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Journal articles on the topic 'Polyenen'

Author: Grafiati

Published: 4 June 2021

Last updated: 28 July 2025

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1

Otto, André. "Kekule-Strukturen in Di-Polyenen." Zeitschrift für Chemie 27, no. 9 (2010): 342–43. http://dx.doi.org/10.1002/zfch.19870270917.

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2

Loeschcke, I., J. Friedrich, and P. Lutgen. "XPS-Untersuchungen von im H2-Plasma erzeugten Polyenen in PVC." Acta Polymerica 41, no. 10 (1990): 553–54. http://dx.doi.org/10.1002/actp.1990.010411011.

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3

Rao, T. Venu Gopala, Akhilesh Trivedi, and Rajendra Prasad. "Phospholipid enrichment of Saccharomyces cerevisiae and its effect on polyene sensitivity." Canadian Journal of Microbiology 31, no. 4 (1985): 322–26. http://dx.doi.org/10.1139/m85-061.

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Sensitivity to polyene antibiotics, e.g., nystatin, amphotericin B, and filipin, was determined in phosphatidylcholine (PC) or phosphatidylethanolamine (PE) or phosphatidylserine (PS) enriched Saccharomyces cerevisiae cells, using glutamic acid, phenylalanine, glycine, and lysine transport as an index of polyene antibiotic action. As compared with normal cells, phospholipid-enriched cells acquired resistance towards different polyenes. However, the sensitivity of glutamic acid transport towards nystatin remained unaffected in PC-, PE-, or PS-enriched cells. In contrast to nystatin, the other t

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4

Carolus, Hans, Siebe Pierson, Katrien Lagrou, and Patrick Van Dijck. "Amphotericin B and Other Polyenes—Discovery, Clinical Use, Mode of Action and Drug Resistance." Journal of Fungi 6, no. 4 (2020): 321. http://dx.doi.org/10.3390/jof6040321.

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Although polyenes were the first broad spectrum antifungal drugs on the market, after 70 years they are still the gold standard to treat a variety of fungal infections. Polyenes such as amphotericin B have a controversial image. They are the antifungal drug class with the broadest spectrum, resistance development is still relatively rare and fungicidal properties are extensive. Yet, they come with a significant host toxicity that limits their use. Relatively recently, the mode of action of polyenes has been revised, new mechanisms of drug resistance were discovered and emergent polyene resista

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5

BOGENSCHÜTZ, H., W. KNAUF, E. J. TRÖGER, H. J. BESTMANN, and O. VOSTROWSKY. "Pheromone 491: Freilandfänge von Geometriden-Männchen mit C19-Polyenen in Kiefernbeständen." Zeitschrift für Angewandte Entomologie 100, no. 1-5 (2009): 349–54. http://dx.doi.org/10.1111/j.1439-0418.1985.tb02790.x.

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6

Pekmezovic, Marina, Melina Kalagasidis Krusic, Ivana Malagurski, et al. "Polyhydroxyalkanoate/Antifungal Polyene Formulations with Monomeric Hydroxyalkanoic Acids for Improved Antifungal Efficiency." Antibiotics 10, no. 6 (2021): 737. http://dx.doi.org/10.3390/antibiotics10060737.

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Novel biodegradable and biocompatible formulations of “old” but “gold” drugs such as nystatin (Nys) and amphotericin B (AmB) were made using a biopolymer as a matrix. Medium chain length polyhydroxyalkanoates (mcl-PHA) were used to formulate both polyenes (Nys and AmB) in the form of films (~50 µm). Thermal properties and stability of the materials were not significantly altered by the incorporation of polyenes in mcl-PHA, but polyene containing materials were more hydrophobic. These formulations were tested in vitro against a panel of pathogenic fungi and for antibiofilm properties. The films

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7

Šebelík, Václav, Miroslav Kloz, Mateusz Rebarz, et al. "Spectroscopy and excited state dynamics of nearly infinite polyenes." Physical Chemistry Chemical Physics 22, no. 32 (2020): 17867–79. http://dx.doi.org/10.1039/d0cp02465a.

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8

Ngece, Kwanele, Thabisa L. Ntondini, Vuyolwethu Khwaza, Athandwe M. Paca, and Blessing A. Aderibigbe. "Polyene-Based Derivatives with Antifungal Activities." Pharmaceutics 16, no. 8 (2024): 1065. http://dx.doi.org/10.3390/pharmaceutics16081065.

