- Synthetic study of an intermediate towards paracentrone
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Paracentrone (1), the second naturally occurring C31-methyl ketone apocarotenoid from fucoxanthin (2), was first isolated from the sea urchin Paracentrotus lividus. In this study, we focused on this carotenoid metabolite and report on a synthetic approach towards (3E)-(5R)-[(2R,4S)-2-hydroxy-4-(tert-butyldimethylsilyl)oxy-2,6,6-trimethylcyclohexylidene]-1-iodo-4-methyl-1,3, 5-hexatriene (5), a synthetic intermediate towards 1. This was obtained from epoxy acetylene (11) via (2E)-(4R)-[(2R,4S)-2-hydroxy-4-(tert-butyldimethyl-silyl)oxy-2,6,6-trimethylcyclohexylidene]-3-methylpenta-2,4-dien-1-ol (7).
- Kaneyama, Taiki,Fujimaru, Kazumi,Takemura, Mami,Hasegawa, Kizuku,Hamada, Masahiro,Kishimoto, Takao,Urabe, Daisuke,Nakajima, Noriyuki
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p. 281 - 294
(2019/08/01)
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- Discovery of a Potent Free Fatty Acid 1 Receptor Agonist with Low Lipophilicity, Low Polar Surface Area, and Robust in Vivo Efficacy
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The free fatty acid receptor 1 (FFA1 or GPR40) is established as an interesting potential target for treatment of type 2 diabetes. However, to obtain optimal ligands, it may be necessary to limit both lipophilicity and polar surface area, translating to a need for small compounds. We here describe the identification of 24, a potent FFA1 agonist with low lipophilicity and very high ligand efficiency that exhibit robust glucose lowering effect.
- Hansen, Steffen V. F.,Christiansen, Elisabeth,Urban, Christian,Hudson, Brian D.,Stocker, Claire J.,Due-Hansen, Maria E.,Wargent, Ed T.,Shimpukade, Bharat,Almeida, Reinaldo,Ejsing, Christer S.,Cawthorne, Michael A.,Kassack, Matthias U.,Milligan, Graeme,Ulven, Trond
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supporting information
p. 2841 - 2846
(2016/04/10)
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- A method of product yield allylol cis
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The invention relates to a method for improving the yield of an allyl alcohol maleinoid form product, the formula (1) are isomerized into a mixture of the formula (2) and the formula (3), the formula (1), the formula (2) and the formula (3) are selected from alkyl, aryl and alkaryl, R2 is selected from H, alkyl and aryl, in a solvent and with the existence of a heterogeeous acid catalyst, the formula (1) is subjected to reaction, the solvent is water or a multiphase solvent system which comprises an aqueous phase and an organic solvent phase, and the organic solvent phase comprises an organic solvent which is selected from ethers, ketone or saturated fat hydrocarbon or a mixture of the same and is unmixed with water, the formula (1) is subjected to allylic rearrangement reaction, and a certain proportion of formula (3) is added into the allylic rearrangement reaction system of the formula (1); the gaseous phase interior label content of the formula (3) is greater than 95%. According to the invention, the forming of the product maleinoid form (2) is facilitated, the proportion of the maleinoid form (2) to the transform (3) is enhanced, and the yield of the maleinoid form (2) can be improved by about 13% compared with an original system.
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Paragraph 0030-0032
(2017/03/17)
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- Synthesis of C6 acetylenic alcohols
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C6 acetylenic alcohols are important intermediates in the synthesis of Vitamin A and carotenoids. New synthesis methods of the C6 acetylenic alcohols and their four derivatives are reported. These designed synthesis methods are useful improvement to the present methodologies. Structures of these compounds are confirmed by 1H NMR, IR and mass spectra analysis.
- Pu, Shuai,Zhang, A.I. Gui,Zhang, Shao Feng,Wang, Y.U. Liang
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p. 635 - 638
(2015/02/18)
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- ORTHO-FLUORO SUBSTITUTED COMPOUNDS FOR THE TREATMENT OF METABOLIC DISEASES
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There is provided novel fluoro-substituted compounds capable of modulating the G- protein-coupled receptor GPR40, compositions comprising the compounds, and methods for their use for controlling insulin levels in vivo and for the treatment of conditions such as type II diabetes, hypertension, ketoacidosis, obesity, glucose intolerance, and hypercholesterolemia and related disorders associated with abnormally high or low plasma lipoprotein, triglyceride or glucose levels.
