cas 29171-20-8, 3,7-dimethyloct-6-en-1-yn-3-ol

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Quantitation of (R)- and (S)-Linalool in Beer Using Solid Phase Microextraction (SPME) in Combination with a Stable Isotope Dilution Assay (SIDA)
A stable isotope dilution assay (SIDA) was developed for the quantitation of both linalool enantiomers using synthesized [2H 2]R/S-linalool as the internal standard. For enrichment of the target compound from beer, a solid phase microextraction method (SPME) was developed. In comparison to the more time-consuming extraction/distillation cleanup of the beer samples, the results obtained by SPME/SIDA were very similar, even under nonequilibration conditions. Analysis of five different types of beer showed significant differences in the linalool concentrations, which were clearly correlated with the intensity of the hoppy aroma note as evaluated by a sensory panel. In addition, significant differences in the R/S ratios were measured in the beers. The SPME/SIDA yielded exact data independently from headspace sampling parameters, such as exposure time or ionic strength of the solution.
Steinhaus, Martin,Fritsch, Helge T.,Schieberle, Peter
p. 7100 - 7105
(2003)
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Bridgehead Modifications of Englerin A Reduce TRPC4 Activity and Intravenous Toxicity but not Cell Growth Inhibition
Modifications at the bridgehead position of englerin A were made to explore the effects of variation at this site on the molecule for biological activity, as judged by the NCI 60 screen, in which englerin A is highly potent and selective for renal cancer cells. Replacement of the isopropyl group by other, larger substituents yielded compounds which displayed excellent selectivity and potency comparable to the natural product. Selected compounds were also evaluated for their effect on the ion channel TRPC4 as well as for intravenous toxicity in mice, and these had lower potency in both assays compared to englerin A.
Wu, Zhenhua,Suppo, Jean-Simon,Tumova, Sarka,Strope, Jonathan,Bravo, Fernando,Moy, Melody,Weinstein, Ethan S.,Peer, Cody J.,Figg, William D.,Chain, William J.,Echavarren, Antonio M.,Beech, David J.,Beutler, John A.
supporting information
p. 1711 - 1716
(2020/10/19)

Acetylene method (by machine translation)
In the presence of a catalyst alkoxide or an amino N,N - salt, the saturated or unsaturated ketone or aldehyde compound is subjected to acetylene hydrogenation to obtain the corresponding alkynol compound, and has the advantages of moderate reaction rate, mild reaction, easy control, easy separation of the product, recyclable solvent and the like. (by machine translation)
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Paragraph 0040-0053; 0060-0068

(2019/11/29)

ENGLERIN DERIVATIVES FOR TREATMENT OF CANCER
Disclosed is a compound of formula (I) in which a, R1- R5 and X1 are as described herein. Also disclosed are a pharmaceutical composition containing the compound and a method of using the compound for treating cancer, such as renal cancer.
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Paragraph 0095; 0099

(2019/01/21)

Method for efficiently preparing alkynol
The invention relates to a method for efficiently preparing alkynol, belongs to the field of preparation of chemical intermediates and chemicals, and particularly relates to a preparation method of alkynol. The preparation method comprises the following steps that 1, alkali metal is added into an anhydrous alcohols solvent; an alcohol-alkali metal solution is prepared; 2, a compound I is added into the alcohol-alkali metal solution; uniform stirring is performed; cooling is performed to be 0 DEG C or below; 3, acetylene is introduced through being metered at normal pressure; alkynol is obtained; 4, the alkynol solution after reaction is neutralized by ammonium chloride and a same alcohol mixed suspension system; 5, the neutralized mixed suspension system is filtered; after alcohols are recovered from filter liquid, reduced pressure distillation is performed to obtain an alkynol product. The method overcomes the defect that under the existing harsh reaction conditions of high pressure,liquid ammonia and the like, the solid potassium hydroxide feeding difficulty is avoided; under the ordinary pressure condition, the ketone compounds are converted into alkynol at high conversion rate. The method has the advantages of high conversion rate, simple process and good product purity.
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Paragraph 0036; 0037; 0038; 0043; 0044; 0045; 0046

(2018/12/14)