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Polyenes are a class of organic compounds well known for their potent antifungal properties. They are effective due to their ability to target and disrupt fungal cell membranes by binding to ergosterol and forming pores. Despite their effectiveness as antifungal drugs, polyenes have several limitations, such as high toxicity to the host cell and poor solubility in water. This has prompted ongoing research to develop safer and more efficient derivatives to overcome such limitations while enhancing their antifungal activity. In this review article, we present a thorough analysis of polyene deriv

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9

Langler, Richard F. "Monocyclic Electrocyclic Transition States are Neither Favoured Nor Disfavoured if the Incipient Ring Bears More Than Two Odd Substituents." Australian Journal of Chemistry 63, no. 9 (2010): 1402. http://dx.doi.org/10.1071/ch10165.

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A general case is presented that supports the conclusion that incipient π-bond orders, op1,j, are approximately zero if the incipient alternant ring bears more than two odd substituents. Hence, corresponding electrocyclic transition states are neither favoured nor disfavoured. The case is made using permethylene polyenes. After presentation of the novel application of dense Sachs’ subgraphs to the problem of convenient, rapid access to permethylene polyene characteristic polynomials, permethylene polyenes are shown to belong to the newly defined Hückel symmetrenes. Employing novel expressions

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10

Baghirova, A. A., and Kh M. Kasumov. "Antifungal macrocycle antibiotic amphotericin B — its present and future. Multidisciplinary perspective for the use in the medical practice." Biomeditsinskaya Khimiya 67, no. 4 (2021): 311–22. http://dx.doi.org/10.18097/pbmc20216704311.

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This review is devoted to a broad analysis of the results of studies of the effect of macrocyclic antifungal polyene antibiotic amphotericin B on cell membranes. A multi-prolonged study of polyenes showed that some of them can have not only antifungal, but also antiviral and antitumor action. Fungal pathology develops especially quickly and in this case leads to invasive aspergillosis, which contributes to the complication of coronavirus infection in the lungs and even secondary infection with invasive aspergillosis in the context of a global pandemic. The treatment of an invasive form of bron

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11

Oloba-Whenu, Oluwakemi A., Thomas A. Albright, and Chirine Soubra-Ghaoui. "Ring-whizzing in polyene-PtL2 complexes revisited." Beilstein Journal of Organic Chemistry 12 (July 7, 2016): 1410–20. http://dx.doi.org/10.3762/bjoc.12.135.

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Ring-whizzing was investigated by hybrid DFT methods in a number of polyene–Pt(diphosphinylethane) complexes. The polyenes included cyclopropenium+, cyclobutadiene, cyclopentadienyl+, hexafluorobenzene, cycloheptatrienyl+, cyclooctatetraene, octafluorooctatetraene, 6-radialene, pentalene, phenalenium+, naphthalene and octafluoronaphthalene. The HOMO of a d10 ML2 group (with b2 symmetry) interacting with the LUMO of the polyene was used as a model to explain the occurrence of minima and maxima on the potential energy surface.

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12

Malysheva, L. I. "Analytic Analysis of Electronic and Transport Properties of Finite Polyenes." Ukrainian Journal of Physics 66, no. 7 (2021): 619. http://dx.doi.org/10.15407/ujpe66.7.619.

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Various important characteristics of finite polyene chains are found on the basis of approximate solutions of the characteristic equations. The obtained approximate and limit expressions for the wave functions, energy gap, etc. can be used for the analysis of the electronic and transport properties of polyenes, which gives a deeper understanding of the fundamental properties of finite alternating polyene chains. We also demonstrate the high efficiency of the proposed approximations as a zero-order estimate for the numerical solution of the characteristic equation.

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13

Palacios, Rodrigo E., Stephanie L. Gould, Christian Herrero, et al. "Bioinspired energy conversion." Pure and Applied Chemistry 77, no. 6 (2005): 1001–8. http://dx.doi.org/10.1351/pac200577061001.

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Artificial photosynthetic antenna systems have been synthesized based on carotenoid polyenes and polymer-polyenes covalently attached to tetrapyrroles. Absorption of light in the blue/green region of the spectra excites the polyenes to their S2 state, and ultrafast singlet energy transfer to the tetrapyrroles occurs when the chromophores are in partial conjugation. The additional participation of other excited states of the polyene in the energy-transfer process is a requirement for perfect antenna function. Analogs of photosynthetic reaction centers consisting of tetrapyrrole chromophores cov

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14

Haro-Reyes, Tammy, Lucero Díaz-Peralta, Arturo Galván-Hernández, Anahi Rodríguez-López, Lourdes Rodríguez-Fragoso, and Iván Ortega-Blake. "Polyene Antibiotics Physical Chemistry and Their Effect on Lipid Membranes; Impacting Biological Processes and Medical Applications." Membranes 12, no. 7 (2022): 681. http://dx.doi.org/10.3390/membranes12070681.

