41143-12-8Relevant articles and documents
STUDIES ON THE SYNTHESIS OF GLOEOSPORONE - SYNTHESIS OF THE PROPOSED 2,8-DISUBSTITUED OXOCANE STRUCTURE
Carling, Robert W.,Holmes, Andrew B.
, p. 6133 - 6136 (1986)
Gloeosporone is neither the cis- nor the trans-2,8-disubstituted oxocane (1) nor its tautomer (2) whose total syntheses are described in this Letter.
Synthesis of Medium Ring Ethers. Part 3. Disproof of the Proposed 2,8-Disubstituted Oxocane Structure for Gloeosporone. Synthesis of pseudo-Gloeosporone
Carling, Robert W.,Clark, J. Stephen,Holmes, Andrew B.,Sartor, Dirk
, p. 95 - 102 (1992)
Synthesis of the cis- and trans-2,8-disubstituted oxocane derivatives 2 and 3 (carrying the unusual γ,δ-diketohexanecarboxylic acid side chain) by ozonolysis of the alkynes 14 and 18 (prepared respectively from the alcohols 11 and 15) demonstrated unequivolally that neither of these compounds nor their hydroxy-γ-lactone ring (lactol) tautomeres 1 correspond to the naturally occurring fungal self germination inhibitor gloeosporone.A study of 4,5-dioxohexanoic itself 9 revealed a remarkably low tendency to exist as its hydroxy-γ-lactone (lactol) tautomer 10.
Practical synthesis of hex-5-ynoic acid from cyclohexanone
Starostin,Lapitskaya,Ignatenko,Pivnitsky,Nikishin
, p. 81 - 84 (2000)
Hex-5-ynoic acid, a multipurpose synthon, was synthesized in three steps starting from cyclohexanone by bromination-dehydrobromination of the intermediate hex-5-enoic acid.
Enantioselective Lewis Acid Catalysis in Intramolecular [2 + 2] Photocycloaddition Reactions: A Mechanistic Comparison between Representative Coumarin and Enone Substrates
Brimioulle, Richard,Bauer, Andreas,Bach, Thorsten
, p. 5170 - 5176 (2015)
The intramolecular [2 + 2] photocycloaddition of three 4-(alk-4-enyl)coumarins and three 1-(alk-4-enoyl)-2,3-dihydropyridones was studied in the absence and in the presence of Lewis acids (irradiation wavelength = 366 nm). Spectral and kinetic data were collected for the respective parent compounds with a pent-4-enyl and a pent-4-enoyl chain. For the substrates with a methyl group in cis- or trans-position of the terminal alkene carbon atom (hex-4-enyl and hex-4-enoyl substitution), the stereochemical outcome of the [2 + 2] photocycloaddition was investigated. The mechanistic course of the uncatalyzed coumarin reactions was found to be a singlet pathway, whereas Lewis acid-catalyzed reactions proceeded with higher reaction rates in the triplet manifold. Contrary to that, the dihydropyridones underwent a fast triplet reaction in the absence of the Lewis acid. In the presence of a chiral Lewis acid the reactions slowed down but, due to the high extinction coefficient of the Lewis acid/dihydropyridone complexes at = 366 nm, still resulted in high enantioselectivity.
Atom-Economical Cross-Coupling of Internal and Terminal Alkynes to Access 1,3-Enynes
Liu, Mingyu,Tang, Tianhua,Apolinar, Omar,Matsuura, Rei,Busacca, Carl A.,Qu, Bo,Fandrick, Daniel R.,Zatolochnaya, Olga V.,Senanayake, Chris H.,Song, Jinhua J.,Engle, Keary M.
supporting information, p. 3881 - 3888 (2021/04/06)
Selective carbon-carbon (C-C) bond formation in chemical synthesis generally requires prefunctionalized building blocks. However, the requisite prefunctionalization steps undermine the overall efficiency of synthetic sequences that rely on such reactions, which is particularly problematic in large-scale applications, such as in the commercial production of pharmaceuticals. Herein, we describe a selective and catalytic method for synthesizing 1,3-enynes without prefunctionalized building blocks. In this transformation several classes of unactivated internal acceptor alkynes can be coupled with terminal donor alkynes to deliver 1,3-enynes in a highly regio- and stereoselective manner. The scope of compatible acceptor alkynes includes propargyl alcohols, (homo)propargyl amine derivatives, and (homo)propargyl carboxamides. This method is facilitated by a tailored P,N-ligand that enables regioselective addition and suppresses secondary E/Z-isomerization of the product. The reaction is scalable and can operate effectively with as low as 0.5 mol % catalyst loading. The products are versatile intermediates that can participate in various downstream transformations. We also present preliminary mechanistic experiments that are consistent with a redox-neutral Pd(II) catalytic cycle.
