- Evaluation of the key aroma compounds in beef and pork vegetable gravies a la chef by stable isotope dilution assays and aroma recombination experiments
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Although the aroma compounds of meat processed as such have been studied previously, data on complete homemade dishes containing beef and pork meat were scarcely studied. Recently, 38 odor-active compounds were characterized in beef and pork vegetable gravies using GC-olfactometry. In the present investigation, the most odor-active compounds were quantitated in a freshly prepared stewed beef vegetable gravy (BVG) as well as a stewed pork vegetable gravy (PVG) by means of stable isotope dilution assays. Calculation of odor activity values (OAVs; ratio of concentration to odor threshold) revealed 3-mercapto-2- methylpentan-1-ol, (E,E)-2,4-decadienal, (E,Z)-2,6-nonadienal, (E)-2-decenal, (E)-2-undecanal, and 3-hydroxy-4,5-dimethyl-2(5H)-furanone as the most potent odorants in both gravies. However, significantly different OAVs were found for 12-methyltridecanal, which was much higher in the BVG, whereas (E,Z)-2,4-decadienal showed a clearly higher OAV in the PVG. Aroma recombination experiments performed on the basis of the actual concentrations of the odorants in both gravies revealed a good similarity of the aromas of both model mixtures containing all odorants with OAVs > 1 with those of the original gravies.
- Christlbauer, Monika,Schieberle, Peter
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Read Online
- Enantioselective Synthesis and Antifungal Activity of C18 Polyacetylenes
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Fungal pathogens cause serious crop diseases and decrease crop yields and quality. Polyacetylene alcohols are plant secondary metabolites and bioactive against various pathogenic fungi. They are, however, difficult to synthesize. In the present study, an efficient and highly enantioselective method (>98% ee) was established and employed to achieve the synthesis of the natural C18 polyacetylenes (S,E)-octadeca-1,9-dien-4,6-diyn-3-ol 1, (3R,10R,E)-octadeca-1,8-dien-4,6-diyne-3,10-diol 2, and their analogs. The title compounds were structurally characterized and biologically evaluated for fungicidal activities. The compounds exhibited high potencies against eight pathogenic fungal species tested, such as Colletotrichum gloeosporioiles, Bipolaris sorokiniana, Fusarium graminearum, and Fusarium pseudograminearum, with half-maximum effective concentrations ranging from 8 to 425 μg/mL, being similar to those of the fungicide thiophanate-methyl (3-408 μg/mL). These compounds are potential natural fungicides and fungicide lead candidates for further structural and property improvements.
- Ding, Shengli,Feng, Jiayang,Li, Changkai,Li, Honglian,Li, Qing X.,Liu, Jia,Lu, Shichao,Na, Risong,Pei, Yiming,Wang, Wenliang,Zhang, Meng
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Read Online
- Catalytic asymmetric synthesis of Japonilure and its enantiomer
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A mild, concise, and highly enantioselective (93% ee) synthesis of Japonilure and its enantiomer, Anomala osakana pheromone, is described. The key steps involve the asymmetric addition of methyl propionate to undec-2-ynal with a Zn-ProPhenol catalyst and the selective and partial reduction of the diynol ester to the cis-enol ester with Brown's P2-Ni catalyst, providing the first synthesis of the enol ester via semi-hydrogenating diynol ester.