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This review examined a collection of studies regarding the molecular properties of some polyene antibiotic molecules as well as their properties in solution and in particular environmental conditions. We also looked into the proposed mechanism of action of polyenes, where membrane properties play a crucial role. Given the interest in polyene antibiotics as therapeutic agents, we looked into alternative ways of reducing their collateral toxicity, including semi-synthesis of derivatives and new formulations. We follow with studies on the role of membrane structure and, finally, recent developmen

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15

Petersen, Nils O. "Intramolecular fluorescence energy transfer in nitrobenzoxadiazole derivatives of polyene antibiotics." Canadian Journal of Chemistry 63, no. 1 (1985): 77–85. http://dx.doi.org/10.1139/v85-014.

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Spectroscopic properties of the polyene antibiotic Nystatin and its nitrobenzoxadiazole derivative have been characterized by lifetime and quantum yield measurements. The data suggest that Nystatin and other polyene antibiotics exhibit spectral features common to other linear polyenes such as diphenylhexatriene and parinaric acid, and support the conclusion that the strong absorption (εmax ~70 000 M−1 cm−1; λ = 306 nm) is due to a symmetry-allowed transition to a higher excited state while the red-shifted emission occurs from a lower lying excited state through a weak, symmetry-forbidden trans

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16

Efimova, S. S., L. V. Schagina, and O. S. Ostroumova. "Investigation of Channel-Forming Activity of Polyene Macrolide Antibiotics in Planar Lipid Bilayers in the Presence of Dipole Modifiers." Acta Naturae 6, no. 4 (2014): 67–79. http://dx.doi.org/10.32607/20758251-2014-6-4-67-79.

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The role of membrane components, sterols, phospholipids and sphingolipids in the formation and functioning of ion-permeable nanopores formed by antifungal macrolide antibiotics, amphotericin B, nystatin and filipin in planar lipid bilayers was studied. Dipole modifiers, flavonoids and styryl dyes, were used as a tool to study the molecular mechanisms of polyene channel-forming activity. The introduction of dipole modifiers into the membrane bathing solutions was shown to change the conductance of single channels and the steadystate transmembrane current induced by polyene antibiotics in the st

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17

Caffrey, Patrick, Mark Hogan, and Yuhao Song. "New Glycosylated Polyene Macrolides: Refining the Ore from Genome Mining." Antibiotics 11, no. 3 (2022): 334. http://dx.doi.org/10.3390/antibiotics11030334.

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Glycosylated polyene macrolides include effective antifungal agents, such as pimaricin, nystatin, candicidin, and amphotericin B. For the treatment of systemic mycoses, amphotericin B has been described as a gold-standard antibiotic because of its potent activity against a broad spectrum of fungal pathogens, which do not readily become resistant. However, amphotericin B has severe toxic side effects, and the development of safer alternatives remains an important objective. One approach towards obtaining such compounds is to discover new related natural products. Advances in next-generation seq

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18

Stolarczyk, Leszek, Tadeusz Krygowski, and Michał Cyrański. "NAPRĘŻENIE KĄTOWE W MOLEKULE BENZENU?" Wiadomości Chemiczne 78, no. 7 (2024): 973–86. https://doi.org/10.53584/wiadchem.2024.07.9.

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The stabilization energies (often called the aromatic stabilization energies) of π-electron molecules play important role in discussing the properties of these systems. The so-called homodesmotic reactions (involving the π-electron molecules of interest, and a set of reference molecules), treated with reliable methods of computational chemistry, B3LYP/6-31G(d) or B3LYP/6-311+G(2d,p) level of theory, provide a convenient general theoretical framework for calculating the stabilization energies. The present paper is a case study of the benzene molecule, as created from a set of nonstrained linear

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19

Kuznetsov, S. "Raman Analysis of Polyvinyl Chloride Degraded under Different Temperature Conditions." Bulletin of Science and Practice 10, no. 10 (2024): 42–48. http://dx.doi.org/10.33619/2414-2948/107/05.

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In this work, the Raman spectroscopy method was used to study changes in the composition of polyvinyl chloride (PVC) during its degradation. Traditionally, such changes are analyzed optically due to the fact that during degradation, polyene sequences of different lengths are formed in the PVC structure, which change many properties of the material, including optical ones. The Raman spectroscopy method chosen in this work is characterized by high accuracy and speed of analysis, as well as the ability to diagnose the presence of polyenes in extremely low concentrations. Undegraded PVC films and

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20

NAKASHIMA, TAKAYASU, TAKASHI YAMADA, HIDEKI HASHIMOTO, and TAKAYOSHI KOBAYASHI. "STRUCTURES AND OPTICAL PROPERTIES OF HYDRAZONES DERIVED FROM BIOLOGICAL POLYENES." International Journal of Modern Physics B 15, no. 28n30 (2001): 3893–96. http://dx.doi.org/10.1142/s0217979201008937.

