Relevant bibliographies by topics / Lactonization

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Lactonization'

Author: Grafiati
Published: 4 June 2021
Last updated: 22 February 2025

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Journal articles on the topic "Lactonization"

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Obara, Robert, Jacek Łyczko, and Antoni Szumny. "Enantioselective Lactonization of 3,3,6-Trimethyl-4(E)-heptenoic Acid Esters." Journal of Chemistry 2018 (December 2, 2018): 1–8. http://dx.doi.org/10.1155/2018/6135281.

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Studies on the use of lactonization in the asymmetric synthesis of 6,6-dimethyl-4-isopropyl-3-oxabicyclo[3.1.0]hexan-2-one were described. An asymmetrically induced lactonization reaction was performed on 3,3,6-trimethyl-4(E)-heptenoic acid esters (1) and enantiomerically pure alcohols such as (−)-menthol (a), (+)-menthol (b), (−)-borneol (c), (+)-isomenthol (d), (−)-isopinocampheol (e), and (S)-(−)-1-(2-bornylphenyl)-1-ethanol (f). The enantiomerically pure alcohols that were used as ancillary chiral substances were characterized by markedly different values of induction power; menthol (a, b), borneol (c), and phenetyl alcohol (f) performed better in asymmetric δ-lactonization, whereas isomenthol (d) and isopinocampheol (e) tended to favor asymmetric γ-lactonization.
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Takakura, Ryoya, Kazuho Ban, Hironao Sajiki, and Yoshinari Sawama. "Platinum-on-Carbon-Catalyzed Aqueous Oxidative Lactonization of Diols by Using Molecular Oxygen." Synlett 30, no. 16 (August 27, 2019): 1919–23. http://dx.doi.org/10.1055/s-0037-1611917.

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A lactonization of various diols catalyzed by platinum on carbon (Pt/C) in water under an atmosphere of molecular oxygen was developed. Derivatives of 1,4- 1,5- and 1,6-diols were transformed into the corresponding five-, six-, and seven-membered lactones by the present oxidative lactonization method.
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Gao, Wen-Chao, Zi-Yue Xiong, Shafigh Pirhaghani, and Thomas Wirth. "Enantioselective Electrochemical Lactonization Using Chiral Iodoarenes as Mediators." Synthesis 51, no. 01 (October 25, 2018): 276–84. http://dx.doi.org/10.1055/s-0037-1610373.

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The enantioselective electrochemical lactonization of diketo acid derivatives using chiral iodoarenes as redox mediators is reported for the first time. Good to high stereoselectivities are observed in the lactonization and also in intermolecular α-alkoxylations of diketo ester derivatives. This enantioselective process was then adapted to an electrochemical flow microreactor where only small amounts of supporting electrolyte were necessary.
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Virkki, Heli, Antti Vuori, and Tapani Vuorinen. "Intramolecular Lactonization of Poly(α-hydroxyacrylic acid): Kinetics and Reaction Mechanism." Journal of Polymers 2015 (September 28, 2015): 1–10. http://dx.doi.org/10.1155/2015/157267.

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Poly(α-hydroxyacrylic acid), PHA, is one of the few polymers with biodegradable properties used in mechanical pulp bleaching to stabilize hydrogen peroxide. A new method for the in situ follow-up of the lactone ring formation of PHA has been developed. The results have further been applied to describe the reaction kinetics of the lactonization and hydrolysis reactions through parameter estimation. In addition, the reaction mechanism is elucidated by multivariate data analysis. Satisfactory identification and semiquantitative separation of the lactone ring as well as the acyclic (carboxyl and hydroxyl groups) forms have been established by 1H NMR in the pH range of 1–9. The lactonization reaction approaching equilibrium can be described by pseudo-first-order kinetics in the pH range of 1–6. The rate constants of the pseudo-first-order kinetic model have been estimated by nonlinear regression. Due to the very low rates of lactonization as well as the weak pH dependency of the reaction, an addition-elimination mechanism is proposed. Additionally, the presence of a transient reaction intermediate during lactonization reaction could be identified by subjecting the measurement data to multivariate data analysis (PCA, principal component analysis). A good correlation was found between the kinetic and the PCA models in terms of model validity.
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Cenciarelli, Fabia, Giuseppe Falini, Demetra Giuri, and Claudia Tomasini. "Controlled Lactonization of o-Coumaric Esters Mediated by Supramolecular Gels." Gels 9, no. 4 (April 21, 2023): 350. http://dx.doi.org/10.3390/gels9040350.