- Xu, Hao,Li, Shuo-Ning,Yang, Yan-Qing,Zhou, Yun,Yang, Qian-Zhen,Bian, Qing-Hua,Zhong, Jiang-Chun,Wang, Min
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Read Online
- Enantioselective synthesis method of chiral (6Z, 9Z)-3, 4-epoxy octadecadiene
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The invention relates to the technical field of tea geometrid prevention and treatment, in particular to an enantioselective synthesis method of chiral (6Z, 9Z)-3, 4-epoxy octadecadiene. When the intermediate (2Z, 5Z)-octadiene-1-alcohol is used as a raw
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Paragraph 0048-0050; 0063-0065; 0078-0080
(2021/04/03)
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- Regioselective Iron-Catalysed Cross-Coupling Reaction of Aryl Propargylic Bromides and Aryl Grignard Reagents
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An iron-catalysed Kumada-type cross-coupling reaction between aryl substituted propargylic bromides and arylmagnesium reagents has been developed. Propargylic coupling products were the main or only outcome, and propargyl/allene regioselectivity was shown to depend on the electronic nature of the substituents on the triple bond of the substrate and on the arylmagnesium halide. Best selectivities were observed when electron donating substituents were present in either reagent. The process is stereoespecific, occurs with configuration inversion and no carbon-based radicals seem to be involved in the mechanism. (Figure presented.).
- Manjón-Mata, Inés,Quirós, M. Teresa,Bu?uel, Elena,Cárdenas, Diego J.
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supporting information
p. 146 - 151
(2019/12/11)
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- Stereoselective synthesis of C3–C17 and C18–C34 subunits of bullatanocin utilizing α-chloro sulfide intermediates
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A convergent synthesis of bullatanocin is envisaged by the union of C18–C34, C3–C17 and the butenolide subunits. The synthesis of the C3–C17 and C18–C34 subunits is disclosed that takes advantage of the chirality of tartaric acid for 1,2-asymmetric induct
- Chowhan, L. Raju,Raghavan, Sadagopan
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supporting information
(2019/09/17)
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- Synthesis method of (3Z,6Z)-9,10-epoxy-octadecadiene
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The invention discloses a synthesis method of (3Z,6Z)-9,10-epoxy-octadecadiene which is one of tea geometrid sex pheromone components. The synthesis method comprises the following steps: coupling propynyl alcohol with bromooctane to produce undec-2-yn-1-ol, and catalytically hydrogenating the undec-2-yn-1-ol to obtain cis-undec-2-en-1-ol; performing a reaction on the cis-undec-2-en-1-ol and m-chloroperoxybenzoic acid to obtain undec-2,3-epoxy-1-ol; sulfonylating hydroxyl groups of the undec-2,3-epoxy-1-ol by p-methylsufonyl chloride to obtain p-methylsulfonyl ester; performing ring opening onan epoxidized compound under the conditions of tri-tert-butylphosphine and chlorosuccinimide to obtain 3-chloro-2-hydroxyundecyl methanesulfonate, and then performing ring closure under an alkali condition to obtain 3-chloro-1,2-epoxyundecane; then, performing ring opening under the conditions of n-butyl lithium and boron trifluorideetherate, and performing ring closure under the condition of potassium carbonate to obtain 2-octyl-3-(prop-2-yn-1-yl)oxirane; then, obtaining 2-(octane-2,5-diyn-1-yl)-3-octyloxirane under the condition of an iodo coupling reagent; and finally, performing hydrogenation catalysis to obtain a final product. The synthesis method is relatively low in cost, and is suitable for scale preparation.
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Paragraph 0036; 0037-0039
(2019/02/26)
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- Direct Access to Allenylphosphine Oxides via a Metal Free Coupling of Propargylic Substrates with P(O)H Compounds
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A direct and convenient approach for the coupling of propargylic substrates with diphenylphosphine oxide in the presence of Tf2O and 2,6-lutidine has been developed. The method provides a general approach for the construction of attractive allenylphosphoryl skeletons with high atom and step economy under metal free conditions.
