marine mollusc Tethys fimbria and the quest for understanding their biological role stimulated the research on their synthesis. Then 1,9-, 1,11-, and 1,15-PG lactones of the drugs

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11

Elissalde, Marcel H., та G. Wayne Ivie. "Inhibition of macrophage adenylate cyclase by the α-methylene-γ-lactone moiety of sesquiterpene lactones from forage plants". American Journal of Veterinary Research 48, № 1 (1987): 148–52. https://doi.org/10.2460/ajvr.1987.48.01.148.

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SUMMARY Inhibition of murine macrophage adenylate cyclase activity by sesquiterpene lactones isolated from toxic forage plants was highly correlated with the presence of the α-methylene-γ-lactone moiety on the molecule (ie, hymenovin and helenalin). Tenulin, a sesquiterpene lactone which does not contain this reactive moiety, caused minimal inhibition of the enzyme. Reaction of the α-methylene-γ-lactone moiety of hymenovin and helenalin with cysteine decreased the number of reactive moieties available to alkylate the enzyme, thus decreasing the inhibition of adenylate cyclase by these 2 sesqui

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12

Gładkowski, Witold, Aleksandra Włoch, Aleksandra Pawlak та ін. "Preparation of Enantiomeric β-(2′,5′-Dimethylphenyl)Bromolactones, Their Antiproliferative Activity and Effect on Biological Membranes". Molecules 23, № 11 (2018): 3035. http://dx.doi.org/10.3390/molecules23113035.

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Three novel enantiomeric pairs of bromolactones possesing a 2,5-dimethylphenyl substituent at the β-position of the lactone ring have been synthesized from corresponding enantiomeric (E)-3-(2′,5′-dimethylphenyl)hex-4-enoic acids (4) by kinetically controlled bromolactonization with N-bromosuccinimide (NBS). γ-Bromo-δ-lactones (5) were isolated as the major products. Absolute configurations of stereogenic centers of γ-bromo-δ-lactones (5) were assigned based on X-ray analysis; configurations of cis δ-bromo-γ-lactones (6) and trans δ-bromo-γ-lactones (7) were determined based on mechanism of bro

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13

High, Ryan, Phil Bremer, Biniam Kebede, and Graham T. Eyres. "Comparison of Four Extraction Techniques for the Evaluation of Volatile Compounds in Spray-Dried New Zealand Sheep Milk." Molecules 24, no. 10 (2019): 1917. http://dx.doi.org/10.3390/molecules24101917.

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Recent growth and diversification of sheep milk products means more sophisticated methods are required to ensure their flavour quality. The objective of this study was to compare four extraction techniques for the analysis of volatile compounds in sheep milk by gas chromatography-mass spectrometry (GC-MS). Solvent Assisted Flavour Evaporation (SAFE), Solid Phase Microextraction (SPME), Headspace Sorptive Extraction (HSSE) and Stir Bar Sorptive Extraction (SBSE) were evaluated for their sensitivity, selectivity, reproducibility, and overall efficiency. A total of 48 volatile compounds from nine

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14

Błoszyk, E., and B. Drożdż. "Sesquiterpene lactones. Part XXII. Sesquiterpene lactones in Species of the Genus Chrysanthemum." Acta Societatis Botanicorum Poloniae 47, no. 1–2 (2015): 3–13. http://dx.doi.org/10.5586/asbp.1978.001.

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A method of effective study on sesquiterpeine lactones in unknown plant material was worked out. This method allows the choice of species with high sesquiterpene lactones content and interesting chemical composition. Studies were carried out on 14 species of <i>Chrysanthemum</i> s.l.. The method of elementary appreciation consisted in: estimation of the bitter principle index (assayed by the modified Ph-P.IV. method), quantitative analysis of lactone fractions and chromatographical examination. Quantitative analysis of sesquiterpene lactones in plant material was carried out by the

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15

Liu, Chen, Shao, et al. "AhlX, an N-acylhomoserine Lactonase with Unique Properties." Marine Drugs 17, no. 7 (2019): 387. http://dx.doi.org/10.3390/md17070387.

