Relevant bibliographies by topics / Lactone reduction

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

Academic literature on the topic 'Lactone reduction'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

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Journal articles on the topic "Lactone reduction"

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Plutno, A. B., I. D. Sham'yanov, and G. G. Galust'yan. "Reduction of the natural sesquiterpene lactone leucomisin." Chemistry of Natural Compounds 31, no. 1 (1995): 58–62. http://dx.doi.org/10.1007/bf01167572.

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Ishii, Hideki, Sergei V. Dzyuba, and Koji Nakanishi. "Lactone-free ginkgolides via regioselective DIBAL-H reduction." Organic & Biomolecular Chemistry 3, no. 19 (2005): 3471. http://dx.doi.org/10.1039/b509129b.

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Huneck, Siegfried, Jürgen Schmidt, and Andrea Porzel. "Zur Chemie der Roccellsäure / On the Chemistry of Roccellic Acid." Zeitschrift für Naturforschung B 49, no. 4 (1994): 561–68. http://dx.doi.org/10.1515/znb-1994-0420.

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The isomerization of roccellic acid to threo-roccellic acid has been investigated. Reduction of dimethyl roccellate with LiAlH4 gave the corresponding diol which yielded on oxidation with Jones' reagent two isomeric γ-lactones. 1-Methyl roccellic amide has been transformed by a photochemical reaction to the δ-lactone acaranoic acid. Two copper complexes of roccellimide have been prepared.
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Kataoka, Michihiko, Sakayu Shimizu, and Hideaki Yamada. "Stereospecific conversion of a racemic pantoyl lactone to D-(-)-pantoyl lactone through microbial oxidation and reduction reactions." Recueil des Travaux Chimiques des Pays-Bas 110, no. 5 (2010): 155–57. http://dx.doi.org/10.1002/recl.19911100504.

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Liu, Zhengchun, Alessandro Granata, Xinhua Shen, and Arthur S. Perlin. "Reactions of hydriodic acid with aldonolactones and n-alkanolactones. Interconversions between lactones and iodocarboxylic acids." Canadian Journal of Chemistry 70, no. 7 (1992): 2081–88. http://dx.doi.org/10.1139/v92-264.

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Aldonolactones containing from four to eight carbon atoms, and lactones of the related monohydroxy-n-alkanoic acids, were subjected to reaction with 57% hydriodic acid at 125 °C. As in the classical studies of Kiliani, the reduction of D-glycero-D-ido-heptono-1,4-lactone yielded mainly γ-heptanolactone. Analogously, the corresponding γ-alkanolactones were obtained as major products from the 1,4-lactones of the D-xylono-, D-allono-, and D-erythro-L-talo-octono configuration. Monoiodo-n-alkanoic acids were also formed in admixture with the lactones in all of these reactions. D-Erythrono-1,4-lact
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Kolt, R. J., D. Griller та D. D. M. Wayner. "Unsaturated spiro-γ-lactone formation by the dissociative reduction of bromoacetates". Tetrahedron Letters 31, № 52 (1990): 7539–40. http://dx.doi.org/10.1016/s0040-4039(00)97292-7.

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Xie, Minhui, Jianping Gao, Huiying Kang, et al. "Fabrication of effective oxygen reduction catalysts using lactone tofu as precursor." Journal of Electroanalytical Chemistry 850 (October 2019): 113395. http://dx.doi.org/10.1016/j.jelechem.2019.113395.

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Brito, Maria V., Ricardo A. Marques, Marcos C. Mattos та ін. "Semisynthesis and absolute configuration of a novel rearranged 19,20-δ-lactone (9βH)-pimarane diterpene". Acta Crystallographica Section C Structural Chemistry 74, № 8 (2018): 870–75. http://dx.doi.org/10.1107/s2053229618009452.

