- Total synthesis of (+)-rubriflordilactone A
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Two enantioselective total syntheses of the nortriterpenoid natural product rubriflordilactone A are described, which use palladium- or cobalt-catalyzed cyclizations to form the CDE rings, and converge on a late-stage synthetic intermediate. These key processes are set up through the convergent coupling of a common diyne component with appropriate AB-ring aldehydes, a strategy that sets the stage for the synthetic exploration of other members of this family of natural products. Two in one: Two enantioselective total syntheses of the nortriterpenoid natural product rubriflordilactone A are described, which use palladium- or cobalt-catalyzed cyclizations to converge on a late-stage synthetic intermediate. These key processes are set up through the coupling of a common diyne component with appropriate AB-ring aldehydes, a strategy that enables a broad exploration of this family of natural products, as well as synthetic analogues.
- Goh, Shermin S.,Chaubet, Guilhem,Gockel, Birgit,Cordonnier, Marie-Caroline A.,Baars, Hannah,Phillips, Andrew W.,Anderson, Edward A.
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Read Online
- Synthesis of the polyketide moiety of the jamaicamides
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[Figure presented] Isolated from the Jamaican cyanobacterium Lyngbya majuscula, the jamaicamides are unique, mixed polyketide-peptides reported to be sodium channel blockers. The polyketide moiety contains an (E)-chloroolefin, an undetermined methyl stere
- Tanaka-Yanuma, Ayano,Watanabe, Satoshi,Ogawa, Keita,Watanabe, Sho,Aoki, Naoto,Ogura, Tetsuhiro,Usuki, Toyonobu
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Read Online
- Highly Regioselective 5-endo-tet Cyclization of 3,4-Epoxy Amines into 3-Hydroxypyrrolidines Catalyzed by La(OTf)3
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Highly regioselective intramolecular aminolysis of 3,4-epoxy amines has been achieved. Key features of this reaction are (1) chemoselective activation of epoxides in the presence of unprotected aliphatic amines in the same molecules by a La(OTf)3 catalyst and (2) excellent regioselectivity for anti-Baldwin 5-endo-tet cyclization. This reaction affords 3-hydroxy-2-alkylpyrrolidines stereospecifically in high yields. DFT calculations revealed that the regioselectivity might be attributed to distortion energies of epoxy amine substrates. The use of this reaction was demonstrated by the first enantioselective synthesis of an antispasmodic agent prifinium bromide.
- Hoshino, Yoshihiko,Iwabuchi, Yoshiharu,Kuriyama, Yuse,Sasano, Yusuke,Uesugi, Shun-ichiro,Yamaichi, Aoto
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supporting information
p. 1961 - 1965
(2021/01/04)
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- Regioselective Preparation of Fullerene Bis-adducts from Cleavable Macrocyclic Bis-malonates
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A series of macrocyclic bis-malonates incorporating either di-tert-butylsilylene or tetra-iso-propyldisiloxane subunits have been prepared and used for the regioselective bis-functionalization of [60]fullerene by double Bingel cyclopropanations. By system
- Trinh, Thi Minh Nguyet,Schillinger, Franck,Guerra, Sebastiano,Meichsner, Eric,Nierengarten, Iwona,Hahn, Uwe,Holler, Michel,Nierengarten, Jean-Fran?ois
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p. 3770 - 3786
(2021/06/27)
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- Modular Fragment Synthesis and Bioinformatic Analysis Propose a Revised Vancoresmycin Stereoconfiguration
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Elaborate fragments of the proposed stereostructure of the complex polyketide antibiotic vancoresmycin have been synthesized in a stereoselective fashion based on a modular and convergent approach. Significant nuclear magnetic resonance differences in one of these subunits compared with the natural product question the proposed stereoconfiguration. Consequently, an extensive bioinformatics analysis of the biosynthetic gene cluster was carried out, leading to a revised stereoconfigurational proposal for this highly potent antibiotic.
- Adamek, Martina,Essig, Sebastian,Kurz, Michael,Menche, Dirk,Sch?nenbroicher, Max,Seul, Maximilian,Spindler, Stefanie,Wingen, Lukas M.,Ziemert, Nadine
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supporting information
p. 1175 - 1180
(2021/01/13)
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- Diastereoselective and Branched-Aldehyde-Selective Tandem Hydroformylation-Hemiaminal Formation: Synthesis of Functionalized Piperidines and Amino Alcohols
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Starting from readily available allylglycine, a tandem hydroformylation-hemiaminal formation reaction has been developed for the synthesis of chiral functionalized piperidines, with very good diastereoselectivity and branched regioselectivity using Rh/(S,
- Pittaway, Rachael,Fuentes, José A.,Clarke, Matthew L.