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A set of hydrazone molecules was derived from a series of biological polyenes that have different polyene chain-lengths with common substituent group of 2,4-dinitrophenylhydrazine. Their structures were determined by high-resolution NMR spectroscopy as well as X-ray crystallography, and their optical properties were investigated by room and low temperature optical absorption spectroscopy. Among the derivatives so far synthesized, the one that has the shortest polyene chain (C13-DNPH) afforded single crystals without inversion symmetry, hence applicable for the second-order nonlinear optical de

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21

Robb, Kevin A., Soumitra V. Athavale, and Scott E. Denmark. "Unusual Kinetic Profiles for Lewis Base-Catalyzed Sulfenocyclization of ortho-Geranylphenols in Hexafluoroisopropyl Alcohol." Synlett 30, no. 14 (2019): 1656–61. http://dx.doi.org/10.1055/s-0039-1690111.

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The kinetic behavior of the Lewis base-catalyzed sulfenocyclization of polyenes in hexafluoroisopropyl alcohol (HFIP) was explored. The rate of reaction is not dependent on the electronic properties of the terminal nucleophile, suggesting that this capture step is not rate limiting. Additionally, fractional orders were observed for two of the reaction components. This intriguing profile appears unique to the polyene sulfenocyclization reaction and is not merely due to solvent effects.

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22

Omelchuk, Olga, Anna Tevyashova, Svetlana Efimova, et al. "A Study on the Effect of Quaternization of Polyene Antibiotics’ Structures on Their Activity, Toxicity, and Impact on Membrane Models." Antibiotics 13, no. 7 (2024): 608. http://dx.doi.org/10.3390/antibiotics13070608.

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Polyene antibiotics have been used in antifungal therapy since the mid-twentieth century. They are highly valued for their broad spectrum of activity and the rarity of pathogen resistance to their action. However, their use in the treatment of systemic mycoses often results in serious side-effects. Recently, there has been a renewed interest in the development of new antifungal drugs based on polyenes, particularly due to the emergence of highly dangerous pathogenic strains of fungi, such as Candida auris, and the increased incidence of mucormycosis. Considerable understanding has been establi

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23

Bobek, Jan, Eliška Filipová, Natalie Bergman, et al. "Polyenic Antibiotics and Other Antifungal Compounds Produced by Hemolytic Streptomyces Species." International Journal of Molecular Sciences 23, no. 23 (2022): 15045. http://dx.doi.org/10.3390/ijms232315045.

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Streptomyces are of great interest in the pharmaceutical industry as they produce a plethora of secondary metabolites that act as antibacterial and antifungal agents. They may thrive on their own in the soil, or associate with other organisms, such as plants or invertebrates. Some soil-derived strains exhibit hemolytic properties when cultivated on blood agar, raising the question of whether hemolysis could be a virulence factor of the bacteria. In this work we examined hemolytic compound production in 23 β-hemolytic Streptomyces isolates; of these 12 were soil-derived, 10 were arthropod-assoc

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24

Mann, Brian E. "Fluxionality of polyene and polyenyl metal complexes." Chemical Society Reviews 15, no. 2 (1986): 167. http://dx.doi.org/10.1039/cs9861500167.

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25

HAMMOND, S. M., P. A. LAMBERT, and B. N. KLIGER. "The Mode of Action of Polyene Antibiotics; Induced Potassium Leakage in Candida albicans." Microbiology 81, no. 2 (2000): 325–30. http://dx.doi.org/10.1099/00221287-81-2-325.

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Summary: With a liquid membrane potassium-sensitive electrode it was shown that lethal concentrations of the polyene antibiotics amphotericin B, candicidin and nystatin caused leakage of 90% of non-bound potassium ions from Candida albicans. Accurate and rapid determinations of rates of potassium leakage were made directly in suspensions of Candida. Leakage patterns for the three polyenes were very similar, suggesting a common site of action. Differences were noted in the rates of potassium efflux with organisms from cultures of differing ages.

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26

Pavic, Aleksandar, Zoran Stojanovic, Marina Pekmezovic, et al. "Polyenes in Medium Chain Length Polyhydroxyalkanoate (mcl-PHA) Biopolymer Microspheres with Reduced Toxicity and Improved Therapeutic Effect against Candida Infection in Zebrafish Model." Pharmaceutics 14, no. 4 (2022): 696. http://dx.doi.org/10.3390/pharmaceutics14040696.