- Yang, Chun-Hua,Fan, Huihui,Li, Huimin,Hou, Shenyin,Sun, Xiangkun,Luo, Donghao,Zhang, Yinchao,Yang, Zhantao,Chang, Junbiao
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supporting information
p. 9438 - 9441
(2019/11/20)
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- Synthetic method of highly-activity chiral acetylenic alcohol (S,E)-1,9-diene-4,6-diacetyl-3-octadecyl alcohol
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The invention discloses a synthetic method of highly-activity chiral acetylenic alcohol (S,E)-1,9-diene-4,6-diacetyl-3-octadecyl alcohol. The synthetic method disclosed by the invention comprises thefollowing steps: bromooctane is taken as a starting raw material and is reacted in a reasonable proportion to synthesize required alkynol; and the efficient synthesis of active molecule (S,E)-1,9-diene-4,6-diyne-3-octadecanol is realized through reduction, bromination, coupling reactions, desilication and docking with a chiral molecule. According to the method, the yield in the reaction process ishigh, a synthetic route is simple, the raw material is simple and easy to obtain, the synthetic cost is low, reaction conditions are mild, the separation and purification operations are simple, and ahigh-purity target compound can be directly obtained; a chiral center is introduced in the last step, so that the possibility of racemization of the substance in the reaction is avoided; and in addition, the synthesized active molecule (S,E)-1,9-diene-4,6-diyne-3-octadecanol has a wide application prospect.
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Paragraph 0015; 0025-0027
(2018/09/13)
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- Iron-Catalyzed Coupling of Propargyl Bromides and Alkyl Grignard Reagents
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An iron-catalyzed Kumada-type cross-coupling reaction of propargyl halides with alkylmagnesium reagents is described. The reaction is fast, takes place in smooth conditions, tolerates several functional groups that would be able to react with the Grignard reagent, and may afford either allene or propargyl coupling derivatives. Factors involved in the observed regioselectivity have been studied.
- Domingo-Legarda, Pablo,Soler-Yanes, Rita,Quirós-López, M. Teresa,Bu?uel, Elena,Cárdenas, Diego J.
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supporting information
p. 4900 - 4904
(2018/09/10)
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- Highly regioselective gold-catalyzed formal hydration of propargylic: Gem -difluorides
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Herein, we report a highly regioselective gold-catalyzed formal hydration of propargylic gem-difluorides. Not only does this transformation provide access to versatile fluorinated building blocks that were difficult or hardly possible to access beforehand, but it also represents a rare case of a highly regioselective gold-catalyzed hydroalkoxylation of internal alkynes and puts forward the utility of the difluoromethylene unit as a directing group in catalysis.
- Hamel, Jean-Denys,Hayashi, Tatsuru,Cloutier, Mélissa,Savoie, Paul R.,Thibeault, Olivier,Beaudoin, Meggan,Paquin, Jean-Fran?ois
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supporting information
p. 9830 - 9836
(2017/12/08)
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- Hydrogen-Bond-Promoted Friedel-Crafts Reaction of Secondary Propargylic Fluorides: Preparation of 1-Alkyl-1-aryl-2-alkynes
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We report that aromatic propargylation is achievable with secondary propargylic fluorides, thus affording 1-alkyl-1-aryl-2-alkynes. In the present case, hydrogen bonding is responsible for the activation of the C-F bond. A large excess of arene nucleophil
- Hamel, Jean-Denys,Beaudoin, Meggan,Cloutier, Mélissa,Paquin, Jean-Fran?ois
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supporting information
p. 2823 - 2828
(2017/12/15)
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- The (+)-cis- and (+)-trans-Olibanic Acids: Key Odorants of Frankincense
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Frankincense (olibanum) is one of the oldest aromatic materials used by humans, but the key molecular constituents contributing to its characteristic odor remained unknown. Reported herein is the discovery that (1S,2S)-(+)-trans- and (1S,2R)-(+)-cis-2-octylcyclopropyl-1-carboxylic acids are highly potent and substantive odorants occurring in ppm amounts in all of the frankincense samples analyzed, even those showing radically different volatile compositions. These cyclopropyl-derived acids provide the very characteristic old churchlike endnote of the frankincense odor.