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Annonalide (3β,20-epoxy-3α,16-dihydroxy-15-oxo-7-pimaren-19,6β-olide, C20H26O6, 1) is the major (9βH)-pimarane diterpene isolated from tubers of Cassimirella ampla, and it exhibits cytotoxic properties upon interaction with ctDNA. We have prepared new derivatives of 1 by modification of the (9βH)-pimarane backbone and report here the semisynthesis and absolute configuration of a novel rearranged 19,20-δ-lactone (9βH)-pimarane. Our approach was the reduction of the carbonyl groups of 1 with sodium borohydride, at positions C15 (no stereoselectivity) and C3 (stereoselective reduction), followed
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Levine, Stewart J., Barbara Adamik, Feras I. Hawari, et al. "Proteasome inhibition induces TNFR1 shedding from human airway epithelial (NCI-H292) cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 289, no. 2 (2005): L233—L243. http://dx.doi.org/10.1152/ajplung.00469.2004.

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The type 1 55-kDa TNF receptor (TNFR1) is an important modulator of lung inflammation. Here, we hypothesized that the proteasome might regulate TNFR1 shedding from human airway epithelial cells. Treatment of NCI-H292 human airway epithelial cells for 2 h with the specific proteasome inhibitor clasto-lactacystin β-lactone induced the shedding of proteolytically cleaved TNFR1 ectodomains. Clasto-lactacystin β-lactone also induced soluble TNFR1 (sTNFR1) release from the A549 pulmonary epithelial cell line, as well as from primary cultures of human small airway epithelial cells and human umbilical
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Satō, Tsuguo. "Synthesis of optically active forms of the δ-lactone of 3,5-dihydroxydecanoic acid". Canadian Journal of Chemistry 65, № 12 (1987): 2732–33. http://dx.doi.org/10.1139/v87-454.

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Dissertations / Theses on the topic "Lactone reduction"

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Collins, Karl Daniel. "The development and application of radical and anionic cyclisations mediated by samarium(II) diodide and protic co-solvents." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/the-development-and-application-of-radical-and-anionic-cyclisations-mediated-by-samariumii-diodide-and-protic-cosolvents(0e807a8c-d40f-45bb-8d83-26e79ebe9388).html.

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The development of selective SmI2-H2O-mediated mono-reductions of cyclic-1,3-diesters to the corresponding 3-hydroxy acids is described. The reaction proceeds with complete selectivity for cyclic-1,3-diesters over acyclic esters. Sequential one-pot conjugate reduction-ester reduction of alkylidene cyclic-1,3-diesters is also reported. Furthermore, we describe the exploitation of the unusual ketyl radical intermediates formed via single electron reduction of the ester carbonyl in unprecedented 5-exo-trig cyclisations providing access to highly substituted, stereo-defined, cyclopentanols and cyc
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Hutt, Jean. "Synthese d'analogues de la vitamine d::(3) : synthese chirale de composes polyhydroxyles." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13326.

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La transformation de la cfarvone en quatre diastereoisomeres precurseurs du cycle a des dihydrovitamines et dihydrotachysterols est decrite dans la premiere partie. Par couplage d'un acetylure derive des cycles c/d de la vitamine d::(3) avec la cetone precurseur du cycle a, puis sa formation du systeme dienique a l'aide de titane a basse valence nous avons obtenu des dihydrotachysterols majoritairement. D'un autre cote, l'utilisation de sulfoxydes optiquement actifs dans l'intention de creer des centres hydroxyles chiraux et son application a la synthese du fragment polyhydroxyle de l'amphoter
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Parmar, Dixit. "Reductive cyclisations of lactones using SmI2 and H2O." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/reductive-cyclisations-of-lactones-using-smi2-and-h2o(533c0430-fd14-4a24-93f2-18a7fb27232f).html.

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Carbonyl reduction is a fundamental transformation that underpins synthetic chemistry. The re-routing of carbonyl reduction through less-conventional intermediates allows new selectivity and reactivity to be found in the resulting reaction space. We have shown for the first time that the unusual radical anions formed by electron transfer to the ester carbonyl group can be exploited in additions to alkenes. We have demonstrated that the reductive cyclisations of lactones, triggered by electron-transfer from SmI2-H2O, allow for highly decorated cyclopentane and cycloheptane ring systems to be co
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Fernandez, Anne-Marie. "Préparation de γ-butyrolactones γ-alkylées optiquement pures à partir de l'acide L-tartrique. Application à la synthèse totale de la L-bioptérine". Rouen, 1996. http://www.theses.fr/1996ROUES025.