Cyclopropenones for Metabolic Targeting and Sequential Bioorthogonal Labeling
Row, R. David,Shih, Hui-Wen,Alexander, Austin T.,Mehl, Ryan A.,Prescher, Jennifer A.
, p. 7370 - 7375 (2017/06/05)
Cyclopropenones are attractive motifs for bioorthogonal chemistry, owing to their small size and unique modes of reactivity. Unfortunately, the fastest-reacting cyclopropenones are insufficiently stable for routine intracellular use. Here we report cyclop
Gold(I)-Catalysed Cyclisation of Alkynoic Acids: Towards an Efficient and Eco-Friendly Synthesis of γ-, δ- and ?-Lactones
Gasperini, Danila,Maggi, Lorenzo,Dupuy, Stéphanie,Veenboer, Richard M. P.,Cordes, David B.,Slawin, Alexandra M. Z.,Nolan, Steven P.
supporting information, p. 3857 - 3862 (2016/12/16)
The improved synthesis of γ-, δ- and ?-lactones using a dinuclear N-heterocyclic carbene (NHC)-gold(I) catalyst is reported. This solvent-free process provides access to γ- and δ-lactones in high regio- and stereoselectivity. Reactions were performed at l
Total synthesis and biological evaluation of amphidinolide v and analogues
Fuerstner, Alois,Fluegge, Susanne,Larionov, Oleg,Takahashi, Yohei,Kubota, Takaaki,Kobayashi, Junichi
experimental part, p. 4011 - 4029 (2009/12/24)
A sequence of ring-closing alkyne metathesis followed by an inter-molecular enyne metathesis of the resulting cyeloalkyne with ethene was used to forge the macrocyclic skeleton and to set the vicinal exo-methylene branches characteristic for the cytotox-ic marine natural product amphidino-lide V (1). Comparison of the synthetic material with an authentic sample of this extremely scarce metabolite isolated from a dinoflagellate of the Amphi- dinium sp. eliminated any doubts about its structure and allowed the absolute configuration of amphidinolide V to be determined as 8R,9S,10S,13R. Moreover, the flexibility inherent to the underlying synthesis blueprint also opened access to a comprehensive set of diastereomers of 1 as well as to synthetic analogues differing from the natural lead in the lipophilic chains appended to the macrocyclic core. This set of designed analogues gave first insights into structure-activity relationships, which revealed that the stereo-structure of the macrolactone is a highly critical parameter, whereas the examined alterations of the side chain did not diminish the cytotoxicity of the compounds to any notable extent.
Macrolides from the scent glands of the tropical butterflies Heliconius cydno and Heliconius pachinus
Schulz, Stefan,Yildizhan, Selma,Stritzke, Katja,Estrada, Catalina,Gilbert, Lawrence E.
, p. 3434 - 3441 (2008/09/19)
The four major components present in scent gland extracts of the male Costa Rica longwing butterflies Heliconius cydno and Heliconius pachinus were identified as 12- and 14-membered macrolides containing a C18-carbon skeleton. By use of micro-reactions and spectrometric examinations, structural proposals were made and subsequently proven by synthesis, using ring-closing-metathesis as the key steps. These macrolides, (9Z,11E,13S)- octadeca-9,11-dien-13-olide (5, S-coriolide), (9Z,11E,13S,15Z)-octadeca-9,11,15- trien-13-olide (6), (9Z,13S)-octadec-9-en-13-olide (13), and (9Z,11S)-octadec-9-en-11-olide (25), are biosynthetically obviously derived from oleic, linoleic, and linolenic acids. Their absolute configurations were determined by gas chromatographic investigations on chiral phases, showing all to possess (S)-configuration. The Royal Society of Chemistry.
Synthesis of alaremycin
Wang, Yong-Gang,Wachi, Masaaki,Kobayashi, Yuichi
, p. 481 - 483 (2007/10/03)
Methyl 5-azido-4-oxohexanoate was synthesized from 5-hexenoic acid in six steps and converted to the title compound by NaReO4- and CF 3SO3H-catalyzed reaction in Ac2CVCCl4 followed by hydrolysis of the methyl ester moiety. Georg Thieme Verlag Stuttgart.