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Fragrances are volatile organic compounds widely used in our daily life. Unfortunately, the high volatility required to reach human receptors reduces their persistency in the air. To contrast this effect, several strategies may be used. Among them, we present here the combination of two techniques: the microencapsulation in supramolecular gels and the use of profragrances. We report a study on the controlled lactonization of four esters derived from o-coumaric acid. The ester lactonization spontaneously occurs after exposure to solar light, releasing coumarin and the corresponding alcohol. To determine the rate of fragrance release, we compared the reaction in solution and in a supramolecular gel and we demonstrated that the lactonization reaction always occurs slower in the gel. We also studied the more suitable gel for this aim, by comparing the properties of two supramolecular gels obtained with the gelator Boc-L-DOPA(Bn)2-OH in a 1:1 ethanol/water mixture in different gelator concentration (0.2% and 1% w/v). The gel prepared with 1% w/v gelator concentration is stronger and less transparent than the other and was used for the profragrances encapsulation. In any case, we obtained a significative reduction of lactonization reaction in gel, compared with the same reaction in solution.
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Ceccherelli, P., M. Curini, M. C. Marcotullio, and O. Rosati. "Brominative lactonization in eudesmanes." Tetrahedron Letters 31, no. 21 (1990): 3071–74. http://dx.doi.org/10.1016/s0040-4039(00)89028-0.

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Rhee, Hakjune, Jaeyoung Ban, Saira Shabbir, Minkyung Lim, and Byunghoon Lee. "Synthesis of l-Ribose from d-Ribose by a Stereoconversion through Sequential Lactonization as the Key Transformation." Synthesis 49, no. 18 (June 20, 2017): 4299–302. http://dx.doi.org/10.1055/s-0036-1588857.

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l-Ribose, a key precursor of various l-nucleosides can only be synthesized from other sugars or other non-sugar precursors. Herein, the study involves the synthesis of naturally rare l-ribose from readily available d-ribose. Though, many synthetic strategies are developed to meet the increasing demands of l-ribose, seeking innovation, a synthesis employing sequential lactonization as the key transformation was explored. This novel conversion involves protection, oxidation, sequential lactonization, reduction with DIBAL-H, and deprotection.
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Ru-Jian, Yu, Chun-Yan Zhang, Huang Hai-Yan, Wang Pei, Wen-Yu Fu, Jian-Xin Cheng, and Yan-Shi Xiong. "Silver-mediated radical oxytrifluoromethylation of unsaturated carboxylic acids for the synthesis of γ-trifluoromethylthio lactones." Organic & Biomolecular Chemistry 20, no. 10 (2022): 2109–14. http://dx.doi.org/10.1039/d2ob00018k.

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Albarghouti, Ghassan, Ramesh Kotikalapudi, David Lankri, Viviana Valerio, and Dmitry Tsvelikhovsky. "Cascade Pd(ii)-catalyzed Wacker lactonization–Heck reaction: rapid assembly of spiranoid lactones." Chemical Communications 52, no. 15 (2016): 3095–98. http://dx.doi.org/10.1039/c5cc09923d.

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Brenna, Elisabetta, Francesco Dalla Santa, Francesco G. Gatti, Giuseppe Gatti, and Davide Tessaro. "Exploiting the vicinal disubstituent effect on the diastereoselective synthesis of γ and δ lactones." Organic & Biomolecular Chemistry 17, no. 4 (2019): 813–21. http://dx.doi.org/10.1039/c8ob02715c.

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Dissertations / Theses on the topic "Lactonization"

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Huang, Lei [Verfasser], and Andreas [Akademischer Betreuer] Liese. "New biocatalytic approaches for lactonization and lactamization / Lei Huang ; Betreuer: Andreas Liese." Hamburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2018. http://d-nb.info/1172813000/34.

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Brown, Loren. "Rapid Synthesis, Characterization, and Catalytic Function of Rhodium(III) and Iridium(III) Chloro-bridged Dimers." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/89732.