- Cerutti-Delasalle, Céline,Mehiri, Mohamed,Cagliero, Cecilia,Rubiolo, Patrizia,Bicchi, Carlo,Meierhenrich, Uwe J.,Baldovini, Nicolas
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supporting information
p. 13719 - 13723
(2016/10/26)
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- Enantioselective Rhodium-Catalyzed Atom-Economical Macrolactonization
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A highly attractive route toward macrolactones, which form the cyclic scaffold of a multitude of diverse natural compounds, is described. Although many chemical approaches to this structural motif have been explored, an asymmetric variant of the cyclization is unprecedented. Herein we present an enantioselective macrolactonization through an intramolecular atom-economical rhodium-catalyzed coupling of ω-allenyl-substituted carboxylic acids. The use of a modified diop ligand, chiral DTBM-diop, led to high enantioselectivity (up to 93 % ee). The reaction tolerated a large variety of functionalities, including α,β-unsaturated carboxylic acids and depsipeptides, and provided the desired macrocycles with very high enantio- and diastereoselectivity.
- Ganss, Stephanie,Breit, Bernhard
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supporting information
p. 9738 - 9742
(2016/08/10)
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- Tetris in monolayers: Patterned self-assembly using side chain shape
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The "kinked" shapes of conjugated alkadiynes constrain chain packing in monolayers on HOPG. Centrally located diyne units permit assembly of 1,5-bis(alkadiyne)anthracene monolayers. Off-center diynes inhibit self-assembly. Shape matched pairs of off-center diyne chains direct self-assembly of compositionally patterned, two component monolayers.
- Xue, Yi,Zimmt, Matthew B.
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supporting information; experimental part
p. 8832 - 8834
(2011/09/16)
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- HETEROCYCLIC DERIVATIVES THAT ARE USED IN THE TREATMENT OF NEURODEGENERATIVE DISEASES
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The present invention relates to compounds of Formula (I) below, to their pharmaceutically acceptable salts and to their isomers or mixtures of isomers: HetAr—X—CHR1R2 (I) in which: -HetAr represents a group chosen from: —X represents a linear, saturated or unsaturated, hydrocarbon-based chain comprising from 8 to 22 carbon atoms, optionally interrupted by an —NH— or —NH—CO— group, —R1 represents a hydrogen atom or an —OH, —O(C1-C6)alkyl, —OCO((C1-C6)alkyl), —OSO2((C1-C6)alkyl) or —OSO3H group, and —R2 represents a hydrogen atom or a (C2-C6)alkynyl, (C2-C6)alkenyl or (C3-C6)cycloalkyl group. The present invention also relates to a process for preparing the compounds of Formula (I), and also to the use thereof, especially in the treatment of neurodegenerative diseases.
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Page/Page column 14
(2011/06/10)
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- Structure-Activity relationship of aliphatic compounds for nematicidal activity against pine wood nematode (Bursaphelenchus xylophilus)
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Nematicidal activity of aliphatic compounds was tested to determine a structure-activity relationship. There was a significant difference in nematicidal activity among functional groups. In a test with alkanols and 2E-alkenols, compounds with C8-C11 chain length showed 100% nematicidal activity against pine wood nematode, Bursaphelenchus xylophilus, at 0.5 mg/mL concentration. C6-C10 2E-alkenals exhibited >95% nematicidal activity, but the other compounds with C 11-C14 chain length showed weak activity. Nematicidal activity of alkyl acetates with C7-C11 chain length was strong. Compounds belonging to hydrocarbons, alkanals, and alkanoic acetates showed weak activity at 0.5 mg/mL concentration. Nematicidal activity of active compounds was determined at lower concentrations. At 0.25 mg/mL concentration, whole compounds except C8 alkanol, C8 2E-alkenol, and C7 alkanoic acid showed >80% nematicidal activity. C 9-C11 alkanols, C10-C11 2E-alkenols, C8-C9 2E-alkenals, and C9-C10 alkanoic acids showed >80% nematicidal activity at 0.125 mg/mL concentration. Only C11 alkanol exhibited strong nematicidal activity at 0.0625 mg/mL concentration, the lowest concentration that was tested. 2010 American Chemical Society.