α,β-Unsaturated Gold(I) Carbenes by Tandem Cyclization and 1,5-Alkoxy Migration of 1,6-Enynes: Mechanisms and Applications
1,6-Enynes bearing OR groups at the propargyl position generate α,β-unsaturated gold(I)-carbenes/ gold(I) stabilized allyl cations that can be trapped by alkenes to form cyclopropanes or 1,3-diketones to give products of α-alkylation. The best migrating group is p-nitrophenyl ether, which leads to the corresponding products without racemization. Thus, an improved formal synthesis of (+)-schisanwilsonene A has been accomplished. The different competitive reaction pathways have been delineated computationally.
Calleja, Pilar,Pablo, óscar,Ranieri, Beatrice,Gaydou, Morgane,Pitaval, Anthony,Moreno, María,Raducan, Mihai,Echavarren, Antonio M.
supporting information
p. 13613 - 13618
(2016/09/13)

Synthesis and Biological Evaluation of New (-)-Englerin Analogues
We report the synthesis and biological evaluation of a series of (-)-englerin A analogues obtained along our previously reported synthetic route based on a stereoselective gold(I) cycloaddition process. This synthetic route is a convenient platform to access analogues with broad structural diversity and has led us to the discovery of unprecedented and easier-to-synthesize derivatives with an unsaturation in the cyclopentyl ring between C4 and C5. We also introduce novel analogues in which the original isopropyl motif has been substituted with cyclohexyl, phenyl, and cyclopropyl moieties. The high selectivity and growth-inhibitory activity shown by these new derivatives in renal cancer cell lines opens new ways toward the final goal of finding effective drugs for the treatment of renal cell carcinoma (RCC).
López-Suárez, Laura,Riesgo, Lorena,Bravo, Fernando,Ransom, Tanya T.,Beutler, John A.,Echavarren, Antonio M.
p. 1003 - 1007
(2016/05/24)

EPOXYAZULENE DERIVATIVES USEFUL FOR TREATING CANCER AND DIABETES
Disclosed is a compound of formula (I) in which R1-R5 and X1 are as described herein. Also provided are methods of using a compound of formula (I), including a method of treating cancer and a method of treating diabetes.
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Paragraph 0071; 0079

(2016/10/31)

Intramolecular hydroalkoxylation catalyzed inside a self-assembled cavity of an enzyme-like host structure
Self-assembled resorcin[4]arene hexamer catalyzes the intramolecular hydroalkoxylation of unsaturated alcohols to the corresponding cyclic ethers under mild conditions. The mode of catalysis and encapsulation-based substrate selectivity of the host efficiently mimic the basic principle of operation observed in enzymes.
Catti,Tiefenbacher
supporting information
p. 892 - 894
(2015/02/05)

COMBINATIONS OF HEPATITIS C VIRUS INHIBITORS
The present disclosure is generally directed to antiviral compounds, and more specifically directed to combinations of compounds which can inhibit the function of the NS5A protein encoded by Hepatitis C virus (HCV), compositions comprising such combinations, and methods for inhibiting the function of the NS5A protein.
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Page/Page column 612

(2015/02/02)

Facile Alder-Ene Reactions of Silylallenes Involving an Allenic C(sp2)-H Bond
Facile and selective Alder-ene reactions of silylallenes involving the activation of an allenic C(sp2)-H over an allylic C(sp3)-H bond is described. In this ene reaction, the presence of a silyl substituent was found to be critical for the observed reactivity and selectivity since the corresponding alkyl-substituted allenes show different reaction profiles. Computational studies show that the origin of this unusual reactivity is the lower bond dissociation energy of the α-C(sp2)-H bond in silylallenes compared to the corresponding nonsilylated allenes.
Sabbasani, Venkata R.,Huang, Genping,Xia, Yuanzhi,Lee, Daesung
supporting information
p. 17210 - 17214
(2016/01/25)

Construction of 1,5-enynes by stereospecific Pd-catalyzed allyl-propargyl cross-couplings
The palladium-catalyzed cross-coupling of chiral propargyl acetates and allyl boronates delivers chiral 1,5-enynes with excellent levels of chirality transfer and can be applied across a broad range of substrates.
Ardolino, Michael J.,Morken, James P.
supporting information; scheme or table
p. 8770 - 8773
(2012/07/02)

Enantioselective synthesis of (-)-englerins A and B
Chemical Equation Present. All that glitters is gold: The total synthesis of the natural enantiomers of englerins A and B has been completed using a goldcatalyzed stereoselective domino alkyne/alkene/carbonyl cyclization of an enyne with an unprotected alcohol group at a stereogenic allylic position (see scheme; TES = triethylsilyl).
Molawi, Kian,Delpont, Nicolas,Echavarren, Antonio M.
supporting information; scheme or table
p. 3517 - 3519
(2010/08/06)