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N-Acylhomoserine lactonase degrades the lactone ring of N-acylhomoserine lactones (AHLs) and has been widely suggested as a promising candidate for use in bacterial disease control. While a number of AHL lactonases have been characterized, none of them has been developed as a commercially available enzymatic product for in vitro AHL quenching due to their low stability. In this study, a highly stable AHL lactonase (AhlX) was identified and isolated from the marine bacterium Salinicola salaria MCCC1A01339. AhlX is encoded by a 768-bp gene and has a predicted molecular mass of 29 kDa. The enzyme

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16

Gładkowski, Witold, Monika Siepka, Barbara Żarowska, et al. "Chalcone-Derived Lactones: Synthesis, Whole-Cell Biotransformation, and Evaluation of Their Antibacterial and Antifungal Activity." Molecules 28, no. 9 (2023): 3800. http://dx.doi.org/10.3390/molecules28093800.

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Four compounds with lactone moiety were synthesized from chalcone 1 in three- or four-step synthesis. γ-Bromo-δ-lactone 5 was the only product of bromolactonization of acid 4 whereas bromolactonization of ester 3, apart from lactone 5 also afforded its isomer 6 and two diastereoisomeric δ-hydroxy-γ-lactones 7 and 8. Lactone 8 was also obtained in 88% yield as a product of simultaneous dehalogenation and translactonization of γ-bromo-δ-lactone 5 by Penicillum frequentans AM 359. Chalcone-derived lactones 5–8 were subjected to the tests on antimicrobial activity and the results compared with act

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17

Porzio, Elena, Davide Andrenacci, and Giuseppe Manco. "Thermostable Lactonases Inhibit Pseudomonas aeruginosa Biofilm: Effect In Vitro and in Drosophila melanogaster Model of Chronic Infection." International Journal of Molecular Sciences 24, no. 23 (2023): 17028. http://dx.doi.org/10.3390/ijms242317028.

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Pseudomonas aeruginosa is one of the six antimicrobial-resistant pathogens known as “ESKAPE” that represent a global threat to human health and are considered priority targets for the development of novel antimicrobials and alternative therapeutics. The virulence of P. aeruginosa is regulated by a four-chemicals communication system termed quorum sensing (QS), and one main class of QS signals is termed acylhomoserine lactones (acyl-HSLs), which includes 3-Oxo-dodecanoil homoserine lactone (3-Oxo-C12-HSL), which regulates the expression of genes implicated in virulence and biofilm formation. La

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18

Gładkowski, Witold, Monika Siepka, Tomasz Janeczko та ін. "Synthesis and Antimicrobial Activity of Methoxy- Substituted γ-Oxa-ε-lactones Derived from Flavanones". Molecules 24, № 22 (2019): 4151. http://dx.doi.org/10.3390/molecules24224151.

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Six γ-oxa-ε-lactones, 4-phenyl-3,4-dihydro-2H-1,5-benzodioxepin-2-one (5a) and its five derivatives with methoxy groups in different positions of A and B rings (5b–f), were synthesized from corresponding flavanones. Three of the obtained lactones (5b,c,f) have not been previously described in the literature. Structures of all synthesized compounds were confirmed by complete spectroscopic analysis with the assignments of signals on 1H and 13C-NMR spectra to the corresponding atoms. In most cases, lactones 5a–f exerted an inhibitory effect on the growth of selected pathogenic bacteria (Escherich

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Dancewicz, Katarzyna, Barbara Ratuś, Filip Boratyński, Bożena Kordan, Beata Gabryś, and Czesław Wawrzeńczyk. "Effect of Oxygen Incorporation into Cyclohexanone Ring on Antifeedant Activity." Journal of Plant Protection Research 51, no. 1 (2011): 23–28. http://dx.doi.org/10.2478/v10045-011-0005-0.

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Effect of Oxygen Incorporation into Cyclohexanone Ring on Antifeedant ActivityThe behaviour of the peach potato aphidMyzus persicae(Sulz.) was studied during settling on plants. The experiment involved observing peach potato aphid activity after the application of some natural and synthetic cyclohexanones and the, respective ε-lactones and epoxy-ε-lactones which were obtained from the cyclohexanones. Stereochemistry, and the number and position of methyl substituents were important for the biological activity of the starting compounds: only trimethyl-substituted cyclohexanones were active,i.e.

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20

Borchardt, S. A., E. J. Allain, J. J. Michels, G. W. Stearns, R. F. Kelly, and W. F. McCoy. "Reaction of Acylated Homoserine Lactone Bacterial Signaling Molecules with Oxidized Halogen Antimicrobials." Applied and Environmental Microbiology 67, no. 7 (2001): 3174–79. http://dx.doi.org/10.1128/aem.67.7.3174-3179.2001.