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p. 2845 - 2848
(2017/06/07)
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- Fluorinated Musk Fragrances: The CF2Group as a Conformational Bias Influencing the Odour of Civetone and (R)-Muscone
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The difluoromethylene (CF2) group has a strong tendency to adopt corner over edge locations in aliphatic macrocycles. In this study, the CF2group has been introduced into musk relevant macrocyclic ketones. Nine civetone and five muscone analogues have been prepared by synthesis for structure and odour comparisons. X-ray studies indeed show that the CF2groups influence ring structure and they give some insight into the preferred ring conformations, triggering a musk odour as determined in a professional perfumery environment. The historical conformational model of Bersuker and co-workers for musk fragrance generally holds, and structures that become distorted from this consensus, by the particular placement of the CF2groups, lose their musk fragrance and become less pleasant.
- Callejo, Ricardo,Corr, Michael J.,Yang, Mingyan,Wang, Mingan,Cordes, David B.,Slawin, Alexandra M. Z.,O'Hagan, David
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p. 8137 - 8151
(2016/06/13)
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- Bisnucleophilic substitution as a synthetic tool for ready access to the piperidine alkaloids (+)-Connine, (+)-β-conhydrine, (+)-8-ethylnorlobelol, and (-)-halosaline
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Herein we report the stereoselective total synthesis of (+)-connine, (+)-β-conhydrine, (+)-8-ethylnorlobelol, and (-)-halosaline via bisnucleophilic substitution with benzylamine as the key step.
- Raju, Galla,Anitha, Kadimi,Krishna, Palakodety Radha
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p. 937 - 941
(2015/04/27)
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- Total Synthesis of Prostaglandin 15d-PGJ2 and Investigation of its Effect on the Secretion of IL-6 and IL-12
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An efficient synthesis of 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2, 1) is reported. The route described allows for diversification of the parent structure to prepare seven analogues of 1 in which the positioning of electrophilic sites is varied. These analogues were tested in SAR studies for their ability to reduce the secretion of proinflammatory cytokines. It was shown that the endocyclic enone is crucial for the bioactivity investigated and that the conjugated ω-side chain serves in a reinforcing manner.
- Egger, Julian,Fischer, Stefan,Bretscher, Peter,Freigang, Stefan,Kopf, Manfred,Carreira, Erick M.
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supporting information
p. 4340 - 4343
(2015/09/15)
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- SYNTHESIS OF DELTA 12-PGJ3 AND RELATED COMPOUNDS
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In one aspect, the present invention provides novel derivatives of Δ12-PGJ3 and modular synthetic pathways to obtaining Δ12-PGJ3 and derivatives thereof. In some aspects, the present derivatives of Δ12-PGJ3 are useful as chemotherapeutic agents. The present disclosure also describes compositions of these derivatives as well as methods of use of the derivatives thereof.
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Page/Page column 94; 95
(2015/04/15)
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- Fluorine in fragrances: Exploring the difluoromethylene (CF2) group as a conformational constraint in macrocyclic musk lactones
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The CF2 group is incorporated into specific positions within the lactone ring of the natural musk lactone, (12R)-(+)-12-methyl-13-tridecanolide, a constituent of Angelica root oil, Angelica archangelica L. The approach is taken as it was antici
- Corr, Michael J.,Cormanich, Rodrigo A.,Von Hahmann, Cortney N.,Bühl, Michael,Cordes, David B.,Slawin, Alexandra M. Z.,O'Hagan, David
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supporting information
p. 211 - 219
(2015/12/30)
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- Stereoselective Total Synthesis of psiAβ - A Sporogenic Psi Factor from Aspergillus nidulans 1
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The stereoselective total synthesis of psiAβ, a sporogenic psi factor of the fungus Aspergillus nidulans, has been accomplished starting from pentane-1,5-diol. The synthesis involves an enantioselective Keck allylation, an asymmetric alkynylzinc addition,
- Reddy, Parigi Raghavendar,Lingaiah, Maram,Das, Biswanath
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p. 975 - 976
(2014/05/06)
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- A very practical and selective method for PMB protection of alcohols
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A very simple, practical and efficient one-step heterogeneous protocol for the PMB protection of alcohols using Amberlyst-15 has been developed. The stability and hazard issues regarding PMBCl and PMBBr are totally avoided by directly using anisyl alcohol for the protection. Alcohols are protected in very good yields. The selective mono-PMB protection of diols as well as di-PMB protection of diols was achieved in good yields, along with the demonstration of recyclability of the catalyst.