2-ALKOXYMETHYL-3-ISOALKENYL-1-METHYLCYCLOPENTENES, USE THEREOF, IN PARTICULAR AS FRAGRANCE SUBSTANCES, CORRESPONDING ARTICLES AND PRODUCTION METHODS
Compounds of formula (A) are described wherein, independently of one another, the following applies to groups R and R1: R is methyl or ethyl, and R1 is hydrogen or methyl, wherein the meandering line shows that for R1=methyl, the associated double bind is (E)- or (Z)-configured. Furthermore, methods for producing compounds of formula (A) and the use of corresponding compounds as fragrance and/or flavouring substances are described.
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Page/Page column 12

(2009/04/24)

A short and efficient synthetic strategy for the total syntheses of (S)-(+)- and (R)-(-)-Plakolide A
Concise and efficient total syntheses of anticancer agents (S)-(+)-Plakolide A and (R)-(-)-Plakolide A were accomplished in eight steps and an overall yield of 39 % starting from geraniol. The key steps in our strategy are Sharpless asymmetric epoxidation, double elimination, and Stille coupling reactions. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Mohapatra, Debendra K.,Pramanik, Chinmoy,Chorghade, Mukund S.,Gurjar, Mukund K.
p. 5059 - 5063
(2008/03/18)

Transport of ethyne in form of alpha-alkynols as ethyne precursors
The present invention relates to a new method for a safe transport of ethyne in form of α-alkynols as precursors for ethyne. The new method comprises three steps. In a first step the synthesis of the α-alkynol(s) is performed by reacting ethyne with (a) carbonyl compound(s). The second step comprises the transport of the resulting α-alkynol(s) in a safe manner, whereas the safety requirements for this transport are not as high as for ethyne because α-alkynol(s) are normally classified for transportation as hazardous class 3. In the third step the α-alkynol(s) can be cleaved and the ethyne and the carbonyl compound(s) can be obtained in the cleavage reaction and can be separated to yield pure products for further applications.
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Page/Page column 5

(2008/06/13)

Platinum- and gold-catalyzed rearrangement reactions of propargyl acetates: Total syntheses of (-)-α-cubebene, (-)-cubebol, sesquicarene and related terpenes
Propargyl acetates, in the presence of catalytic amounts of late transition-metal salts such as PtCl2 or AuCl3, represent synthetic equivalents of α-diazoketones. This notion is corroborated by a concise approach to various sesquiterpene natural products starting from readily available substrates. Specifically, (+)-carvomenthone (17) is converted into propargyl acetate (S)-26 by a sequence involving Stille cross-coupling of its kinetic enol triflate 18, regioselective hydroboration/oxidation of the resulting 1,3-diene 19, and addition of an alkynyl cerium reagent to aldehyde 21 thus obtained. Since the latter step was found to be unselective, the configuration of the reacting propargyl acetate was unambiguously set by oxidation followed by diastereoselective transfer hydrogenation by using Noyori's catalyst 25. Compound (5)-26, on treatment with PtCl2 in toluene, converted exclusively to the tricyclic enol acetate 27, which was sap onified to give norcubebone 11 in excellent overall yield. The conversion of this compound into the sesquiterpene alcohol (-)-cubebol (6) was best achieved with MeCeCl2 as the nucleophile, whereas the formation-of the parent hydrocarbon (-)-α-cubebene (4) was effected in excellent yield by recourse to iron-catalyzed cross coupling methodology developed in this laboratory. Since norketone 11 has previously been transformed into (-)-β-cubebene (5) as well as (-)-4-epicubebol 8, our approach constitutes formal total syntheses of these additional natural products as well. Along similar lines, the readily available propargyl acetates 1, 33 and 47 were shown to give access to 2-carene 44, sesquicarene 39, and episesquicarene 51 in excellent overall yields. In this series, however, the cy cloisomerization reaction was best achieved with catalytic amounts of AuCl3 in 1,2-dichloroethane as the solvent. In addition to these preparative results, our data provide some insight into the mechanism of these remarkable skeletal rearrangement reactions. Transformations of this type are likely triggered by initial coordination of the alkyne unit of the substrate to the carbophilic transition-metal cation. Formal attack of the alkene moiety onto the resulting π-complex engenders the formation of an electrophilic cyclopropyl carbene species which subsequently reacts with the adjacent acetate unit to give the final product. The alternative phasing of events, implying initial attack of the acetate (rather than the alkene moiety) onto the metal-alkyne complex, is inconsistent with the stereochemioal data obtained during this total synthesis campaign.
Fuerstner, Alois,Hannen, Peter
p. 3006 - 3019
(2008/02/04)