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ABSTRACT Oxidized halogen antimicrobials, such as hypochlorous and hypobromous acids, have been used extensively for microbial control in industrial systems. Recent discoveries have shown that acylated homoserine lactone cell-to-cell signaling molecules are important for biofilm formation in Pseudomonas aeruginosa, suggesting that biofouling can be controlled by interfering with bacterial cell-to-cell communication. This study was conducted to investigate the potential for oxidized halogens to react with acylated homoserine lactone-based signaling molecules. Acylated homoserine lactones contai

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Semakov, A. V., L. V. Anikina, and S. G. Klochkov. "Synthesis and Cytotoxic Activity of the Products of Addition of Thiophenol to Sesquiterpene Lactones." Russian Journal of Bioorganic Chemistry 47, no. 4 (2021): 906–17. http://dx.doi.org/10.1134/s106816202104018x.

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Abstract— Derivatives of sesquiterpene lactones modified at the lactone ring with a thiophenol residue have been synthesized. The resulting conjugates with thiophenol have capacity for the oxidation–elimination reaction by the action of ROS of a tumor cell with the release of initial cytotoxic lactones. It has been proposed to use the resulting sulfur-containing conjugates as ROS-activated prodrugs of sesquiterpene lactones. The antiproliferative properties of the conjugates have been examined on tumor and pseudonormal cell lines. The cytotoxicity of the conjugates is lower than that of parent

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Lutter, E., S. Lewenza, J. J. Dennis, M. B. Visser, and P. A. Sokol. "Distribution of Quorum-Sensing Genes in the Burkholderia cepacia Complex." Infection and Immunity 69, no. 7 (2001): 4661–66. http://dx.doi.org/10.1128/iai.69.7.4661-4666.2001.

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ABSTRACT The distribution of quorum-sensing genes among strains from seven genomovars of the Burkholderia cepaciacomplex was examined by PCR. cepR and cepI were amplified from B. cepacia genomovars I and III, B. stabilis, and B. vietnamiensis. cepR was also amplified from B. multivorans and B. cepacia genomovar VI. bviIR were amplified from B. vietnamiensis. All genomovars producedN-octanoyl-l-homoserine lactone andN-hexanoyl-l-homoserine lactone.B. vietnamiensis and B. cepacia genomovar VII produced additional N-acyl-l-homoserine lactones.

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23

Włoch, Aleksandra, Dominika Stygar, Fouad Bahri та ін. "Antiproliferative, Antimicrobial and Antiviral Activity of β-Aryl-δ-iodo-γ-lactones, Their Effect on Cellular Oxidative Stress Markers and Biological Membranes". Biomolecules 10, № 12 (2020): 1594. http://dx.doi.org/10.3390/biom10121594.

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The aim of this work was the examination of biological activity of three selected racemic cis-β-aryl-δ-iodo-γ-lactones. Tested iodolactones differed in the structure of the aromatic fragment of molecule, bearing isopropyl (1), methyl (2), or no substituent (3) on the para position of the benzene ring. A broad spectrum of biological activity as antimicrobial, antiviral, antitumor, cytotoxic, antioxidant, and hemolytic activity was examined. All iodolactones showed bactericidal activity against Proteus mirabilis, and lactones 1,2 were active against Bacillus cereus. The highest cytotoxic activit

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Majerczyk, Charlotte, Loren Kinman, Tony Han, Richard Bunt, and E. Peter Greenberg. "Virulence of Burkholderia mallei Quorum-Sensing Mutants." Infection and Immunity 81, no. 5 (2013): 1471–78. http://dx.doi.org/10.1128/iai.00048-13.

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ABSTRACTManyProteobacteriause acyl-homoserine lactone-mediated quorum-sensing (QS) to activate specific sets of genes as a function of cell density. QS often controls the virulence of pathogenic species, and in fact a previous study indicated that QS was important forBurkholderia malleimouse lung infections. To gain in-depth information on the role of QS inB. malleivirulence, we constructed and characterized a mutant ofB. malleistrain GB8 that was unable to make acyl-homoserine lactones. The QS mutant showed virulence equal to that of its wild-type parent in an aerosol mouse infection model, a

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Hakobyan, Robert M., Levon A. Kharatyan, Sargis S. Hayotsyan, Hovhannes S. Attaryan та Gagik S. Melikyan. "SYNTHESIS OF NEW γ-LACTONE RING DERIVATIVES CONTAINING PYRIDINE AND TRICONDENSED SYSTEMS". ChemChemTech 67, № 7 (2024): 28–40. http://dx.doi.org/10.6060/ivkkt.20246707.7068.