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Immobilizing antifungal polyenes such as nystatin (Nys) and amphotericin B (AmB) into biodegradable formulations is advantageous compared to free drug administration providing sustained release, reduced dosing due to localized targeting and overall reduced systemic drug toxicity. In this study, we encapsulated Nys and AmB in medium chain length polyhydroxyalkanoates (mcl-PHA) microspheres (7–8 µm in diameter). The obtained formulations have been validated for antifungal activity in vitro against a panel of pathogenic fungi including species of Candida, Aspergillus, Microsporum and Trichophyton

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27

Chen, Chaoyang, Jing Yu, Chuting Zhang, Xu Ye, and Andy H. Shen. "Nature of Pigments in Orange and Purple Coloured Chinese Freshwater Cultured Pearls: Insights from Experimental Raman Spectroscopy and DFT Calculations." Minerals 13, no. 7 (2023): 959. http://dx.doi.org/10.3390/min13070959.

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Pearls, a well-known organic gemstone, are popular for their attractive lustre and rich colour. The pigmentation and colour of pearls have never been clearly explained. Understanding the pigments and colour origin of pearls can be a guide for artificial cultivation and rational conservation. In this study, Chinese freshwater cultured pearls were collected as research samples. The appearance and colour characteristics of pearls were characterised using D65 standard light source photography and UV–Vis spectroscopy, the molecular structure of the pigments in the pearls was characterised using Ram

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28

HAMMOND, S. M., P. A. LAMBERT, and B. N. KLIGER. "The Mode of Action of Polyene Antibiotics; Induced Entry of Hydrogen Ions as a Consequence of Polyene Action on the Cell Membrane of Candida albicans." Microbiology 81, no. 2 (2000): 331–36. http://dx.doi.org/10.1099/00221287-81-2-331.

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Summary: The polyene antibiotic candicidin is a potent antifungal agent acting upon the cell membrane of Candida albicans. Destruction of selective permeability by polyenes allows cations to leak into the environment and permits the entry of protons to neutralize the charge so created, causing internal acidification. Quantitive studies on proton entry reveal that K+ leakage alone is not sufficient to account for the degree of acidification recorded. Extracts of untreated C. albicans, when acidified to the same extent, precipitated. Electron micrographs of candicidin treated C. albicans cells c

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29

Vandeputte, Patrick, Guy Tronchin, Thierry Bergès, Christophe Hennequin, Dominique Chabasse, and Jean-Philippe Bouchara. "Reduced Susceptibility to Polyenes Associated with a Missense Mutation in the ERG6 Gene in a Clinical Isolate of Candida glabrata with Pseudohyphal Growth." Antimicrobial Agents and Chemotherapy 51, no. 3 (2006): 982–90. http://dx.doi.org/10.1128/aac.01510-06.

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ABSTRACT Little information is available about the molecular mechanisms responsible for polyene resistance in pathogenic yeasts. A clinical isolate of Candida glabrata with a poor susceptibility to polyenes, as determined by disk diffusion method and confirmed by determination of MIC, was recovered from a patient treated with amphotericin B. Quantitative analysis of sterols revealed a lack of ergosterol and an accumulation of late sterol intermediates, suggesting a defect in the final steps of the ergosterol pathway. Sequencing of CgERG11, CgERG6, CgERG5, and CgERG4 genes revealed exclusively

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30

Sultanova, G. H., T. J. Pashazade, and Kh M. Kasumov. "Analysis of Spectral Characteristics of Certain Polyene Antibiotics in the Presence of Dmso and Cholesterol." Antibiot Khimioter = Antibiotics and Chemotherapy 68, no. 11-12 (2024): 10–18. http://dx.doi.org/10.37489/0235-2990-2023-68-11-12-10-18.

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This work presents ultraviolet (UV) spectra of various concentrations of polyene antibiotics. The spectra of Levorin and Amphotericin B diﬀer in three main absorption maxima. The maximum absorption spectra of antibiotics vary in the range of 370–430 nm. UV absorption spectra reﬂect the characteristic spectrum of polyenes belonging to this class. Amphotericin B and Levorin in combination with cholesterol lower the maximum of the UV absorption spectra. Analysis of the obtained results shows that cholesterol molecules, combining with double-bond systems of Amphotericin B and Levorin, gradually re

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31

Rettig, Wolfgang, and Marina Dekhtyar. "Merocyanines: polyene–polymethine transition in donor–acceptor-substituted stilbenes and polyenes." Chemical Physics 293, no. 1 (2003): 75–90. http://dx.doi.org/10.1016/s0301-0104(03)00297-0.