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Page/Page column 46-47
(2012/10/18)
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- Intramolecular pyridone/enyne photocycloaddition: Partitioning of the [4 + 4] and [2 + 2] pathways
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Chemical equations presented. Intramolecular photocycloaddition (>290 nm) between a 1,3-enyne and a 2-pyridone is far more selective than the intermolecular version; a three-atom linkage both controls regiochemistry and separates the [2 + 2] and [4 + 4] pathways. All four head-to-head, head-to-tail, tail-to-head, and tail-to-tail tetherings have been investigated. Linkage via the ene of the enyne leads to [2 + 2] products regardless of alkene geometry, whereas linkage through the yne results in [4 + 4] cycloadducts. The bridged 1,2,5-cyclooctatriene products of [4 + 4] cycloaddition are unstable and undergo a subsequent [2 + 2] dimerization reaction.
- Kulyk, Svitlana,Dougherty, William G.,Kassel, W. Scott,Zdilla, Michael J.,Sieburth, Scott M.
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supporting information; experimental part
p. 2180 - 2183
(2011/06/24)
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- PHOTOCHEMICAL ISOMERIZATION OF A PENT-2-EN-4-YN-1-OL
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The present invention relates to a process for photochemically isomerizing an E-pent-2-en-4-yn-1-ol to a Z-pent-2-en-4-yn-1-ol and vice versa.
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Page/Page column 7-8
(2009/07/25)
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- Process for the rearrangement of allyl alcohols
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The present invention is directed to a process for isomerizing a pent-1-en-3-ol according to formula (1) to a mixture of the stereoisomers Z-pent-2-en-1-ol (2) and E-pent-2-en-1-ol (3) according to formulae (2) and (3) wherein R1 is selected from alkyl, aryl, and alkylaryl radicals, R2 is selected from H, alkyl, and aryl radicals; which process comprises reacting the pent-1-en-3-ol (1) in a solvent and in the presence of a heterogeneous acid catalyst. The heterogeneous acid catalyst is preferably selected from the group consisting of Br?nsted acids on a carrier, strong acidic cation exchangers and polymers having acidic groups. The products of the process according to the present invention are important intermediates for the manufacture of isoprenoids such as vitamin A and derivatives thereof and carotenoids.
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Page/Page column 7
(2009/12/23)
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- PROCESS FOR ISOMERIZING A PENT-1-EN-3-OL
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The present invention relates to a process for isomerizing a pent-1-en-3-ol to a mixture of the isomers Z-pent-2-en-1-ol and E-pent-2-en-1-ol by reacting the pent-1-en-3-ol (1) in a multiphase system comprising an aqueous phase and an organic solvent phase, and in the presence of an acid catalyst which is not a cation exchanger, wherein the organic solvent phase comprises a water-immiscible organic solvent.
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Page/Page column 11
(2008/12/08)
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- Synthesis of pluraflavin A "aglycone"
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The "aglycone" of pluraflavin A (2) has been synthesized. The key features of this synthesis include a 1,3-dipolar cycloaddition between a nitrile oxide (cf. 14) and an olefin (22) to yield an isoxazoline followed by subsequent conversion into the γ-pyrone of pluraflavin A. The epoxide moiety linked to the pyrone is installed prior to Diels-Alder installation of the D ring, which allows access to a number of potentially active cytotoxic intermediates en route to the final compound. The preliminary in vitro results of two such compounds are also included with the racemic title compound exhibiting cytotoxicity in the nanomolar range.
- Wright, Benjamin J. D.,Hartung, John,Peng, Feng,Van De Water, Ryan,Liu, Haibo,Tan, Quen-Hui,Chou, Ting-Chao,Danishefsky, Samuel J.