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Lactone-pyridone rings contain many biologically active molecules of natural and artificial origin. The molecules contained in these two rings, represented by Cerpegine and its derivatives, will also exhibit high biological activity. It is also necessary to take into account that both natural and synthetic multi-substituted lactones have high biological activity. Thus, research in the field of multi-substituted lactones and further transformations are of particular interest. The synthesis of such systems began with the synthesis of a 2-acetylfuranone ring. In the next step, condensation of eth

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Aertker, Kristina M. J., H. T. Henry Chan, Christopher T. Lohans та Christopher J. Schofield. "Analysis of β-lactone formation by clinically observed carbapenemases informs on a novel antibiotic resistance mechanism". Journal of Biological Chemistry 295, № 49 (2020): 16604–13. http://dx.doi.org/10.1074/jbc.ra120.014607.

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An important mechanism of resistance to β-lactam antibiotics is via their β-lactamase–catalyzed hydrolysis. Recent work has shown that, in addition to the established hydrolysis products, the reaction of the class D nucleophilic serine β-lactamases (SBLs) with carbapenems also produces β-lactones. We report studies on the factors determining β-lactone formation by class D SBLs. We show that variations in hydrophobic residues at the active site of class D SBLs (i.e. Trp105, Val120, and Leu158, using OXA-48 numbering) impact on the relative levels of β-lactones and hydrolysis products formed. So

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Barbosa, Luiz Claúdio de A., Adilson V. Costa, Dorila Piló-Veloso, et al. "Phytogrowth-Inhibitory Lactones Derivatives of Glaucolide B." Zeitschrift für Naturforschung C 59, no. 11-12 (2004): 803–10. http://dx.doi.org/10.1515/znc-2004-11-1207.

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The sesquiterpene lactone glaucolide B (1), isolated from Vernonia fruticulosa (Asteraceae), was transformed into six lactones (2-7). The structures of the products were elucidated by spectroscopic analysis. A series of solutions of compounds 1-7, at 200 μᴍ, were tested on the germination and on the root and shoot growth of the dicotyledons Physalis ixocarpa and Trifolium alexandrinum and of the monocotyledons Lolium multiflorum and Amaranthus hypochondriacus. Lactone 5 exhibited clear selectivity towards dicotyledonous species at 200 μᴍ, with an average inhibition of 90% on the germination of

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Chany, Anne-Caroline, Léo B. Marx, and Jonathan W. Burton. "Synthesis of bicyclic tetrahydrofurans from linear precursors using manganese(iii) acetate." Organic & Biomolecular Chemistry 13, no. 35 (2015): 9190–93. http://dx.doi.org/10.1039/c5ob01091h.

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Cyclisation of a range of alkoxy-malonates in the presence of manganese(iii) acetate gives rise to bicyclic lactone/THFs and lactone/lactones in synthetically useful yields and diastereoselectivities.

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Bińczak, Jakub, Krzysztof Dziuba, and Anna Chrobok. "Recent Developments in Lactone Monomers and Polymer Synthesis and Application." Materials 14, no. 11 (2021): 2881. http://dx.doi.org/10.3390/ma14112881.

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Lactones are a group of compounds that have been known for several decades. The commercial importance of lactones results from the possibility of manufacturing of a broad scope of derivatives and polymers with a wide spectrum of applications. In this work the synthesis and characterization of simple lactones are described, which due to the easy methods of the synthesis are of high importance for the industry. The chemical as well as biochemical methods are included with special attention paid to the methods that avoid metal catalysts, initiators or toxic solvents, allowing the use of the final

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30

Błoszyk, Ełżbieta, Aleksandra Dudek, Zofia Kosturkiewicz, et al. "Sesquiterpene lactones of Cephalophora aromatica (HOOK.) SCHRADER and their deterrent activity. The stereostructure of geigerinin." Collection of Czechoslovak Chemical Communications 54, no. 7 (1989): 1903–18. http://dx.doi.org/10.1135/cccc19891903.