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Une nouvelle méthode pour la préparation de gamma-butyrolactones optiquement pures est proposée. Une stratégie de synthèse donnant accès à deux types de chirons carbonylés (cétones et aldéhyde) a permis le développement de deux réactions hautement stéréosélectives créant ainsi un troisième centre stéréogénique : la réduction des cétones, (2R, 3R)-2,3-dipivaloxy-4-oxo alcanoates de méthyle par le borohydure de sodium dans le méthanol mène aux alcools correspondants (4R), avec des ee>98%, précurseurs des (2R,3S,4R)-2,3-dipivaloxy-4-alkylbutyrolactones. L'addition d'organomagnésiens sur l'aldéhyd
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Anderson, Scott Cameron. "Blood lactate reduction at three recovery intensities following severe rowing excercise." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26348.

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The purpose of this study was to observe the differences in rates of blood lactate reduction (BLR) at three recovery intensities (40% VO₂max, 60% V02max, and combined recovery ) when subjects are highly trained and aerobically fit. Eight well-trained oarsmen (age = 23.2 yr, Ht = 189.6 cm, Wt = 85.3 kg, VO₂max = 5.2 1 / min or 61.6 ml / kg min⁻¹) were tested in one pre-experimental procedure and three experimental treatments. The pre-experimental procedure involved the determination of VO₂max, and the loads at which 40 -, 50 -, and 60% VO₂max occurred from a progressive load VO₂max. The th
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Yalavac, Irem. "Assessing the scope of reductive cyclisations of lactones using SmI2-H2O." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/assessing-the-scope-of-reductive-cyclisations-of-lactones-using-smi2h2o(7a7988bd-609c-4ab2-b541-6106bb7a3fb7).html.

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This report firstly describes the 5-exo-dig,6-exo-trig cascade cyclisation of 6-membered allenyl lactones for the formation of highly decorated 7,6-fused bicycles using the SmI2-H2O reducing system. Preliminary studies showed that 5-exo-dig,5-exo-trig cascade reactions successfully yield 7,5-fused bicycles. However, performance of 6-exo-trig reactions of this type with SmI2 has little literature precedent and was not known to proceed with SmI2 in combination with H2O.In order to investigate the cascade cyclisations, cis and trans allenyl lactones with alkene or alkyne chains tethered at the 2-
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Hateley, Martin John. "Studies in the dehydrogenase catalysed reduction of 2-ketocarboxylic acids." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299531.

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SAKELLARIOU, FARGUES REINE. "Reactivite chimique et photochimique d'alpha -enones dans les milieux organises." Toulouse 3, 1986. http://www.theses.fr/1986TOU30044.

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Dans une premiere partie on determine les zones monophasiques des diagrammes des phases pseudoternaires de plusieurs microemulsions. Dans l'une d'elles l'isophorone remplace l'huile. Ensuite les chapitres ii et iii sont consacres aux reactions de photocycloaddition (a+a, a+b) d'alpha -enones (isophorone, coumarine, dimethylthymine). On montre que les phenomenes observes sont lies aux differentes localisations possibles des substrats, aux mecanismes de reaction et aux structures des milieux. En conclusion, la localisation des reactifs a l'interface permet la combinaison des effets de concentrat
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Duffy, Lorna A. "From spirocyclisations to ring-size selective reductions : the effect of co-solvent on the chemistry of SMI₂." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496693.

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Nlooto, Manimbulu. "Effect of stavudine dosage reduction on the incidence of symptomatic hyperlactataemia/lactic acidosis in adults female HIV/AIDS infected patients treated at Dr George Mukhari Hospital." Thesis, University of Limpopo (Medunsa Campus), 2010. http://hdl.handle.net/10386/216.

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Theses (Msc.(Med.)(Pharmacy))--University of Limpopo, 2010.<br>With the availability of Highly Active Antiretroviral Therapy (HAART), one of the limitations of treatment safety is the occurrence of adverse events associated with antiretroviral agents. The aim of this study was to establish whether stavudine dosage reduction prevents toxicity from developing and minimizes the incidence of symptomatic hyperlactataemia/lactic acidosis (LA) in adults female HIV/AIDS infected patients. This retrospective study covered adult patients treated at the adult ARV clinic, Dr George Mukhari Hospital
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Books on the topic "Lactone reduction"

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Neligan, Patrick J., and Clifford S. Deutschman. Pathophysiology and causes of metabolic acidosis in the critically ill. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0255.