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32

De Poire, Eimear, Niamh Stephens, Bernard Rawlings, and Patrick Caffrey. "Engineered Biosynthesis of Disaccharide-Modified Polyene Macrolides." Applied and Environmental Microbiology 79, no. 19 (2013): 6156–59. http://dx.doi.org/10.1128/aem.02197-13.

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ABSTRACTRecent work has uncovered genes for two glycosyltransferases that are thought to catalyze mannosylation of mycosaminyl sugars of polyene macrolides. These two genes arenypYfromPseudonocardiasp. strain P1 andpegAfromActinoplanes caeruleus. Here we analyze these genes by heterologous expression in various strains ofStreptomyces nodosus, producer of amphotericins, and inStreptomyces albidoflavus, which produces candicidins. The NypY glycosyltransferase converted amphotericins A and B and 7-oxo-amphotericin B to disaccharide-modified formsin vivo. The enzyme did not act on amphotericin ana

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33

Hogan, Mark, Yuhao Song, Jimmy Muldoon, and Patrick Caffrey. "Generation of New Glycoanalogues of Polyene Antibiotics by Synthetic Biology—Testing Current Technical Boundaries." SynBio 2, no. 1 (2024): 31–55. http://dx.doi.org/10.3390/synbio2010003.

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A number of antifungal drugs are based on polyene macrolides that cause severe side effects. Most of these compounds contain a single aminodeoxysugar, D-mycosamine. Toxicity can be reduced by increasing the extent of glycosylation. The aromatic heptaene 67-121C and two analogues of the degenerate heptaene nystatin have a second sugar attached to the C4′ hydroxyl of mycosamine. Another nystatin analogue has L-digitoxose as a second sugar attached to C35 on the macrolactone ring. The pentaene selvamicin has 4-O-methyl-L-digitoxose at C27, the equivalent position. To assist the production of new

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34

Tevyashova, Anna, Svetlana Efimova, Alexander Alexandrov, et al. "Semisynthetic Amides of Amphotericin B and Nystatin A1: A Comparative Study of In Vitro Activity/Toxicity Ratio in Relation to Selectivity to Ergosterol Membranes." Antibiotics 12, no. 1 (2023): 151. http://dx.doi.org/10.3390/antibiotics12010151.

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Polyene antifungal amphotericin B (AmB) has been used for over 60 years, and remains a valuable clinical treatment for systemic mycoses, due to its broad antifungal activity and low rate of emerging resistance. There is no consensus on how exactly it kills fungal cells but it is certain that AmB and the closely-related nystatin (Nys) can form pores in membranes and have a higher affinity towards ergosterol than cholesterol. Notably, the high nephro- and hemolytic toxicity of polyenes and their low solubility in water have led to efforts to improve their properties. We present the synthesis of

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35

Oostenbrug, Gerard S., Ronald P. Mensink, Monique D. M. Al, Adriana C. van Houwelingen, and Gerard Hornstra. "Maternal and neonatal plasma antioxidant levels in normal pregnancy, and the relationship with fatty acid unsaturation." British Journal of Nutrition 80, no. 1 (1998): 67–73. http://dx.doi.org/10.1017/s0007114598001780.

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During pregnancy, maternal plasma concentrations of the peroxidation-susceptible polyunsaturated fatty acids (polyenes) increase. In addition, the proportion of polyenes is higher in neonatal plasma than in maternal plasma. To study whether these increased amounts of polyenes affect antioxidant levels, we measured lipid-soluble antioxidants in maternal and neonatal plasmas obtained during thirty-five normal pregnancies. These values were then related to the degree of phospholipid-fatty acid unsaturation. Maternal plasma levels of tocopherols and lutein increased during pregnancy, as assessed a

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Lee, Alex J., Joseph Hammond, Jeffrey Sheridan, Simon Swift, Andrew B. Munkacsi, and Silas G. Villas-Boas. "Antifungal Activity of Disalt of Epipyrone A from Epicoccum nigrum Likely via Disrupted Fatty Acid Elongation and Sphingolipid Biosynthesis." Journal of Fungi 10, no. 9 (2024): 597. http://dx.doi.org/10.3390/jof10090597.