- Chavan, Subhash P.,Harale, Kishor R.
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experimental part
p. 4683 - 4686
(2012/09/05)
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- Asymmetric total synthesis of 5′-epi-paecilomycin-F
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The asymmetric total synthesis of one of the stereoisomers of the naturally occurring 14-membered ring macrolide paecilomycin-F (5′-epi) has been reported in this article. The main highlight of the synthetic strategy involves the successful application of
- Jana, Nandan,Nanda, Samik
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experimental part
p. 802 - 808
(2012/09/07)
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- Palladium hydroxide catalyzed isomerization of primary allylic alcohols to aldehydes: Application to the formal synthesis of (-)-brevisamide
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The Pd-catalyzed isomerization of primary allylic alcohols into the corresponding saturated aldehydes has been achieved at room temperature for the first time in good to excellent yields under mild conditions. The functional group compatibility in this reaction is studied, and this new methodology has been successfully applied in the synthesis of a C5-C13 tetrahydropyran ring system of (-)-brevisamide in seven steps.
- Sabitha, Gowravaram,Nayak, Sambit,Bhikshapathi,Yadav
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supporting information; experimental part
p. 382 - 385
(2011/04/15)
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- A ring-closing metathesis (RCM)-based approach to mycolactonesa A/B
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The total synthesis of the mycobacterial toxins mycolactones A/B (1 a/b) has been accomplished based on a strategy built around the construction of the mycolactone core through ring-closing metathesis. By employing the Grubbs second-generation catalyst, t
- Gersbach, Philipp,Jantsch, Andrea,Feyen, Fabian,Scherr, Nicole,Dangy, Jean-Pierre,Pluschke, Gerd,Altmann, Karl-Heinz
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supporting information; experimental part
p. 13017 - 13031
(2012/01/02)
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- N-tert -Butanesulfinyl Imines in Alkaloid Synthesis: Stereoselective Synthesis of (R)-Coniine and Formal Synthesis of (S)-Coniceine 1
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A stereoselective synthesis of the hemlock alkaloid (R)-coniine and a formal synthesis of the indolizidine alkaloid (S)-δ-coniceine were achieved by means of a highly diastereoselective Barbier-type indium-mediated allylation strategy involving (S)-(N-ter
- Damodar, Kongara,Lingaiah, Maram,Bhunia, Nisith,Das, Biswanath
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experimental part
p. 2478 - 2482
(2011/09/16)
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- An asymmetric hydrogenation route to (-)-Spongidepsin
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Figure Presented. (-)-Spongidepsin 1, a cytotoxic marine natural product, was prepared via two iridium-catalyzed hydrogenation reactions; both were highly stereoselective, giving convenient access to pivotal intermediates. This synthesis was modified to g
- Zhu, Ye,Loudet, Aurore,Burgess, Kevin
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scheme or table
p. 4392 - 4395
(2010/12/18)
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- First asymmetric total synthesis of aspinolide A
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The first total synthesis of aspinolide A has been achieved using ring-closing metathesis as a key step. The stereogenic centers were generated by means of hydrolytic kinetic resolution (HKR) of racemic epoxides.