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Critical illness is typically characterized by changes in the balance of water and electrolytes in the extracellular space, resulting in the accumulation of anionic compounds that manifests as metabolic acidosis. Metabolic acidosis manifests with tachypnoea, tachycardia, vasodilatation, headache and a variety of other non-specific symptoms and signs. It is caused by a reduction in the strong ion difference (SID) or an increase in weak acid concentration (albumin or phosphate). Increased SID results from hyperchloraemia, haemodilution or accumulation of metabolic by-products. A reduction in SID
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Book chapters on the topic "Lactone reduction"

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Ito, Katsuji, Tsutomu Katsuki, Paul Mather, and John Whittall. "Oxidation of Ketones to Lactones or Enones." In Regio- and Stereo- Controlled Oxidations and Reductions. John Wiley & Sons, Ltd, 2007. http://dx.doi.org/10.1002/9780470090244.ch7.

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Azerad, Robert, Didier Buisson, Sophie Maillot, and Jamal Ouazzani-Chahdi. "The Microbiological Reduction/Oxidation Concept: An Approach to a Chemoenzymatic Preparation of Optically Pure Lactones and Lactonic Synthons." In Bioorganic Chemistry in Healthcare and Technology. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4684-1354-0_20.

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Taber, Douglass. "Enantioselective Synthesis of Lactones and Cyclic Ethers." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0045.

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Developments in organocatalysis have turned toward the enantioselective construction of lactones. Shi-Wei Luo and Liu-Zhu Gong of the University of Science and Technology of China have found (J. Org. Chem. 2007, 71, 9905) that catalyzed addition of acetone to an α-hydroxy acid 1 proceeded with high ee. Esterification of the addition product followed by reduction and acid work-up delivered the lactone 4 with high dr and ee. In a complementary approach, Jean-Marc Vincent and Yannick Landais of the University Bourdeaux-1 showed (Chem. Commun. 2007, 4782) that catalyzed condensation of an aldehyde with an α-hydroxy acid 5 delivered the tetronic acid 8 in high ee. It may be that 8 could also be reduced with useful selectivity. Cong-Gui Zhao of the University of Texas, San Antonio has devised conditions (Organic Lett. 2007, 9, 2745) for the condensation of the keto phosphonates such as 10 with aldehydes to give, after oxidation, the δ-lactone 12. Carbohydrates such as glucose 13 are inexpensive, molecularly-complex starting materials. Subhash Chandra Taneja of the Indian Institute of Integrative Medicine, Jammu Tawi, has found conditions (J. Org. Chem. 2007, 72, 8965) for the single-step I2 -catalyzed transformation of 13 to 14, in which each of the alcohols have been differentiated. In a complementary approach described (Tetrahedron Lett. 2007, 48, 6389) by Tushar Kanti Chakraborty of the Indian Institute of Chemical Technology, Hyderabad, Ti-mediated reduction of 15 was shown to be highly diastereoselective, setting the two new stereogenic centers (marked by*) in 16. Building on work by Mead, Daniel Romo of Texas A&amp;M has shown (J. Org. Chem. 2007, 72, 9053) that reductive cyclization of 18 also proceeded with high diastereocontrol, to give 19. As illustrated by the conversion of 20 to 21 reported (Tetrahedron Lett. 2007, 48, 7351) by Zsuzsa Juhász and László Somsák of the University of Debrecen, six-membered ring cyclic ethers can also be formed from carbohydrate precursors. Richard E. Taylor of the University of Notre Dame has taken advantage (Angew. Chem. Int. Ed. 2007, 46, 6874) of the “chemical chameleon” nature of a sulfone, using it both the stablilize the anion for intramolecular alkylation, to form 23, and as a leaving group, leading to 24.
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Taber, Douglass. "The Smith Synthesis of ( + )-Lyconadin A." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0086.