PtCl2-mediated cycloisomerization of unsaturated propargylic carboxylates
The PtCl2-mediated cycloisomerization of unsaturated propargylic carboxylates yields differently functionalized bicyclo[4.1.0]heptane enol esters from moderate to good yield, in a very diastereoselective manner. We have prepared and submitted to PtCl2-catalyzed cycloisomerization a series of differently substituted hept-1-en-6-ynes with different O-acyl (acetyl, trichloroacetyl, 3,4,5-trimethoxybenzoyl, etc.) protecting groups at propargylic positions, investigating also the effect of the geometry at the double bond, as well as the effect of the number of substituents at the alkene moiety. As a result, we have found that the O-acetyl migrating group is the best one in terms of simplicity and chemical yields. In this reaction we have isolated mixtures of compounds formed by minor 1-acetoxy-allenes and major bicyclo[4.1.0]heptane derivatives. Major products are the result of a sequential process involving steps of cycloisomerization plus cyclopropanation, followed by acyl migration. The basic methanolysis (K2CO3, MeOH) of these intermediates gave mixtures of cis and trans-caran-2-ones. This two-step protocol (cycloisomerization plus basic methanolysis) for the syntheses of α,β-unsaturated cyclopropyl ketones constitutes a synthetic alternative to the usual unfriendly, intramolecular cyclopropanation of unsaturated α-diazocarbonyl derivatives. The formation of these bicyclo[4.1.0]heptane derivatives is a simple, but efficient entry into the skeleton of the 'carane' family of natural products.
Anjum, Shazia,Marco-Contelles, José
p. 4793 - 4803
(2007/10/03)

Microwave-mediated claisen rearrangement followed by phenol oxidation: A simple route to naturally occurring 1,4-benzoquinones. The first syntheses of verapliquinones A and B and panicein A
The naturally occurring 1,4-benzoquinones 2-methoxy-6-propyl-1,4- benzoquinone (1), 2-methoxy-6-pentyl-1,4-benzoquinone (primin 2), 2-methoxy-6-pentadecyl-1,4-benzoquinone (3), 2-methoxy-6-heptadecyl-l,4- benzoquinone (dihydroirisquinone, pallasone B; 4) were synthesized by a simple protocol involving microwave accelerated Claisen rearrangement of allyl ethers 10, followed by hydrogenation of the side chain alkene, and oxidation to the quinone. The Claisen-based methodology was extended to the first synthesis of the marine benzoquinones verapliquinones A and B (5 and 6), and panicein A (7). Isoarnebifuranone (9) was also synthesized by a similar strategy.
Davis, Christopher J.,Hurst, Timothy E.,Jacob, Aouregan M.,Moody, Christopher J.
p. 4414 - 4422
(2007/10/03)

ETHYNYLATION PROCESS
A process for the manufacture of an acetylenically unsaturated alcohol comprising reacting formaldehyde, an aldehyde or a ketone (a carbonyl compound) with acetylene in the presence of ammonia and an alkali metal hydroxide, the molar ratio of the alkali metal hydroxide to the carbonyl compound being less than 1 : 200. The reaction products, which depending on the starting carbonyl compound are propargyl alcohol or 1-monosubstituted or 1,1-disubstituted derivatives thereof, are of use as intermediates in the synthesis of many useful end products, inter alia in the field of vitamins and carotenoids.
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Page 5-6

(2008/06/13)

Preparation of higher alpha, beta-unsaturated alcohols
Higher α,β-unsaturated alcohols are prepared by monoethynylation of a ketone by the NH3/KOH method, if desired hydrogenation of the acetylene alcohol in the presence of hydrogen over a Pd-containing thin layer catalyst, purifying distillation of the hydrogenation product, preferably in a dividing wall column with recirculation of the unreacted ketone to the ethynylation step, and, if desired, preparation of higher alcohols having in each case 5 more carbon atoms in the chain by reacting the alcohols prepared by monoethynylation and, if desired, partial hydrogenation with alkyl acetoacetatesor diketene in a Carroll reaction to form ketones and using these as starting materials for the steps ethynylation, optional hydrogenation and fractional distillation.
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(2008/06/13)