- Seo, Seon-M.I.,Junheon, Kim,Eunae, Kim,Park, Hye-M.I.,Kim, Young-Joon,Park, I.L.-Kwon
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experimental part
p. 1823 - 1827
(2010/09/09)
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- Total synthesis of clathculins A and B
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Clathculins A and B represent a new class of vic-diamine alkaloids containing a PA2 unit as the basic structure. We report the first total syntheses of 1 and 2, which confirm the assigned structure of each. Dependence of their NMR spectroscopic behavior a
- Hoye, Rebecca C.,Anderson, Gretchen L.,Brown, Susan G.,Schultz, Erica E.
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supporting information; experimental part
p. 7400 - 7403
(2011/02/22)
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- Enantioselective synthesis of Anomala osakana pheromone and Janus integer pheromone: A flexible approach to chiral γ-butyrolactones
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The enantioselective synthesis of Anomala osakana pheromone and Janus integer pheromone has been achieved without using any protecting groups. The synthesis involved using an asymmetric alkynylation to obtain γ-hydroxy-α,β-acetylenic esters with high ee (84%) and yields (~80%), followed by selective hydrogenation and lactonization in high overall yields (87% and 89%).
- Lin, Li,Zhao, Qiangyang,Li, A-Ni,Ren, Fengbo,Yang, Fanzhi,Wang, Rui
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supporting information; experimental part
p. 3663 - 3665
(2009/10/23)
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- An improved synthesis route to functionalized 2-alkyn-1-ylboronates: Useful intermediates for the preparation of α-allenic alcohols
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Functionalized 2-alkyn-1-ylboronates were successfully prepared in good yields by reacting various acyclic and cyclic (iodomethyl)boronates with various alkynyllithium salts. Amongst various (iodomethyl)boronates studied, 2-(iodomethyl)-1,3,2-dioxa-4,4,5,5-tetramethylborolane provided improved chemical yields of 2-alkyn-1-ylboronates with pyran- and triisopropylsilyl- substituted alkynyllithium salts. 2-Alkyn-1-ylboronate bearing an acid sensitive structure (pyran) was successfully synthesized which would be very difficult to achieve under previously reported reaction conditions. The exceptionally rapid rearrangement of the "ate" complex derived from the pinacol (iodomethyl)boronate, suppression of the side product formation, and the stability of the pinacol 2-alkyn-1-ylboronate are some of the notable merits of this protocol. This new procedure offers a simple and convenient alternative route to the existing methodologies, in terms of the milder reaction conditions, functional group compatibility, and the ease of the operation. The synthesis scope of this class of 2-alkyn-1-ylboronates was demonstrated by reacting the pinacol 2-alkyn-1-ylboronate with benzaldehyde, which yielded the α-allenic alcohol in good yield and regioselectivity.
- Roy, Chandra D.,Soundararajan, Raman,Brown, Herbert C.
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experimental part
p. 241 - 249
(2009/05/27)
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- A new method for the preparation of 1,5-diynes. Synthesis of (4E,6Z,10Z)-4,6,10-hexadecatrien-1-ol, the pheromone component of the cocoa pod borer moth Conopomorpha cramerella
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(Figure Presented) A new method for the synthesis of 1,5-diynes, from the reaction of 1,3-dilithiopropyne and propargyl chlorides, was developed. This new methodology was used to prepare (4E,6Z,10Z)-4,6,10-hexadecatrien-1-ol, one of the pheromone componen
- Pereira, Alban R.,Cabezas, Jorge A.
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p. 2594 - 2597
(2007/10/03)
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- Preparation and cancer cell invasion inhibitory effects of C16-alkynic fatty acids.