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supporting information; experimental part
p. 16786 - 16790
(2009/04/14)
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- Isomerization of a pentol
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In a process for catalytically isomerizing Z-3-methylpent-2-en-4-yn-1-ol to E-3-methylpent-2-en-4-yn-1-ol in a mixture of both these stereoisomers there are employed as the isomerization catalyst bromine radicals and the isomerization is conducted in a two-phase system of an aqueous phase and the stereoisomeric mixture phase, the stereoisomeric mixture optionally being present in an essentially water-immiscible organic solvent, with intermixing of the reaction mixture and at temperatures from about -10°C to about 100°C. The source of the bromine radicals is generally an alkali metal or alkaline earth metal bromide, or ammonium bromide. In one embodiment of the process of the present invention a salt of a heavy metal is used as the catalyst for promoting the generation of bromine radicals from the source thereof, and in addition oxygen is generally used as an auxiliary agent for promoting the bromine radical generation. In a further embodiment there is used as such catalyst a strong peroxide-type oxidizing agent, e.g. an alkali metal or alkaline earth metal peroxomonosulphate, peroxoborate, peroxodisulphate or peroxodiphosphate, or the system hydrogen peroxide/alkali metal or alkaline earth metal sulphate. The stereoisomer produced and isolated in the larger proportion, i.e. Z-pentol, is a useful intermediate, e.g. for the manufacture of vitamin A, and the stereoisomer produced and isolated in the smaller proportion, i.e. E-pentol, is also a useful intermediate, in this case e.g. for the manufacture of astaxanthin, zeaxanthin and further carotenoids.
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- Synthetic studies toward potent cytotoxic agent amphidinolide B: Synthesis of the C8-C18 fragment
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A practical synthesis of the C8-C18 fragment 1 of amphidinolide B is described in which the Stille coupling method was employed to construct the trisubstituted C28=C13-C14=C15 's-cis-1,3-diene' moiety from suitably functionalized vinyl iodide (4) and vinyl stannane (5) fragments, the former being prepared from an acetylene precursor using Negishi's carboalumination/iodination method.
- Chakraborty,Thippeswamy
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p. 150 - 152
(2007/10/03)
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- A general and facile synthesis of substituted furans by palladium- catalyzed cycloisomerization of (Z)-2-en-4-yn-1-ols
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A general and facile synthesis of furans, based on Pd(II)-catalyzed cycloisomerization of (Z)-2-en-4-yn-1-ols, is described. Cycloisomerization reactions are carried out at 25-100 °C in the presence of a very simple catalytic system, consisting of K2PdI4, under essentially neutral conditions. This new methodology is very versatile and can be applied to the synthesis of a variety of substituted furans, including particularly fragile, naturally occurring furans such as rosefuran. Efficient synthetic approaches for the regioselective synthesis of suitably substituted (Z)-2-en-4-yn-1-ols have been developed.
- Gabriele,Salerno,Lauria
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p. 7687 - 7692
(2007/10/03)
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- Synthesis of a diterpene taxoid skeleton, bicyclo[9.3.1]pentadecatriene
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The synthesis of bicyclo[9.3.1]pentadecatriene skeleton was investigated by employing cyclization reactions using two key precursors bearing acetylene cobalt complex. Cyclization for the synthesis of strained twelve-membered ring was achieved via Nicholas type reaction in reasonable yield. Reductive decomplexation of the dicobalt hexacarbonyl moiety of the cyclization product was achieved with n-Bu3SnH in the presence of a catalytic amount of NBS in 1,4-cyclohexadiene solvent.
- Shibuya, Satoshi,Isobe, Minoru
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p. 6677 - 6698
(2007/10/03)
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- Versatile synthesis of bicyclo[9.3.1]pentadecatriene for new bicyclic taxoids
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A common carbon skeleton bicyclo[9.3.1]pentadecatriene of taxachitrienes was synthesized in its des-methyl form in short steps. The key step was Nicholas-Hosomi type reaction in the acidic cyclization between ene-yne biscobalthexacarbonyl complex electrophile with allyltrimethylsilane nucleophile. Decomplexation of the biscobalthexacarbonyl was achieved with a tin hydride and NBS in 1,4-cyclohexadiene solvent.
- Shibuya, Satoshi,Isobe, Minoru
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p. 373 - 374
(2007/10/03)
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