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Rh(III) and Ir(III) dimeric complexes with tunable cyclopentadienyl (Cp) rings have proven versatile for both catalysis and as synthetic precursors. An efficient microwave method to synthesize Rh(III) and Ir(III) dimeric complexes [(η5-ring)MCl]2(μ2-Cl)2, (where (η5-ring)MCl = (η5-Me4C5R)Rh(III)Cl or (η5-Me4C5R)Ir(III)Cl) was developed. A modular design for the substituted cyclopentadienes HC5Me4R was based on Grignard reactions of 2,3,4,5-tetramethylcyclopent-2-en-1-one (R = alkyl, 12 examples; R = aryl, 3 examples) or by SNAr reactions of potassium tetramethylcyclopentadienide with perfluoroarenes (R = perfluoroaryl, 3 examples). Reaction of the Me4CpHR ligands with [M(COD)](μ2-Cl)2 (M = Rh, Ir; COD = 1,5-cyclooctadiene) produced the dimeric complexes [Cp*RMCl]2(μ2-Cl)2 in moderate to excellent yield. The resulting dimers were characterized by nuclear magnetic resonance (NMR) spectroscopy, single-crystal X-ray diffraction (XRD), high-resolution mass spectrometry (HRMS), elemental analysis, and examined as catalysts for oxidative lactonization of 1,4- and 1,5-diols. Oxidative lactonization of 1,4-butanediol to afford γ-butyrolactone proceeded selectively and efficiently using [(η5-Me4C5R)IrCl]2(μ2-Cl)2 as the catalyst. Several R substituents were tested to assess electronic substituent effects. The most active complex contained an electron donating group, R = CHMe2 and successfully catalyzed the formation of diols to lactones across a range of 1,4- and 1,5-diols, generally in high yield. Computational analysis of the rate-determining b-hydrogen elimination reactions provided an atomistic account of observed trends in reaction yield and selectivity as a function of substrate structure, while accounting neatly for the observed selective formation of lactones (vs. succinaldehyde) in the transfer dehydrogenation of 1,4-butyrolactone.
Doctor of Philosophy
Rhodium(III) and iridium(III) complexes are useful synthetic precursors, catalysts, and biologically active compounds. This dissertation explores a rapid synthesis of these metal complexes and their subsequent catalytic applications with 1,4- and 1,5-diols. The oxidative lactonization of diols with rhodium and iridium complexes is an attractive one-pot synthesis, opening a variety of lactones to be produced. Structural studies involving novel fluorinated rhodium and iridium chloro-bridged dimers are discussed in detail.
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Belletti, Giada. "Organocatalytic Enantioselective Vinylogous Aldol-Lactonization Cascade Reaction of 3-Alkylidene Oxindoles to Trifluoromethyl Ketones." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14463/.

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In this work, an highly enantioselective vinylogous aldol-lactonization cascade reaction of 3-alkylidene oxindole to α,β-unsaturated trifluoromethyl ketone, promoted by bifunctional organocatalysts, is presented. The reaction proceed through 1,2-addition followed by cascade lactonization to afford an unsaturated lactone bearing a chiral trifluoromethylated tetrasubstituted carbon stereocenter with high enantioselectivity and moderate yield. Nevertheless, also the two E/Z isomers of the correspondent 1,2-addition product are obtained.
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Matla, Andrea Slava. "Expanding the scope of the nucleophile catalyzed aldol lactonization (NCALl) process and transformations of the resulting beta-lactones." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2676.

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Walters, Jennifer Caroll. "NITROGEN-LIGATED (POLY)CATIONIC IODINE(III) REAGENTS: PLATFORMS FOR REAGENT DEVELOPMENT AND DIVERSE HETEROCYCLIC SYNTHESES." Diss., Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/558365.