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The pentacyclic alkaloid ( + )-lyconadin A 3, isolated from the club moss Lycopodium complanatum, showed modest in vitro cytotoxicity. A key step in the first reported (J. Am. Chem. Soc. 2007, 129, 4148) total synthesis of 3, by Amos B. Smith III of the University of Pennsylvania, was the cyclization of 1 to 2. The pentacyclic alkaloid (+)-lyconadin A 3, isolated from the club moss Lycopodium complanatum, showed modest in vitro cytotoxicity. A key step in the first reported (J. Am. Chem. Soc. 2007, 129, 4148) total synthesis of 3, by Amos B. Smith III of the University of Pennsylvania, was the cyclization of 1 to 2. The pentacyclic skeleton of 3 was constructed around a central organizing piperidine ring 9. This was prepared from the known (and commercial) enantiomerically-pure lactone 4. The akylated stereogenic center of 9 was assembled by diastereoselective hydroxy methylation of the acyl oxazolidinone 5 with s-trioxane, followed by protection. Reduction of the imide to the alcohol led to the mesylate 7, which on reduction of the azide spontaneously cyclized to give, after protection, the piperidine 8. Selective desilylation of the primary alcohol then enabled the preparation of 9. The plan was to assemble the first carbocyclic ring of 3 by intramolecular aldol condensation of the keto aldehyde 15. The enantiomerically-pure secondary methyl substituent of 15 derived from the commercial monoester 10. Activation as the acid fluoride followed by selective reduction led to the volatile lactone 11. Opening of the lactone with H3CONHCH3HCl gave, after protection, the Weinreb amide 12. Alkylation of the derived hydrazone 13, selectively on the methyl group, led, after deprotection, to 15. The intramolecular aldol condensation of 15 did deliver the unstable cyclohexenone 1. Under the acidic conditions of the aldol condensation, the enol derived from the piperidone added in a Michael sense, from the axial direction on the newly-formed ring, to give the trans-fused bicyclic diketone 2.
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Taber, Douglass. "The Rychnovsky Synthesis of Leucascandrolide A." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0087.

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The macrolactone leucascandrolide A 4, isolated from the calcareous sponge L. caveolata, has both cytotoxic and antifungal activity. The key step in the synthesis of 4 reported (J. Org. Chem. 2007, 72, 5784) by Scott D. Rychnovsky of the University of California, Irvine, was the stereoselective condensation of the aldehyde 1 with the allyl vinyl ether 2 to give 3. The cyclic ether of 1 was assembled from the crotyl addition product 5. Tandem Ru-catalyzed metathesis/hydrogenation converted 5 to the lactone 6. Reduction of 6 to the lactol followed by activation as the acetate gave 7, axial-selective condensation of which with the enol ether 8 delivered the enone 9. Diastereoselective Itsuno-Corey reduction of 9 followed by protecting group exchange and oxidation then gave 1, containing four of the eight stereogenic centers of leucascandrolide A 4. The vinyl ether 2 was readily prepared from the corresponding homoallylic alcohol. Condensation of 1 with 2 involved Lewis acid activation of the aldehyde, addition of the resulting carbocation to the vinyl ether, and cyclization with trapping by bromide ion. In this process, the other four of the eight stereogenic centers were assembled. Three of those centers were formed in the course of the reaction. While stereocontrol was not perfect, the route is pleasingly succinct, so practical quantities of diastereomerically pure 3 could be prepared. To complete the synthesis, the secondary alcohol of 3 was methylated. Selective desilyation of the primary alcohol followed by oxidation and desilylation then set the stage for the Mitsunobu macrolactonization. The intermediates in the Mitsunobu reaction are such that the lactonization can proceed with either inversion of absolute configuration at the secondary center, or retention. While the usually-employed Ph3P gave the lactone with retention of absolute configuration, Bu3P led to clean inversion. The last challenge was the establishment of the (Z) alkene of the side chain. This was accomplished using the Toru protocol. Coupling of the secondary bromide with the Cs salt 12 proceeded with inversion of absolute configuration, to give 13.
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Taber, Douglass F. "The Ma Synthesis of (-)-GB 13." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0098.