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Multidrug-resistant fungal pathogens and antifungal drug toxicity have challenged our current ability to fight fungal infections. Therefore, there is a strong global demand for novel antifungal molecules with the distinct mode of action and specificity to service the medical and agricultural sectors. Polyenes are a class of antifungal drugs with the broadest spectrum of activity among the current antifungal drugs. Epipyrone A, a water-soluble antifungal molecule with a unique, linear polyene structure, was isolated from the fungus Epiccocum nigrum. Since small changes in a compound structure c

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37

Ellis, David. "Amphotericin B: spectrum and resistance." Journal of Antimicrobial Chemotherapy 49, suppl_1 (2002): 7–10. http://dx.doi.org/10.1093/jac/49.suppl_1.7.

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Abstract Amphotericin B is a polyene macrolide antibiotic derived from the actinomycete Streptomyces nodosus. Of the 200 known polyene agents, amphotericin B is the only one with toxicities that are sufficiently limited to permit intravenous administration. All polyenes have a common mechanism of action in that they preferentially bind to ergosterol, the primary sterol in the fungal cell membrane. The consequence of this binding includes disruption of the osmotic integrity of the membrane, with leakage of intracellular potassium and magnesium, and also the disruption of oxidative enzymes in ta

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Song, Qi, Alex Singh, John E. McDonough, et al. "Predicting lung aging using scRNA-Seq data." PLOS Computational Biology 20, no. 12 (2024): e1012632. https://doi.org/10.1371/journal.pcbi.1012632.

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Age prediction based on single cell RNA-Sequencing data (scRNA-Seq) can provide information for patients’ susceptibility to various diseases and conditions. In addition, such analysis can be used to identify aging related genes and pathways. To enable age prediction based on scRNA-Seq data, we developed PolyEN, a new regression model which learns continuous representation for expression over time. These representations are then used by PolyEN to integrate genes to predict an age. Existing and new lung aging data we profiled demonstrated PolyEN’s improved performance over existing methods for a

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Kerber, Robert C., and Everett C. Ribakove. "Formation of iron carbonyl complexes of reactive polyenes from dihalides involving the free polyene." Organometallics 10, no. 8 (1991): 2848–53. http://dx.doi.org/10.1021/om00054a059.

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Vandeputte, Patrick, Guy Tronchin, Gérald Larcher, et al. "A Nonsense Mutation in the ERG6 Gene Leads to Reduced Susceptibility to Polyenes in a Clinical Isolate of Candida glabrata." Antimicrobial Agents and Chemotherapy 52, no. 10 (2008): 3701–9. http://dx.doi.org/10.1128/aac.00423-08.

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ABSTRACT Unlike the molecular mechanisms that lead to azole drug resistance, the molecular mechanisms that lead to polyene resistance are poorly documented, especially in pathogenic yeasts. We investigated the molecular mechanisms responsible for the reduced susceptibility to polyenes of a clinical isolate of Candida glabrata. Sterol content was analyzed by gas-phase chromatography, and we determined the sequences and levels of expression of several genes involved in ergosterol biosynthesis. We also investigated the effects of the mutation harbored by this isolate on the morphology and ultrast

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Duchowski, John K., and Bryan E. Kohler. "Optical Response of Linear Polyenes: Extension of the Simple Model for Linear Polyene Electronic Structure." Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals 256, no. 1 (1994): 449–57. http://dx.doi.org/10.1080/10587259408039275.

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Maia, Lenize F., Rafaella F. Fernandes, Gisele Lobo-Hajdu, and Luiz F. C. de Oliveira. "Conjugated polyenes as chemical probes of life signature: use of Raman spectroscopy to differentiate polyenic pigments." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2030 (2014): 20140200. http://dx.doi.org/10.1098/rsta.2014.0200.

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Polyenes, which are represented by carotenes, carotenoids and conjugated polyenals, are some of the most important targets for astrobiology, because they can provide strong evidence of the presence of organic compounds in the most extreme environments, such as on Mars. Raman spectroscopy has been used as the main analytical tool in the identification of such compounds, for the greatest variety of living species, from microorganisms to animals and plants. However, using only the position of the characteristic Raman bands can lead to errors in tentatively identifying chemicals. In this work, we

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Shvedova, L. A., A. S. Tatikolov, Zh A. Krasnaya, and V. A. Kuz'min. "Photochemistry of ketocyanin dye ? polyenic bis-?,??-amino ketones substituted in the polyene chain." Bulletin of the Academy of Sciences of the USSR Division of Chemical Science 39, no. 7 (1990): 1369–75. http://dx.doi.org/10.1007/bf00957840.

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Jalmakhanbetova, R. I., Ye M. Suleimen, I. H. Eissa, et al. "Isolation and biological evaluation of roseofungin and its cyclodextrin inclusion complexes." Bulletin of the Karaganda University. "Chemistry" series 100, no. 4 (2020): 35–44. http://dx.doi.org/10.31489/2020ch4/35-44.