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Chemistry
Ph.D.
Hypervalent iodine (HVI) reagents are easily accessed, highly tunable, mild, selective oxidants that are less toxic and more environmentally benign compared to their heavy metal counterparts. λ3-Iodanes, which possess an iodine center bound to one aryl substituent and two heteroatom ligands, have been the subject of recent interest due to their electrophilicity and hypernucleofugality. A central focus of the Wengryniuk laboratory has been the further development and application of a class of electrostatically activated (bis)cationic nitrogen-ligated HVI (N-HVI) reagents. N-HVIs feature datively bound heterocyclic ligands which results in dramatically enhanced electrophilicity and redox potentials. Despite being a highly tunable platform for reagent development, N-HVIs remain a relatively underexplored class of λ3-iodanes. This dissertation focuses on demonstrating N-HVI’s synthetic potential and developing novel variants to enhance their synthetic utility. Chapter 1 of this dissertation serves as a general background and introduction to nitrogen-ligated HVI reagents. Chapter 2 outlines our efforts in N-HVI library expansion, novel syntheses, and characterization. With a library of 33 novel N-HVIs in hand, ligand effects on N-HVI reactivity were analyzed via qualitative and quantitative methods. Chapter 3 describes our first synthetic application of N-HVIs in the development of novel oxidative rearrangements of simple and complex cyclic alcohols. This chapter describes the chemoselective ring expansion of 2° and 3° cyclic alcohols accessing medium-sized cyclic acetal products in good to excellent yields with applicability to Complexity-to-Diversity (CTD) efforts. Chapter 4 demonstrates our initial efforts toward the development of another synthetic method where the functionalized N-heterocyclic ligands of the N-HVIs can be regioselectivity incorporated into a molecule following N-HVI activation of an olefin. The pyridinium lactone salts formed from olefinic acids were isolated in excellent yields via simple trituration, supplying a synthetically useful functional handle that was easily derivatized via known methods. These four chapters summarize the current state of the research with nitrogen-ligated HVI salts, expand upon our initial publications to highlight the development of novel heterocyclic syntheses, and provide a useful guide to further explore the reactivity of these tunable reagents.
Temple University--Theses
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Oh, Seongho. "Optimization and extensions of the nucleophile catalyzed aldol-lactonization (NCAL) process for bicyclic beta-lactone synthesis: applications to piperidine, pyrrolidine, and gamma-lactam-fused beta-lactones." Texas A&M University, 2003. http://hdl.handle.net/1969.1/3961.

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The intramolecular nucleophile catalyzed aldol-lactonization (NCAL) process was optimized successfully. A variety of C9-acylated cinchona alkaloids were synthesized and used for NCAL reactions with non-activated aldehydes. New pyridinium salts, derivatives of Mukaiyama’s reagent, led to marked improvements in efficiency for the catalytic, asymmetric NCAL process while maintaining high enantioselectivity. Larger scale versions of the catalytic, asymmetric NCAL reaction were also developed allowing practical access to chiral bicyclic b-lactones. As an extension of the intramolecular NCAL process, pyrrolidine and piperidine fused blactones were synthesized. Simple g-lactam fused b-lactones were synthesized as a model study for omuralide, salinosporamide A, and derivative synthesis. Synthesis of asubstituted aldehyde acids was extensively studied but steric effects from both acid and amine moieties led to great difficulties in this approach.
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Gelis, Coralie. "Développement de réactions énantiosélectives organocatalysées pour la synthèse de molécules cycliques énantioenrichies." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS430.

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Le développement de méthodes de synthèse asymétrique est très important pour l’accès à des molécules à visées thérapeutiques. Dans ce contexte, nous nous sommes intéressés à l’utilisation d’organocatalyseurs chiraux pour la synthèse de molécules cycliques énantioenrichies. Dans une première partie sont présentées des réactions de cycloadditions formelles (3+2), (4+2) et (4+3) à partir d’ènecarbamates ou de diènecarbamates catalysées par des acides phosphoriques chiraux. Ces derniers étant bifonctionnel, ils permettent l’activation des deux partenaires de cycloaddition menant à la synthèse d’indolines, de 2,3-dihydrobenzofuranes, de benzoquinones carbonannulées, de cyclohepta[b]indoles et de tétrahydroquinolines de façon hautement stéréosélective. Dans une seconde partie, nous nous sommes intéressés à l’utilisation de composés d’iode hypervalent chiraux comme organocatalyseurs. En effet, ces composés présentent une réactivité intéressante tout en étant stable et faiblement toxique. Ainsi, leur utilisation dans une réaction de lactonisation à partir de substrats flexibles a permis l’obtention de divers hétérocycles avec de bons résultats
The development of new enantioselective methodologies is essential for the synthesis of bioactive compounds. In this context, we were interested in using organocatalysts for the synthesis of enantioenriched cyclic molecules. In a first part will be describe chiral phosphoric acid catalyzed (3+2), (4+2) and (4+3) formal cycloadditions using enecarbamate or dienecarbamate. These catalysts are bifunctional and can interact with both cycloaddition partners leading to the synthesis of 2,3-dihydrobenzofuranes, carboannulated benzoquinones, cyclohepta[b]indoles and tetrahydroquinolines with high stereocontrol. In a second phase, we were interested in using chiral hypervalent iodine as organocatalyst. Theses compounds present interesting reactivity while being stable and not very toxic. Their use permits us to develop a lactonisation starting from flexible substrate and led to the synthesis of various heterocycles with good results
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Lefèvre, Antoine. "Oxydation électrochimique de fonctions 1,3-dicarbonylées pour la synthèse de squelettes de diterpénoïdes de type abiétanes aromatiques par bicyclisation et de γ-lactones par couplage avec des styrènes." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASF084.