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An investigation of the activity of the Galbulimima alkaloids, exemplified by (-)- GB 13, led to the development of a series of potent thrombin receptor antagonists. Dawei Ma of the Shanghai Institute of Organic Chemistry devised (Angew. Chem. Int. Ed. 2010, 49, 5887) a concise route to 3 based on the coupling of the chirons 1 and 2. The starting point for the preparation of 1 was the unsaturated ester 4. Cyclization using the chiral enamine protocol developed by d’Angelo delivered the keto ester 6. Reduction with NaBH4 proceeded with substantial diastereocontrol to give an intermediate alcohol, which cyclized under acidic conditions to the lactone 1. The preparation of 2 began with dihydroresorcinol 7. Condensation with the enantiomerically pure amine 8 gave the enamine, that was converted to the bromide and cyclized to 9. Hydrogenation with substantial facial control set the ring fusion. Oxidation with 2-iodoxybenzoic acid (IBX) in DMSO introduced unsaturation with high regioselectivity, to give 2. The ketene silyl acetal 10 derived from the lactone 1 added under Mukaiyama conditions across the open face of 2, to give the adduct 11. The same IBX oxidation protocol was used to introduce unsaturation, and the product was equilibrated to give 12. Hydrogenation, again across the open face of the bicyclic enone, set the last stereogenic center of 13. To construct the cyclohexenone 15, it was necessary to oxidize the diol 14 to the keto aldehyde. Others had found that the Swern modification of the Pfitzner-Moffatt oxidation worked well in such cases, minimizing competing lactone formation. Even more useful was the Boger protocol, which returned to the original Pfitzner-Moffatt conditions, activating DMSO with TFAA. Use of DBU in place of the more typical Et3 N then cleanly delivered the aldol product, which was dehydrated and deprotected to give the enone 15. The final ring closure was effected by reduction of the enone with SmI2. The initially formed 16 was partially reduced to the diol under the reaction conditions, necessitating reoxidation with the Dess-Martin reagent. The introduction of unsaturation with the Nicolaou IBX protocol was again successful, even in this more complex and fragile system.
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Taber, Douglass. "Best Synthetic Methods: Oxidation and Reduction." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0003.

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Although methods both for reduction and for oxidation are well developed, there is always room for improvement. While ketones are usually reduced using metal hydrides, hydrogen gas is much less expensive on scale. Charles P. Casey of the University of Wisconsin has devised (J. Am. Chem. Soc. 2007, 129, 5816) an Fe-based catalyst that effects the transformation of 1 to 2. Note that the usually very reactive monosubstituted alkene is not reduced and does not migrate. Takeshi Oriyama of Ibaraki University has developed a catalyst, also Fe-based (Chemistry Lett. 2007, 38) for reducing aldehydes to ethers. Using this approach, an alcohol such as 3 can be converted into a variety of substituted benzyl ethers, including 5. Simple aliphatic aldehydes and alcohols also work well. Oxidation of alcohols to aldehydes or ketones is one of the most common of organic transformations. Several new processes catalytic in metal have been put forward. Tharmalingam Punniyamurthy of the Indian Institute of Technology, Guwahati has found (Adv. Synth. Cat. 2007, 349, 846) that catalytic V(IV) oxide on silica gel, stirred with t-butyl hydroperoxide in t-butyl alcohol at room temperature smoothly oxidized 6 to 7. After the reaction, the catalyst was separated by filtration. Another carbonyl can also serve as the hydride acceptor, but then the transfer can be reversible. Jonathan M. J. Williams of the University of Bath has shown (Tetrahedron Lett. 2007, 48, 3639) that with a Ru catalyst, methyl levulinate 9 could serve as the hydride acceptor, with the byproduct alcohol being drained off as the lactone 11. Hansjörg Grützmacher of the ETH Zürich developed an Ir catalyst (Angew. Chem. Int. Ed. 2007, 46, 3567) with benzoquinone as the net oxidant. that showed marked preference for the oxidation of primary over secondary alcohols. Yasuhiro Uozumi of the Institute for Molecular Science, Aichi, has devised (Angew. Chem. Int. Ed . 2007, 46, 704) a nanoencapsulated Pt catalyst that worked well with O2 or even with air. The catalyst was easily separated from the product, and maintained its activity over several cycles.
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Taber, Douglass F. "The Reisman Synthesis of (–)-Maoecrystal Z." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0087.