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Five C(16)-alkynic fatty acids (2-6) were prepared and examined their inhibitory effects on cancer cell invasion. It has been found that hexadeca-6,8,10-triynoic acid (5) and hexadeca-8,10,12-triynoic acid (6) exhibit similar potent inhibitory activities with that of octadeca-8,10,12-triynoic acid (1) which was isolated from Scurrula atropurpurea (Loranthaceae).
- Ohashi, Kazuyoshi,Winarno, Hendig,Mukai, Mutsuko,Shibuya, Hirotaka
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p. 463 - 466
(2007/10/03)
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- Study of the regioselectivity in the hydrotelluration of hydroxy alkynes
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Vinylic tellurides were synthesized by the addition of organotellurols to acetylenic alcohols and the regioselectivity of the reaction was evaluated.
- Stefani, Hélio A.,Cardoso, Lincoln D. G.,Valduga, Claudéte J.,Zeni, Gilson
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p. 167 - 172
(2007/10/03)
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- Stereospecific synthesis of (E,Z)- and (Z,Z)-hexadeca-10,12-dienal. Sex pheromone components of Diaphania hyalinata
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Isomeric (E,Z)- and (Z,Z)-hexadeca-10,12-dienal were prepared, stereospecifically, in 51% and 43% overall yields from dec-1-yne.
- Cabezas, Jorge A.,Oehlschlager, Allan C.
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p. 107 - 111
(2007/10/03)
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- A simple, convenient, general procedure for the synthesis of 2-alkyn-1-ylboronates.
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Representative 2-alkyn-1-ylboronates have been synthesized in good to excellent yields using the reaction of the newly available diisopropyl iodomethylboronate with alkynyllithiums generated in situ. Comparable yields are obtained from both acyclic and cyclic boronates. However, 2-(iodomethyl)-1,3,2-dioxa-4,4,5-tetramethylborolane gave superior yields with a wide variety of alkynyllithiums. This procedure offers a simple and convenient alternative route to existing methodologies in terms of the milder reaction condition and the ease of the operation.
- Brown, Herbert C.,Roy, Chandra Deo,Soundararajan, Raman
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p. 765 - 768
(2007/10/03)
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- (Carboxyalkyl)benzyl propargyl ethers as selective inhibitors of leukocyte-type 12-lipoxygenases
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A series of (carboxyalkyl)benzyl propargyl ethers was synthesized and tested as inhibitors of 12-lipoxygenase (12-LO) from porcine leukocyte cytosol. Optimum activity was displayed by 3-[4-[(2- tridecynyloxy)methyl]phenyl]propanoic acid. Altering the length of the alkyl side chain attached to the acetylenic group reduced activity. Changing the substitution pattern in the (carboxyalkyl)benzyl group from para to meta or ortho also reduced activity. Analogs in which the triple bond was replaced by a double bond or an allene displayed reduced activity, whereas fully saturated analogs were inactive. High concentrations (10 μM) of the most potent acetylenic (carboxylalkyl)benzyl ethers did not inhibit human platelet 12-LO, human neutrophil 5-LO, rabbit reticulocyte 15-LO, or soybean 15-LO. Thus, this class of compounds represents the first example of isoform specific LO inhibitors.
- Gorins, Gilles,Kuhnert, Lethea,Johnson, Carl R.,Marnett, Lawrence J.
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p. 4871 - 4878
(2007/10/03)
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- A new stereocontrolled, pyrylium-based route to conjugated dienynes: The first synthesis of Carduusyne A
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A new stereocontrolled route to conjugated dienynes is described, utilising organometallic addition to pyrylium salts followed by Wittig homologation and dehydrohalogenation. The utility of this methodology is illustrated in the first total synthesis of the marine metabolite Carduusyne A.
- Charoenying, Patchanee,Huw Davies,McKerrecher, Darren,Taylor, Richard J. K.