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Les abiétanes diterpénoïdes aromatiques sont une famille de composés naturels qui sont suspectés d'avoir de nombreuses vertus thérapeutiques. C'est pourquoi, les chimistes organiciens ont cherché à développer différentes stratégies pour atteindre leurs squelettes. L'une d'entre elles implique la polycyclisation de polyènes par oxydation de β-céto-ester avec du manganèse triacétate en quantité surstoechiométrique dans l'acide acétique. Or, ces dernières années, l'électrosynthèse est apparue comme un outil puissant permettant le développement d'oxydation en utilisant des quantités catalytiques de réactifs. C'est ainsi que de nombreuses équipes ont décrit des méthodologies permettant l'oxydation anodique de composés 1,3-dicarbonylés. Nous avons donc envisagé de développer une version électrochimique de ces polycyclisations de Snider. Dans un premier temps, l'oxydation anodique de malonates en utilisant le ferrocène comme médiateur redox a permis la synthèse diastéréosélective de composés tricycliques ayant un squelette trans-décaline mais également de lactones bicycliques comme produits secondaires. Jusqu'à aujourd'hui ce type de structures polycycliques restaient inaccessibles par oxydation au manganèse triacétate. Notre méthodologie a été étendue aux groupements électro-attracteurs cyanoester, dinitrile et β-céto-esters mais également à une variété de cœurs aromatiques. Les cyclisations avec des hétéroaryles comme terminaison ont également été explorées. Ensuite des lactonisations intermoléculaires ont été effectuées, en effet il a été observé que le radical-malonate peut réagir avec des dérivés de styrène, puis cyclise par la suite, ce qui permet de former une variété de γ-lactones. Dans un second temps, il a été essayé de développer une version énantiosélective de la polycyclisation des abiétanes diterpénoïdes aromatiques. Tout d'abord en utilisant des 2-acétyles-imidazoles et 2-acétyles-thiazoles comme groupement initiateur de la cyclisation. En effet, en présence d'un catalyseur chiral, il est possible de réduire le potentiel redox de ces énols. Une fois le radical formé, une addition énantiosélective sur une double liaison pourrait avoir lieu. Cependant dans notre cas, seule la synthèse d'un produit non-désiré a été observée au lieu de la structure tricyclique. In fine, l'utilisation de la fonction β-céto-ester comme groupement électro-attracteur en présence d'une diamine a été essayée. L'objectif était de développer une version électrochimique de la catalyse SOMO développée par MacMillan, une fois que l'énamine correspondante est formée. Les recherches continuent aujourd'hui concernant ce type d'activation
Aromatic abietane diterpenoids are a family of natural compounds that are suspected to have numerous therapeutic effects. That is why organic chemist developed a lot of different strategies to reach their cores. One of them involve the polycyclizaton of polyenes initiated by the oxidation of β-keto-ester by manganese triacetate in substoichiometric amount in acetic acid. On the other hand, electrochemistry emerged as a powerful sustainable synthetic tool in organic chemistry, which avoids the use of external stoichiometric oxidant. Lately, number of research teams described methods for the anodic oxidation of 1,3-dicarbonyls. Therefore, we investigated the development of an electrochemical version of these Snider-type polycyclizations. In the first part of the thesis, conditions involving ferrocene-mediated oxidation of malonate were developed, which enable the diastereoselective formation of tricyclic structures with a trans-decalin core alongside bicyclic lactone by-products. Until nowadays these kinds of polycyclic structures remained inaccessible by manganese triacetate oxidation. This methodology was extended to cyanoester, dinitrile and β-keto-ester electron withdrawing groups alongside different aromatic cores. Cyclization with heteroaryle terminaison was also explored. Then intermolecular lactonizations were performed, indeed it was observed that malonate-radical could react with by styrene derivatives, followed by cyclization, which allow the formation of the desired γ-lactones. In the second part of the thesis, development of an enantioselective polycyclization of the aromatic abietane diterpenoids was attempted. First, by using 2-acetyl-imidiazole and 2-acetyl-thiazole as initiator of the cyclization. Indeed, in presence of the adequate chiral catalyst it is possible to reduce the redox potential of these enols. Then enantioselective addition on a double bond could occur. However, production of an undesired product was observed in our case instead of the polycyclic compound. In fine, use of β-keto-ester electron-withdrawing group in presence of diamine was attempted. The objective was to develop an enantioselective version of the SOMO catalysis described by MacMillan on the formed enamine. This activation mode is still studied
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LA, ROCCA PAOLO. "SYNTHESIS AND BIOLOGICAL EVALUATION OF NEW NEURAMINIDASE INHIBITORS DERIVED FROM SIALIC ACID AS POTENTIAL ANTIVIRAL AGENTS." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/604325.