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(–)-Maoecrystal Z 3 was isolated as a minor constituent from the Chinese medicinal herb Isodon eriocalyx. The synthesis of 3 reported (J. Am. Chem. Soc. 2011, 133, 14964) by Sarah E. Reisman of the California Institute of Technology, featuring as a key step the cyclization of 1 to 2, is a tribute to the power of one-electron reduction for carbon–carbon bond construction. The synthesis began with a Myers alkylation to prepare 6. The amide was reduced to the alcohol with the convenient ammonia–borane complex, and the alcohol was carried on to the iodide 7. The first carbocyclic ring of 3 was prepared by classic chemistry, the condensation of dimethyl malonate 9 with mesityl oxide 8, followed by selective removal of one of the ketone carbonyls. A salt-free Wittig reaction followed by hydrolysis, resolution, and reduction then completed the synthesis of 12. Exposure of 12 to peracid led to the epoxide 13 as an inconsequential mixture of diastereomers. The one-electron Nugent/RajanBabu/Gansäuer protocol was low yielding with methyl acrylate, but dramatically improved when the trifluoroethyl acrylate 14 was used as the acceptor. The lactone 15 was formed as a single diastereomer. Alkylation of 15 with 7 followed by oxidation gave 16, which was deprotected and oxidized to give 1. The cascade cyclization of 1 presumably proceeded by initial one-electron reduction of the more accessible aldehyde. The cyclization of the resulting radical onto the alkene may have been assisted by complexation of the lactone carbonyl with the required second equivalent of SmI2. The Sm enolate so prepared was then added to the second aldehyde to give 2. This cyclization sets one quaternary and three ternary stereogenic centers. Attempted monoprotection of 2 was not successful, so the bis acetate was prepared and ozonized, and the aldehyde was condensed with Eschenmoser’s salt to give 17. Careful monohydrolysis then completed the synthesis of (–)-maoecrystal Z 3
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9

Taber, Douglass F. "The Fukuyama Synthesis of (−)-Lepenine." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0094.

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The denudatine alkaloids, exemplified by (−)-lepenine 3, have been converted chem­ically into the physiologically-active aconitine alkaloids. Tohru Fukuyama of Nagoya University envisioned (J. Am. Chem. Soc. 2014, 136, 6598) an intramolecular Mannich condensation, the conversion of 1 to 2, that in a single step would assemble two of the six rings of 3. The starting material for the synthesis was the ether 4, prepared by Mitsunobu cou­pling of the phenol with L-lactic acid methyl ester. Reduction of the ester to the alde­hyde followed by the addition of vinylmagnesium chloride led to the secondary allylic alcohol. Claisen rearrangement with triethyl orthoacetate delivered not the ether, but rather 5, the desired product of an additional Claisen rearrangement. The phenol of 5 was protected as the mesylate, that was then subjected to ozonolysis with a reduc­tive workup to give the primary alcohol. This was protected as the pivalate, which was selectively saponified. The resulting carboxylic acid was cyclized to 6 using trifluoro­acetic anhydride. The triene 7 was prepared from 6 by the addition of vinylmagnesium chloride fol­lowed by dehydration. Prospective intramolecular Diels–Alder cycloadditions that would form five-or six-membered ring lactones often fail. In the event, the cycliza­tion of 7 to the seven-membered ring lactone 8 proceeded smoothly. The tetracyclic 8 could be brought to high ee by recrystallization. Hydroboration followed by reduc­tion then delivered the diol aldehyde 9, that was converted to 1 by reductive amina­tion followed by protection and oxidation. On deprotection, 1 cyclized to the iminium salt 10. Intramolecular Mannich addi­tion of the enol form of the ketone then proceeded, to give 2. It is possible to protect tertiary amines, inter alia by formation of the adduct with a borane. In this case, transient protection as the hydrochloride was sufficient to allow oxidation of the alcohol derived from 2 to the diene 11. This was reactive enough to undergo the Diels–Alder addition of ethylene, from the more open face, leading to 12. The now-extraneous methoxy groups were then removed reductively to give 13, and the last stereogenic center of 3 was installed by hydroboration of the alkene. Methylenation of 14 followed by Luche reduction then completed the synthesis of (−)-lepenine 3.
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10

Taber, Douglass F. "The Carreira Synthesis of (–)-Dendrobine." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0098.