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From species Cephalophora aromatica (HOOK.) SCHRADER the authors isolated a series of previously described sesquiterpene lactones I-V and newly the lactone geigerinin (VI). Its structure was confirmed by X-ray analysis and its absolute configuration was determined on the basis of the CD spectra of its complex with Pr(thd)3. The lactones I-VII were tested for antifeedant activity against main crop pests.

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Mandal, Sudip Kumar, Utsab Debnath, Amresh Kumar, et al. "Natural Sesquiterpene Lactones in the Prevention and Treatment of Inflammatory Disorders and cancer: A Systematic Study of this Emerging Therapeutic Approach based on Chemical and Pharmacological Aspect." Letters in Drug Design & Discovery 17, no. 9 (2020): 1102–16. http://dx.doi.org/10.2174/1570180817999200421144007.

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Background and Introduction: Sesquiterpene lactones are a class of secondary metabolite that contains sesquiterpenoids and lactone ring as pharmacophore moiety. A large group of bioactive secondary metabolites such as phytopharmaceuticals belong to this category. From the Asteraceae family-based medicinal plants, more than 5,000 sesquiterpene lactones have been reported so far. Sesquiterpene lactone-based pharmacophore moieties hold promise for broad-spectrum biological activities against cancer, inflammation, parasitic, bacterial, fungal, viral infection and other functional disorders. Moreov

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Kim, Younghoon, Sandip Sengupta, and Taebo Sim. "Natural and Synthetic Lactones Possessing Antitumor Activities." International Journal of Molecular Sciences 22, no. 3 (2021): 1052. http://dx.doi.org/10.3390/ijms22031052.

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Cancer is one of the leading causes of death globally, accounting for an estimated 8 million deaths each year. As a result, there have been urgent unmet medical needs to discover novel oncology drugs. Natural and synthetic lactones have a broad spectrum of biological uses including anti-tumor, anti-helminthic, anti-microbial, and anti-inflammatory activities. Particularly, several natural and synthetic lactones have emerged as anti-cancer agents over the past decades. In this review, we address natural and synthetic lactones focusing on their anti-tumor activities and synthetic routes. Moreove

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Mazur, Marcelina, and Dorota Masłowiec. "Antimicrobial Activity of Lactones." Antibiotics 11, no. 10 (2022): 1327. http://dx.doi.org/10.3390/antibiotics11101327.

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The development of bacterial resistance to antibiotics and the consequent lack of effective therapy is one of the biggest problems in modern medicine. A consequence of these processes is an urgent need to continuously design and develop novel antimicrobial agents. Among the compounds showing antimicrobial potential, lactones are a group to explore. For centuries, their antimicrobial activities have been used in folk medicine. Currently, novel lactone compounds are continuously described in the literature. Some of those structures exhibit high antimicrobial potential and some are an inspiration

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Tang, Kaihao, Ying Su, Gilles Brackman, et al. "MomL, a Novel Marine-DerivedN-Acyl Homoserine Lactonase from Muricauda olearia." Applied and Environmental Microbiology 81, no. 2 (2014): 774–82. http://dx.doi.org/10.1128/aem.02805-14.

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ABSTRACTGram-negative bacteria useN-acyl homoserine lactones (AHLs) as quorum sensing (QS) signaling molecules for interspecies communication, and AHL-dependent QS is related with virulence factor production in many bacterial pathogens. Quorum quenching, the enzymatic degradation of the signaling molecule, would attenuate virulence rather than kill the pathogens, and thereby reduce the potential for evolution of drug resistance. In a previous study, we showed thatMuricauda oleariaTh120, belonging to the classFlavobacteriia, has strong AHL degradative activity. In this study, an AHL lactonase (

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Pawlak, Aleksandra, Marta Henklewska, Beatriz Hernández-Suárez та ін. "Methoxy-Substituted γ-Oxa-ε-Lactones Derived from Flavanones—Comparison of Their Anti-Tumor Activity In Vitro". Molecules 26, № 20 (2021): 6295. http://dx.doi.org/10.3390/molecules26206295.