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The development of new, potent and selective bacterial, viral and human sialidase (neuraminidase) inhibitors is an important issue to be pursued in order to achieve both useful therapeutical and biochemical tools. In fact, these hydrolytic enzymes can represent a good target since they play key roles in some physio-pathological processes by regulating the levels of sialic acid (such as the N-acetyl neuraminic acid; Neu5Ac) presents in glycoconjugates. In addition, in the design of inhibitors against a specific member of this class of enzymes is critical to take into account that these proteins share some common features such as the tridimensional structure of their catalytic domain, but, on the other hand, they show a very low sequence identity. Indeed, the only conserved residues are some active site amino acids essential for the catalytic mechanism. This thesis work was focused on the synthesis of hemagglutinin-neuraminidase (HN) inhibitors against the Newcastle virus (NDV), a member of the Paramyxoviridae family and strictly related to human parainfluenza viruses (hPIVs). NDV is a single-stranded RNA virus which could affect most species of both domestic and wild birds, causing significant and substantial economic losses in the poultry industry. To date, vaccination is the preferential instrument to border the infection, but when this procedure is not applicable, an efficient antiviral therapy could be the only useful way to control NDV outbreaks. At this purpose, the HN glycoproteins of paramyxoviruses represent an excellent target to be hit because they have some key roles in viral lifecycle: a) allowing viral attachment to the target cell; b) promoting the fusion process and, finally c) ensuring the release of the neo-synthesized virions. Over the past years, while some 2,3-unsaturated Neu5Ac derivatives (DANA derivatives) have been marketed as inhibitors against influenza virus neuraminidases (belonging to Orthomyxoviridae family), no compounds reach the clinical phase for paramyxoviruses treatment. In particular, few molecules have been developed for NDV-HN, and the N-trifluoroacetyl derivative of DANA (FANA) was still the best inhibitor until my thesis work. So, the necessity to find new, potent and possibly selective inhibitors against paramyxoviruses-HNs remain a key issue. At this purpose, the successful strategy, resulted fundamental to develop new NDV-HN inhibitors, was based on a multidisciplinary approach that combined the use of a) the chemical synthetic procedures, b) the computational docking studies and c) some biochemical activity assays. More in detail, the attention was directed to the study of two classes of inhibitors:  Some C5 or C4/C5 modified 2,3-unsaturated DANA derivatives, as reversible inhibitors.  Some scarcely investigated C2 modified 3,4-unsaturated Neu5Ac analogues, as irreversible ones. We finally reached satisfying results, regarding both classes of inhibitors: a) The understanding of the influence of the C5 N-perfluorinated substituents on the inhibitory activity of some 2,3-unsaturated DANA analogues, as potent and reversible NDV-HN inhibitors. b) The discovery of a new C5 N-perfluorinated inhibitor against NDV-HN as potent as FANA (the best NDV-HN inhibitor previously published) but more selective for NDV-HN towards human NEU3. c) The significant achievements of five new, potent and selective C4 and C5 modified 2,3-unsaturated DANA derivatives. All these compounds, combining the C4 azido or C4 p-toluensolfonamido group with the C5 N-perfluorinated chains, showed IC50 values in the nanomolar range; thus, they are up to 15-fold more potent than FANA. d) The set-up of more efficient synthetic procedures to achieve the 3,4-unsaturated Neu5Ac derivatives in high yields and β-anomeric stereoselectivity. e) The set-up of a smart and rapid method to unequivocally attribute the C2 configuration of the 3,4-unsaturated Neu5Ac inhibitors, via a 1,7-lactonization reaction. f) The mechanism elucidation of an unreported and unexpected chemical scrambling between the C4 and the C5 position of Neu5Ac derivatives (through a previously uncharacterized reaction intermediate). In addition, the rigid and induced fit docking simulation results permitted me to speculate on the interactions of the synthesized inhibitors with some active site amino acids, such as Lys236, a well know key residue involved in NDV-NH catalytic site activation mechanism and in fusion promotion activity. The comprehension of ligand/receptor interactions could lead to the development of molecules able to block, not only the neuraminidase activity of NDV-HN or other paramyxoviruses-HN, but also other viral functions mediated by these enzymes. Some of the obtained results allowed the publication of two scientific articles:  Rota, P., La Rocca, P., Piccoli, M., Montefiori, M., Cirillo, F., Olsen, L., Orioli, M., Allevi, P., and Anastasia, L. (2018) Potent Inhibitors against Newcastle Disease Virus Hemagglutinin-Neuraminidase, ChemMedChem 13, 236-240.  Rota, P., Papini, N., La Rocca, P., Montefiori, M., Cirillo, F., Piccoli, M., Scurati, R., Olsen, L., Allevi, P., and Anastasia, L. (2017) Synthesis and chemical characterization of several perfluorinated sialic acid glycals and evaluation of their in vitro antiviral activity against Newcastle disease virus, MedChemComm 8, 1505-1513.
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Shie, Chi-Rung, and 謝其榕. "Cell Surface Heparan Sulfate Oligosaccharides: Synthesis and Lactonization." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/21207955688928719951.