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Roseofungin belongs to polyene antibiotics which is more active and less toxic comparing other polyenes of this group. Roseofungin was isolated from Actinomyces roseoflavus var. Roseofungini using different chro-matographic techniques and for the first time, the complexation of roseofungin with α-, β- and γ-cyclodextrin derivatives was performed. The binding patterns of the resulted complexes were studied in silico using mo-lecular docking techniques. The best binding mode was for roseofungin against γ-CD with an affinity value of ˗42.98 kcal/mol. The proposed binding mode of roseofungin again

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Chen, Chaoyang, Jing Yu, Xu Ye, and Andy H. Shen. "Deciphering the Color Origin of Pink Conch Pearl Using Nondestructive Spectroscopies and DFT Calculations." Minerals 13, no. 6 (2023): 811. http://dx.doi.org/10.3390/min13060811.

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Conch pearl is a calcareous concretion produced by the Queen conch mollusk and is of extremely high economic value. Its attractive pink color has remained a mystery for hundreds of years. This difficulty limits the development of cultivation and preservation technology of conch pearl. Due to its super-high value, it is generally impossible to use destructive chemical analysis methods. Here, various nondestructive spectroscopic analysis methods and theoretical calculations were used to reveal the color origin of pink conch pearl. The experimental Raman and UV-Vis spectroscopies were used to cha

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Barrett, Anthony, Tsz-Kan Ma, and Thomas Mies. "Recent Developments in Polyene Cyclizations and Their Applications in Natural Product Synthesis." Synthesis 51, no. 01 (2018): 67–82. http://dx.doi.org/10.1055/s-0037-1610382.

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Cascade polyene cyclization reactions are highly efficient and elegant bioinspired transformations that involve simultaneous multiple bond constructions to rapidly generate complex polycyclic molecules. This review summarizes the most prominent work on a variety of cationic and radical cascade cyclizations and their applications in natural product synthesis published between 2014 and 2018.1 Introduction2 Cationic Polyene Cyclizations2.1 Lewis Acid Mediated Polyene Cyclizations2.2 Brønsted Acid Mediated Polyene Cyclizations2.3 Halogen Electrophile Initiated Polyene Cyclizations2.4 Sulfur Electr

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Starcke, Jan Hendrik, Michael Wormit, and Andreas Dreuw. "Nature of the lowest excited states of neutral polyenyl radicals and polyene radical cations." Journal of Chemical Physics 131, no. 14 (2009): 144311. http://dx.doi.org/10.1063/1.3246350.

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Argüelles, Alejandra, Ruth Sánchez-Fresneda, José P. Guirao-Abad, José Antonio Lozano, Francisco Solano, and Juan-Carlos Argüelles. "Insight into the Antifungal Effects of Propolis and Carnosic Acid—Extension to the Pathogenic Yeast Candida glabrata: New Propolis Fractionation and Potential Synergistic Applications." Journal of Fungi 9, no. 4 (2023): 442. http://dx.doi.org/10.3390/jof9040442.

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Fungi have traditionally been considered opportunistic pathogens in primary infections caused by virulent bacteria, protozoan, or viruses. Consequently, antimycotic chemotherapy is clearly less developed in comparison to its bacterial counterpart. Currently, the three main families of antifungals (polyenes, echinocandins, and azoles) are not sufficient to control the enormous increase in life-threatening fungal infections recorded in recent decades. Natural substances harvested from plants have traditionally been utilized as a successful alternative. After a wide screening of natural agents, w

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LIPSHUTZ, B. H., and C. LINDSLEY. "ChemInform Abstract: A Streamlined Route to Highly Conjugated, all-(E) Polyenes Characteristic of Oxo Polyene Macrolide Antibiotics." ChemInform 28, no. 36 (2010): no. http://dx.doi.org/10.1002/chin.199736273.

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McGraw, Kevin J., and Mary C. Nogare. "Distribution of unique red feather pigments in parrots." Biology Letters 1, no. 1 (2005): 38–43. http://dx.doi.org/10.1098/rsbl.2004.0269.

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In many birds, red, orange and yellow feathers are coloured by carotenoid pigments, but parrots are an exception. For over a century, biochemists have known that parrots use an unusual set of pigments to produce their rainbow of plumage colours, but their biochemical identity has remained elusive until recently. Here, we use high-performance liquid chromatography to survey the pigments present in the red feathers of 44 species of parrots representing each of the three psittaciform families. We found that all species used the same suite of five polyenal lipochromes (or psittacofulvins) to colou

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