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Background: The study investigated four flavanone-derived γ-oxa-ε-lactones: a parent unsubstituted compound and its three derivatives with the methoxy group in positions 2′, 4′ and 8. Our objective was to find out if the introduction of the methoxy group into the aromatic ring affects in vitro anti-tumor potency of the investigated lactones. Methods: Cytotoxic and pro-apoptotic effects were assessed with cytometric tests with propidium iodide, annexin V, and Western blot techniques. We also investigated potential synergistic potency of the tested lactones and glucocorticoids in canine lymphoma

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Silva, Rui, Eduardo Coelho, Tatiana Q. Aguiar, and Lucília Domingues. "Microbial Biosynthesis of Lactones: Gaps and Opportunities towards Sustainable Production." Applied Sciences 11, no. 18 (2021): 8500. http://dx.doi.org/10.3390/app11188500.

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Lactones are volatile organic compounds widely present in foods. These chemicals are applied as flavors and fragrances in the food, cosmetics and pharmaceutical industries. Recently, the potential of lactones as green solvents and fuel precursors reinforced their role as platform compounds of future bio-based economies. However, their current mode of production needs to change. Lactones are mainly obtained through chemical synthesis or microbial biotransformation of hydroxy fatty acids. The latter approach is preferred but still needs to use more sustainable substrates. Hydroxy fatty acids are

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Mukhidova, Zulfiya Sh, Salakhutdin H. Zakirov, Sevara M. Khazratkulova, and Nodira T. Zakirova. "Prospects for the use of natural terpenoids in agriculture." BIO Web of Conferences 82 (2024): 03001. http://dx.doi.org/10.1051/bioconf/20248203001.

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As a result of the conducted phytochemical studies of sesquiterpene lactones of some plants of the genus Artemisia, Centaurea, Jurinea, and Handelia of the Asteraceae family and the study of biostimulating, mutagenic, and insecticidal activity of isolated individual lactones and total preparations in rice farming, cotton growing, as well as against termites, the following biologically active environmentally safe natural remedies have been created: an effective stimulant that, when soaking rice seeds, increases the yield 12-14 quintals per hectare as an average, promising mutant lines and two n

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Husinec, Suren, and Vladimir Savic. "The synthesis of some unsaturated 4-substituted-g-lactones." Journal of the Serbian Chemical Society 65, no. 2 (2000): 87–93. http://dx.doi.org/10.2298/jsc0002087h.

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The synthesis of conjugated and nonconjugated unsaturated 4-substituted lactones of type 1 and 2 are described. The type 1 lactone was prepared by a two step procedure employing Bredereck's reagent. The type 2 lactone was synthesised by combining the Claisen-Ireland rearrangement and selenolactonisation.

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Chan, Ying Ying, Hao Sheng Bian, Theresa May Chin Tan, et al. "Control of Quorum Sensing by a Burkholderia pseudomallei Multidrug Efflux Pump." Journal of Bacteriology 189, no. 11 (2007): 4320–24. http://dx.doi.org/10.1128/jb.00003-07.

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ABSTRACT The Burkholderia pseudomallei KHW quorum-sensing systems produced N-octanoyl-homoserine lactone, N-decanoyl-homoserine lactone, N-(3-hydroxy)-octanoyl-homoserine lactone, N-(3-hydroxy)-decanoyl-homoserine lactone, N-(3-oxo)-decanoyl-homoserine lactone, and N-(3-oxo)-tetradecanoyl-homoserine lactone. The extracellular secretion of these acyl-homoserine lactones is dependent absolutely on the function of the B. pseudomallei BpeAB-OprB efflux pump.

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Deslongchamps, Pierre, Daniel Guay, and Robert Chènevert. "The hydrolysis of cis and trans methoxy bicyclic and tricyclic orthoesters. Evidence for a chair–boat inversion prior to breakdown in some hemiorthoester tetrahedral intermediates." Canadian Journal of Chemistry 63, no. 9 (1985): 2493–500. http://dx.doi.org/10.1139/v85-413.