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Abstract:
博士
國立清華大學
化學系
96
硫酸乙醯肝素(heparan sulfate, HS)與肝素(heparin, HP)是屬於葡胺聚醣(glycosaminoglycan, GAG)的生物分子。兩者皆是具有負電荷性質的多醣體，主要的結構是由��1��4方式連接D式葡萄胺醣(GlcNH2)衍生物及��1��4方式連接D式葡萄醣酸(GlcA)或是L式艾杜醣酸(IdoA)。硫酸乙醯肝素廣佈於細胞表面及胞外纖維組織裡，另一方面肝素則是只由巨細胞(mast cell)分泌而得的。到目前為止已經被發現有許多生理反應或病毒的感染皆是透過和硫酸乙醯肝素的鍵結，然而由於硫酸乙醯肝素在自然界中不容易取得，所以很多的生物學家都採用由牛肺與豬腸提煉而得的肝素，來作為研究硫酸乙醯肝素與其他生物分子(例如:病毒、細菌、或生物體重要的蛋白質)間作用的機制，但是，硫酸乙醯肝素與肝素畢竟還是屬於兩種不同的個體，各自有屬於自己的結構特色，並不適合混為一談。因此，本論文將著重於如何使用化學合成來製備結構確定且成份均勻的硫酸乙醯肝素的寡醣體。 這篇論文大致上可分成十個章節，第一章主要是在描述細胞表面的醣類種類，並將重點著重在描述硫酸乙醯肝素與肝素兩者的結構與生物活性。第二章則是簡介目前幾位重量級醣類化學家對於合成硫酸乙醯肝素與肝素寡醣的工作。第三章則是提出關於在這個領域中我們想要解決的幾個問題及我們想要合成的目標分子，並試著將目標分子進行反合成分析。 第四章描述了我們對於構成硫酸乙醯肝素與肝素的單醣體建構單元的合成工作，我們經由七個步驟可以將D式葡萄糖轉變成我們所需要的糖予體。第五章則有系統的探討各種三氟甲磺酸金屬鹽催化苯亞甲基縮醛還原開環反應的位向選擇性，並且在氘取代還原劑的作用下進行了一系列的氘取代標幟實驗，並試著提出合理的反應機構。 第六章描述了我們如何由還原端來建構寡醣體的骨架，在遇到了一些問題以後，我們將合成策略改由非還原端來建立寡醣體的骨架，八醣體是本篇論文中所合成最長的寡醣單元。第七章是描述將連結單元接上寡醣體骨架以後，經由八個步驟就可以得到硫酸乙醯肝素的雙醣體、四醣體以及六醣體。最後，第八章提出了關於硫酸乙醯肝素內酯化反應的概念，並用硫酸乙醯肝素三醣體為例，證明了三醣體及其內酯化產物可以互換的想法。 第九章結論中，我們統整了第四到第八章的合成工作。第十章則是提供了在合成工作中所需要的實驗步驟與新產生化合物的詳細物理性質與光譜資料。
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Book chapters on the topic "Lactonization"