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The tetracyclic alkaloid (–)-dendrobine 3 has at its core a cyclohexane that is substituted at each of its six positions, including one quaternary center. Erick M. Carreira of ETH Zürich chose (Angew. Chem. Int. Ed. 2012, 51, 3436) to assemble this ring by the Ireland-Claisen rearrangement of the lactone 1. The absolute configuration of the final product stemmed from the commercial enantiomerically pure acetonide 4, which was selectively converted to the Z-ester 5. Following the precedent of Costa, TBAF-mediated conjugate addition of 2-nitropropane to 5 proceeded with high diastereocontrol, to give, after free radical reduction, the ester 6, which was carried on the aldehyde 7. Exposure of the alkyne 9 to an in situ-generated Schwartz reagent followed by iodination gave 10 with 10:1 regioselectivity. It was possible to separate 10 from its regioisomer by careful silica gel chromatography. Metalation followed by the addition to 7 gave an intermediate that was conveniently debenzoylated with excess ethyl magnesium bromide to deliver the diol 11. Selective oxidation led to the lactone 1. Exposure of 1 to LDA and TMS-Cl induced rearrangement to the cyclohexene acid, which was esterified to give 2. Deprotection and oxidation then gave the enone 12. Cyclohexene construction by tethered Claisen rearrangement is a powerful transformation that has been little used in target-directed synthesis. Selective addition of pyrrolidine to the aldehyde of 12 generated an enamine, leading to an intramolecular Michael addition to the enone. This selectively gave the cis ring fusion, as expected, but the product was a mixture of epimers at the other newly formed stereogenic center. This difficulty was overcome by forming the enamine from N-methylbenzylamine. After cyclization, hydrogenation set the additional center with the expected clean stereocontrol, and also effected debenzylation to give 14. To close the last ring, the ketone 14 was brominated with the reagent 15, which was developed (Can. J. Chem. 1969, 47, 706) for the kinetic bromination of ketones. Exposure of the crude α-bromo ketone to 4-dimethylaminopyridine then effected cyclization to 16. Following the literature precedent, reduction of the ketone of 16 with NaBH4 followed by gentle warming led to (–)-dendrobine 3.
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Conference papers on the topic "Lactone reduction"

1

Murphy, S. "STORAGE OF PLATELETS FOR TRANSFUSION - CURRENT METHODS AND PROBLEMS TO BE SOLVED." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643999.

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In the 1970's, when platelet concentrates (PC) were stored in "first generation" plastic containers at 22°C, many showed a fall in pH.In vivo viability was well maintained as pH fell from the starting level, 7.1, to 6.2 but was progressively lost below thatlevel. pH after a storage interval correlated with the platelet count in the PC, the higher the count, the lower the pH after storage. Since 30-50% of PC might have pH below 6.2 after 3 days of storage, shelflife was severely limited.We now have "second generation" containers which allow storage for 7 days without significant fall in pH.Supe
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2

Terres, W., W. Kupper, C. Hamm, and W. Bleifeld. "RESTING MYOCARDIAL ISCHEMIA AFTER INTRAVENOUS INFUSION OF BM 13.177, A THROMBOXANE RECEPTOR ANTAGONIST." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643466.

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We conducted a double blind placebo controlled trial of BM 13.177, a thromboxane receptor antagonist, given intravenously in patients (PTS) with stenoses &gt;70 % of the left anterior descending coronary artery and stable exertional angina pectoris (AP). The study had to be stopped after enrollment of 8 PTS, because 2 had developed resting AP after initiation of the study medication. Both proved to belong to the 4 PTS who had received BM 13.177 (12.5 mg/min). While in one PT, AP was mild, transient and associated with only slight decreases in coronary sinus blood flow (CSBF) and myocardial lac
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