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The acid hydrolysis of cis and trans methoxy bicyclic and tricyclic orthoesters 1–4 was studied. The trans isomers gave only the corresponding hydroxy-lactones (2 → 14 and 4 → 16 + 10) whereas the cis isomers gave mixtures of dihydroxy-esters and hydroxy-lactones (1 → 13 + 14) and 3 → 15 + 16 + 10). These results are rationalized on the basis of the stereoelectronic theory for hydrolytic processes. The fact that hydroxy-lactone 16 is produced to a larger extent than the isomeric hydroxy-lactone 10 is taken as evidence that when a tetrahedral intermediate is not allowed (stereoelectronically) t

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Paço, Ana, Teresa Brás, Jacqueline O. Santos, Paula Sampaio, Andreia C. Gomes, and Maria F. Duarte. "Anti-Inflammatory and Immunoregulatory Action of Sesquiterpene Lactones." Molecules 27, no. 3 (2022): 1142. http://dx.doi.org/10.3390/molecules27031142.

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Sesquiterpene lactones (SL), characterized by their high prevalence in the Asteraceae family, are one of the major groups of secondary metabolites found in plants. Researchers from distinct research fields, including pharmacology, medicine, and agriculture, are interested in their biological potential. With new SL discovered in the last years, new biological activities have been tested, different action mechanisms (synergistic and/or antagonistic effects), as well as molecular structure–activity relationships described. The review identifies the main sesquiterpene lactones with interconnection

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Liu, Ling-Pu, Long-Hui Huang, Xiao-Tong Ding, et al. "Identification of Quorum-Sensing Molecules of N-Acyl-Homoserine Lactone in Gluconacetobacter Strains by Liquid Chromatography-Tandem Mass Spectrometry." Molecules 24, no. 15 (2019): 2694. http://dx.doi.org/10.3390/molecules24152694.

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Many Gram-negative bacteria can regulate gene expression in a cell density-dependent manner via quorum-sensing systems using N-acyl-homoserine lactones (AHLs), which are typical quorum-sensing signaling molecules, and thus modulate physiological characteristics. N-acyl-homoserine lactones are small chemical molecules produced at low concentrations by bacteria and are, therefore, difficult to detect. Here, a biosensor system method and liquid chromatography-tandem mass spectrometry were combined to detect and assay AHL production. As demonstrated by liquid chromatography-tandem mass spectrometr

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Lynch, MJ, J. Simpson, and RT Weavers. "Diiodo Acetals and Unsaturated Lactones From Dihydropyran." Australian Journal of Chemistry 46, no. 2 (1993): 203. http://dx.doi.org/10.1071/ch9930203.

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Reaction of dihydropyran with propiolic acid and N- iodosuccinimide gave an iodo ester which was cyclized under free-radical conditions to form an (E) iodomethylene lactone. Photolysis of this lactone could be controlled to generate mixtures of (E) and (Z) iodomethylene lactones, or alternatively the iodine-free methylene lactone. The structures of some by-products of the iodo ester formation have been shown to be a succinimide derivative and two stereoisomers of a diiodo acetal. X-Ray determination of the structure of one of the diiodo acetal isomers is described.

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NANTASENAMAT, CHANIN, THEERAPHON PIACHAM, TANAWUT TANTIMONGCOLWAT, THANAKORN NAENNA, CHARTCHALERM ISARANKURA-NA-AYUDHYA, and VIRAPONG PRACHAYASITTIKUL. "QSAR MODEL OF THE QUORUM-QUENCHING N-ACYL-HOMOSERINE LACTONE LACTONASE ACTIVITY." Journal of Biological Systems 16, no. 02 (2008): 279–93. http://dx.doi.org/10.1142/s021833900800254x.

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A quantitative structure-activity relationship (QSAR) study was performed to model the lactonolysis activity of N-acyl-homoserine lactone lactonase. A data set comprising of 20 homoserine lactones and related compounds was taken from the work of Wang et al. Quantum chemical descriptors were calculated using the semiempirical AM1 method. Partial least squares regression was utilized to construct a predictive model. This computational approach reliably reproduced the lactonolysis activity with high accuracy as illustrated by the correlation coefficient in excess of 0.9. It is demonstrated that t

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Adekenov, S. M., and G. A. Atazhanova. "Heteroatom-Containing Natural Sesquiterpene Lactones and Methods for their Obtaining." Eurasian Chemico-Technological Journal 15, no. 3 (2013): 195. http://dx.doi.org/10.18321/ectj223.