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Strukul, G., A. Gusso, and F. Pinna. "Enantioselective Lactonization of Cyclic Ketones with H2O2 Catalyzed by Complexes of Platinum(II)." In The Activation of Dioxygen and Homogeneous Catalytic Oxidation, 482. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4615-3000-8_73.

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Maier, M. E. "Lactonization." In Three Carbon-Heteroatom Bonds: Acid Halides; Carboxylic Acids and Acid Salts, 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-020-01371.

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Williams, A. C., and N. Camp. "By Lactonization." In Six-Membered Hetarenes with One Chalcogen, 1. Georg Thieme Verlag KG, 2003. http://dx.doi.org/10.1055/sos-sd-014-00635.

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Maier, M. E. "Mitsunobu Lactonization." In Three Carbon-Heteroatom Bonds: Acid Halides; Carboxylic Acids and Acid Salts, 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-020-01396.

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"lactonization, n." In Oxford English Dictionary. 3rd ed. Oxford University Press, 2023. http://dx.doi.org/10.1093/oed/5912410655.

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Maier, M. E. "Base-Induced Lactonization." In Three Carbon-Heteroatom Bonds: Acid Halides; Carboxylic Acids and Acid Salts, 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-020-01379.

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Maier, M. E. "Proton-Catalyzed Lactonization." In Three Carbon-Heteroatom Bonds: Acid Halides; Carboxylic Acids and Acid Salts, 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-020-01398.

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Williams, A. C., and N. Camp. "Lactonization of Hydroxy Esters." In Six-Membered Hetarenes with One Chalcogen, 1. Georg Thieme Verlag KG, 2003. http://dx.doi.org/10.1055/sos-sd-014-00637.

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Williams, A. C., and N. Camp. "Lactonization of Hydroxy Amides." In Six-Membered Hetarenes with One Chalcogen, 1. Georg Thieme Verlag KG, 2003. http://dx.doi.org/10.1055/sos-sd-014-00638.

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Williams, A. C., and N. Camp. "Reductive Lactonization of Naphthoquinones." In Six-Membered Hetarenes with One Chalcogen, 1. Georg Thieme Verlag KG, 2003. http://dx.doi.org/10.1055/sos-sd-014-00640.

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Conference papers on the topic "Lactonization"

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Stadelmann, Sacha, Stéphane Mayor, Roger Marti, and Marc Mathieu. "Depsipeptide cyclisation: Lactonization vs. Lactamisation." In 35th European Peptide Symposium. Prompt Scientific Publishing, 2018. http://dx.doi.org/10.17952/35eps.2018.166.

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Stywarni, Galuh Alya, Elvina Dhiaul Iftitah, and Arie Srihardyastutie. "Lactonization Castor Oil (Ricinus Communis) using Lipase B from Candida Antarctica Recombined Aspergillus oryzae as Bioflavor." In 2nd International Conference of Essential Oil Indonesia. SCITEPRESS - Science and Technology Publications, 2019. http://dx.doi.org/10.5220/0009955000370040.

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Fernandes, Talita de A., Boniek Gontijo Vaz, Marcos N. Eberlin, Alcides J. M. da Silva, and Paulo R. R. Costa. "Palladium catalyzed Heck-lactonization from orthoiodophenols and enoates: Synthesis of coumarins and the study of the mechanism by electrospray ionization mass spectrometry." In 14th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-14bmos-r0071-1.

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