Mechanistic dichotomy in CpRu(CH3CN)3PF6 catalyzed enyne cycloisomerizations
Enynes are easily accessible building blocks as a result of the rich chemistry of alkynes and thus represent attractive substrates for ring formation, A ruthenium catalyst for cycloisomerization effects such reaction of 1,6- and 1,7-enynes typically at room temperature in acetone or DMF under neutral conditions. The reaction is effective for forming five- and six-membered rings of widely divergent structure. The alkyne may bear both election-donating and election-withdrawing substituents. The alkene may be di- or trisubstituted. Introduction of a quaternary center at the propargylic position of an ynoate, however, completely changes the nature of the reaction. In the case of a 1,6-enynoate, a seven-membered ring forms in excellent yield under equally mild conditions. Evidence is presented to indicate a complete change in mechanism. In the former case, the reaction involves the intermediacy of a ruthenacyclopentene. In the latter case, a C-H insertion to form a π-allylruthenium intermediate is proposed and supported by deuterium-labeling studies. A rationale is presented for the structural dependence of the mechanism.
Trost, Barry M.,Toste, F. Dean
p. 5025 - 5036
(2007/10/03)

A short synthesis of cordiachromene
Cordiachromene was synthesized from 5-methyl hept-5-en-2-one by using a Claisen rearrangement.
Kahn, Philippe H.,Cossy, Janine
p. 8113 - 8114
(2007/10/03)

Stereoselective synthesis of β-ketoesters from prop-2-yn-1-ols
The activation of allylic prop-2-yn-1-ols by the [Ru(μ-O2CH)(CO)2(PPh3)]2 catalyst in the presence of carboxylic acids leads to unsaturated β-ketoesters in one step. The utilization of optically active prop-2-yn-1-ols provides a new stereoselective access to optically active β-ketoesters with retention of configuration at the propargylic carbon.
Darcel, Christophe,Bruneau, Christian,Dixneuf, Pierre H.,Roberts, Stanley M.
p. 9241 - 9252
(2007/10/03)

Base induced opening of 2,3-epoxychlorides: An efficient preparation of trans-chlorovlnyl alcohols
A highly efficient protocol for the sythesis of of chiral trans-1-chlorvinyl alcohols (2) from chiral 2,3-epoxychloride is described by using stoicheiometric amount of LiNH2 or LDA.
Yada,Deshpande, Prasad K.,Sharma
p. 4495 - 4496
(2007/10/02)

AN EFFECTIVE, PRACTICAL METHOD FOR THE SYNTHESIS OF CHIRAL PROPARGYL ALCOHOLS
The preparation of chiral propargyl alcohols (2) is described by LiNH2 or LDA induced double elimination of chiral epoxychlorides (4), derived from their corresponding epoxyalcohols (3) which are available easily by Sharpless asymmetric epoxidation of the primary allyl alcohols.Whereas, use of stoichiometric amount of base on 4 provides chirally enriched trans-1-chlorovinyl alcohols (14).
Yadav, J. S.,Deshpande, Prasad K.,Sharma, G. V. M.
p. 7033 - 7046
(2007/10/02)

Asymmetric Construction of Optically Active 3-Hydroxyalkyne Functionalities
An efficient method for the construction of optically active 3-hydroxyalkyne functionalities has been developed using optically active α,β-epoxy alcohols readily accessible from non-chiral allyl alcohol precursors.
Takano, Seiichi,Samuzi, Kiyohiro,Sugihara, Takumichi,Ogasawara, Kunio
p. 1344 - 1345
(2007/10/02)

Functionalization of terminal trisubstituted alkenes and derivatives thereof
The invention relates to a process for preparing compounds having the general structure: STR1 wherein R is hydrogen or an acyclic or alicyclic fragment containing between one and about ten carbon atoms, and R1 is hydrogen or an alkyl containing between one and about four carbon atoms or an aryl group.
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(2008/06/13)

SEMIHYDROGENATION OF ACETYLENES; MODIFIED LINDLAR CATALYST
The effect of doping Lindlar catalyst with different metal salts (shown in Table 1) on selectivity, during semihydrogenation of some acetylenes to the corresponding olefins, has been studied.Lindlar catalyst modified with MnCl2 has been found to be more selective and reproducible.
Rajaram, J.,Narula, A. P. S.,Chawla, H. P. S.,Dev, Sukh
p. 2315 - 2322
(2007/10/02)

Catalytic rearrangement
Process for converting secondary and tertiary acetylenic carbinols to the corresponding alpha,beta-unsaturated carbonyl compounds by rearranging the carbinol with (trilower alkyl-, tricycloalkyl-, triaryl- or triarylalkyl-siloxy)-vanadium oxide catalyst in the presence of a silanol where either the vanadium oxide or the silanol contains a phenyl group substituted with at least one electron withdrawing group.
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(2008/06/13)