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p. 1913 - 1916
(2007/10/03)
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- Stereoselective Synthesis of Perfluoroalkylated (E,E)-Dienes from Perfluoroalkylated Alkynes. The Synthesis of Fluorinated Analogs of Lepidoptera Pheromones
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Pd(dba)2 -HOAc catalyzed the isomerization of 1-perfluoroalkyl-1-alkynes to give 1-perfluoroalkyl-(1E,3E)-dienes in good yield and stereoselectivity; the fluorinated analogs of Lepidoptera species sex pheromone attractants were synthesized applying this method.
- Wang, Zhong,Lu, Xiyan
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p. 11765 - 11774
(2007/10/02)
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- ARYL ALIPHATIC ACIDS
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Novel aryl aliphatic acids or derivatives thereof of the general formula R-(Cx-Cy)-(CmH2m)-G-C(R1)2-Ar-(CnH2n)-COOR2 are described which exhibit inhibiting activity against 12-lipoxygenase. The compounds are characterized by having a low level of toxicity. Also included are salts and esters of the aliphatic acids
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- Synthesis of α-acetylenic aldehydes from 2-acetylenic phenyl sulfides
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Monochlorination at the 1 position, with sulfuryl chloride, followed by hydrolysis converted 2-acetylenic phenyl sulfides into 2-acetylenic aldehydes.
- Fortes,Garrote
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p. 2869 - 2877
(2007/10/02)
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- REDUCTION DE DERIVES D'ALCOOLS PROPARGYLIQUES CATALYSEE PAR UN COMPLEXE DE PALLADIUM ZEROVALENT
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Catalysis by tetrakis(triphenylphosphine)palladium of the reaction of hydride donnors with secondary propargylic bromides, mesylates and phosphates increases markedly the amount of allene produced.The best results in that direction are obtained with mesylates and phosphates by using lithium triethylborohydride.The reaction then occurs with an ANTI introduction of the hydride with respect to the leaving group.A mechanism is proposed which explains the influence of the various parameters of the reaction.
- Colas, Yann,Cazes, Bernard,Gore, Jacques
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p. 165 - 173
(2007/10/02)
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- Synthesis of the optical antipodes of 4-alkyl-γ-lactones
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Optical antipodes of 4-alkyl-γ-lactones 3 have been prepared by photochemical rearrangement of optically active α,β-epoxy diazomethyl ketones 1 in ethanol to give 4-hydroxy-alkenoates 2, followed by reduction of the alkene bond and subsequent lactonization.The required epoxy diazomethyl ketones 1 were obtained via the following sequence of reactions: alkylation of 2-propyn-1-ol, subsequent reduction to the alkenols 6, Sharpless epoxidation to 2,3-epoxy alcohols 7, oxidation to glycidic esters 8 and finally conversion to diazo ketones 1.The enantiomeric purities range from 84 to 100percent.
- Thijs, Lambertus,Waanders, Peter P.,Stokkingreef, Edwin H. M.,Zwanenburg, Binne
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p. 332 - 337
(2007/10/02)
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- Synthesis of Heptadeca-1,8Z-diene
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Wittig reaction of methylenetriphenylphosphorane on 5-tetrahydropyranyloxypentanal (II) yields 6-tetrahydropyranyloxyhex-1-ene (III) which produces the alcohol IV on treatment with PTS/methanol.The latter (IV) undergoes smooth conversion into the corresponding bromide (V) on reaction with PBr3/pyridine.Alkylation of propargyl alcohol with n-octyl bromide in the presence of Li/liq.NH3 affords undec-2-yn-1-ol (VI) which on reduction in the presence of Lindlar's catalyst gives undec-2Z-en-1-ol (VII).Reaction of MsCl/TEA on VII in anhyd.CH2Cl2 forms the mesylate (VIII) which on coupling with V provides the title compound (I).
- Vig, O. P.,Sharma, M. L.,Kumari, Sarla,Rani, Veena
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p. 771 - 772
(2007/10/02)
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