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This review shows the data about isolated heteroatom-containing sesquiterpene lactones from various genera of <em>Asteraceae</em> family, natural occurence, isolation methods and their biological activity. Chlorinecontaining sesquiterpene lactones were isolated from genera of<em> Artemisia</em> L., <em>Achillea</em> L., <em>Acroptilon Cass</em>, <em>Centaurea</em> L., <em>Chartolepis Cass</em>, <em>Eupatorium</em> L., <em>Jurinea Cass</em>, <em>Rhaponticum Adams</em>, <em>Saussurea

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Merbouh, Nabyl, Simon Cassegrain, and Wen Zhou. "4-Phenylnaphtho[2,3-c]furan-1(3H)-one, 9-Phenylnaphtho[2,3-c]furan-1(3H)-one and 3a,4-Dihydro-9-phenylnaphtho[2,3-c]furan-1(3H)-one Crystal Structures." Crystals 11, no. 8 (2021): 857. http://dx.doi.org/10.3390/cryst11080857.

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The crystal structures are reported for two unsubstituted arylnaphthalene lactones, 4-phenylnaphtho[2,3-c]furan-1(3H)-one (2), 9-phenylnaphtho[2,3-c]furan-1(3H)-one (3) and a non-aromatic dihydro arylnaphthene lactone, 3a,4-dihydro-9-phenylnaphtho[2,3-c]furan-1(3H)-one (5). There are only minor differences in the geometrical parameters of these structures. However, in certain cases, both isomers of arylnaphthalene lactones (termed Type I and Type II) were found in the same asymmetric unit cell.

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Grant, PK, LR Hanton, GP Lynch, J. Simpson, and GC Slim. "Assignment of Local Conformation in Medium-Ring Unsaturated Lactones Derived From Labda-8(17),14-dien-13-Ol (Manool)." Australian Journal of Chemistry 44, no. 7 (1991): 897. http://dx.doi.org/10.1071/ch9910897.

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The unsaturated lactone (2) derived from manool (1) has a particularly rigid 10-membered ring which gives rise to high asymmetric induction in epoxidation with m-chloroperoxybenzoic acid. The corresponding 11-membered lactone (14) shows greater flexibility. The conformations of lactone (2) and epoxy lactones (12) and (13) have been determined by X-ray diffraction studies.

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Ng, Filomena S. W., Daniel M. Wright, and Stephen Y. K. Seah. "Characterization of a Phosphotriesterase-Like Lactonase fromSulfolobus solfataricusand Its Immobilization for Disruption of Quorum Sensing." Applied and Environmental Microbiology 77, no. 4 (2010): 1181–86. http://dx.doi.org/10.1128/aem.01642-10.

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ABSTRACTSsoPox, a bifunctional enzyme with organophosphate hydrolase andN-acyl homoserine lactonase activities from the hyperthermophilic archaeonSulfolobus solfataricus, was overexpressed and purified from recombinantPseudomonas putidaKT2440 with a yield of 9.4 mg of protein per liter of culture. The enzyme has a preference forN-acyl homoserine lactones (AHLs) with acyl chain lengths of at least 8 carbon atoms, mainly due to lowerKmvalues for these substrates. The highest specificity constant obtained was forN-3-oxo-decanoyl homoserine lactone (kcat/Km= 5.5 × 103M−1·s−1), but SsoPox can also

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Verdaguer, Xavier, Marcus C. Hansen, Scott C. Berk, and Stephen L. Buchwald. "Titanocene-Catalyzed Reduction of Lactones to Lactols." Journal of Organic Chemistry 62, no. 24 (1997): 8522–28. http://dx.doi.org/10.1021/jo971560s.

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Clauser, Maria, Nicola Aiello, Fabrizio Scartezzini, Gabbriella Innocenti, and Stefano Dall'Acqua. "Differences in the Chemical Composition of Arnica montana Flowers from Wild Populations of North Italy." Natural Product Communications 9, no. 1 (2014): 1934578X1400900. http://dx.doi.org/10.1177/1934578x1400900102.

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The flower heads of fourteen wild Arnica montana L. populations were collected in the summer of 2010 in the provinces of Trento, Brescia and Bergamo (Italy). The dried flowers were analyzed to assess their chemical diversity. HLPC-MS analysis led to the identification of phenolic derivatives and sesquiterpene lactones in the samples, confirming literature data. Quali-quantitative analysis of the flower heads showed similar qualitative patterns both for the phenolic as well as sesquiterpene lactone derivatives, while significant variability was obtained in the amounts (HPLC-DAD) of sesquiterpen

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