- Chowdhury, Partha Sarathi,Gupta, Priti,Kumar, Pradeep
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scheme or table
p. 7018 - 7020
(2010/02/28)
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- Synthesis of the tricyclic core of vinigrol via an intramolecular diels-alder reaction
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Equation presented Herein, we present a successful synthesis of the tricyclic core of vinigrol (1). Our approach takes advantage of a highly regioselective intramolecular Diels-Alder reaction of the diene 11 to construct two rings of the tricyclic vinigro
- Grise, Christiane M.,Tessier, Guillaume,Barriault, Louis
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p. 1545 - 1548
(2008/02/02)
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- Synthetic studies on mycolactones: Synthesis of the mycolactone core structure through ring-closing olefin metathesis
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The mycolactone core structure 2a has been prepared through ring-closing olefin metathesis from diene 3 with exquisite E selectivity. The preparation of diene 3 included a highly efficient stereoselective synthesis of carboxylic acid 5. The mycolactone co
- Feyen, Fabian,Jantsch, Andrea,Altmann, Karl-Heinz
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p. 415 - 418
(2008/01/06)
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- A synthetic approach toward nitiol: Construction of two 1,22-dihydroxynitianes
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Synthetic work toward the total synthesis of nitiol has culminated in the construction of two epimeric hydroxylated derivatives, the 1,22- dihydroxynitianes. Key stereodefining steps in the construction of the A-ring fragment (13) were the use of a siloxy-epoxide rearrangement reaction, a Pauson-Khand reaction, a Norrish 1 photochemical cleavage reaction, and a highly regio- and stereoselective hydrostannylation reaction of an ynoate. The stereochemistry of the synthetically challenging C-ring fragment (20) was established using an Ireland-Claisen reaction and a Grubbs ring-closing metathesis process as key steps. The 12-membered B-ring of the nitiane skeleton was constructed using a copper-promoted Stille cross-coupling and a Kishi-Hiyama-Nozaki carbonyl addition reaction. Unfortunately, the carbonyl addition reaction produced hydroxyl functionality that could not be selectively removed. Consequently, a synthesis of epimeric 1,22-dihydroxynitianes, which are compounds that are structural hybrids of two natural products, nitiol and variculanol, was completed.
- Wilson, Michael S.,Woo, Jacqueline C. S.,Dake, Gregory R.
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p. 4237 - 4245
(2007/10/03)
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- (+)-Sorangicin A synthetic studies. Construction of the C(1-15) and C(16-29) subtargets
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(Chemical Equation Presented) Effective stereocontrolled syntheses of subtargets (-)-2 and (-)-4, comprising respectively the C(16-29) and C(1-15) tetrahydropyran and dihydropyran moieties of the potent antibiotic (+)-sorangicin A (1), have been achieved. The cornerstone for the synthesis of (-)-2 involved an aldol tactic exploiting 1,4-induction, followed in turn by an acid-mediated cyclization/ketalization and hydrosilane reduction promoted by TMSOTf, while construction of (-)-4 entailed a stereoselective conjugate addition/α-oxygenation sequence.
- Smith III, Amos B.,Fox, Richard J.,Vanecko, John A.
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p. 3099 - 3102
(2007/10/03)
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- Access to isocarbacyclin derivatives via substrate-controlled enolate formation: Total synthesis of 15-deoxy-16-(m-tolyl)-17,18,19,20- tetranorisocarbacyclin
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(Chemical Equation Presented) We describe a convergent and flexible synthesis of 15-deoxy-16-(m-tolyl)-17,18,19,20-tetranorisocarbacyclin (15-deoxy-TIC), a simple isocarbacyclin derivative. The synthesis takes advantage of two key step reactions: a regioselective deprotonation of the described ketone under substrate control which is then trapped, as the enol triflate, to generate the C6-C9α endocyclic double bond, followed by an sp2-sp3 Pd-catalyzed cross-coupling reaction (C5-C6) with a suitable primary alkyl Grignard reagent. Introduction of the C13-C14 (E)-double bond in the ω-side chain is performed by the Julia-Kocienski olefination.
- Sheddan, Neil A.,Mulzer, Johann
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p. 5115 - 5118
(2007/10/03)
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- One-pot regio- and stereoselective cyclization of 1,2,n-triols
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A simple and efficient process to cyclize triols containing a 1,2-diol functionality with a pendant hydroxyl group is presented. The one-pot procedure converts the 1,2-diol into an ortho ester in situ, which upon treatment with a Lewis acid generates a cyclic acetoxonium intermediate. This intermediate is subsequently trapped by the pendant hydroxyl group to generate a cyclic ether. The stereochemistry of the 1,2-diol is transferred to the product with complete fidelity (inversion at the site of cyclization), and the reaction proceeds with high regioselectivity. The process is akin to the Lewis acid-catalyzed intramolecular ring-opening of epoxides with hydroxyl groups yielding cyclic ethers of various sizes with regio- and stereochemical control. Copyright
- Zheng, Tao,Narayan, Radha S.,Schomaker, Jennifer M.,Borhan, Babak
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p. 6946 - 6947
(2007/10/03)
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- Total synthesis of the epoxy isoprostane phospholipids PEIPC and PECPC
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(Chemical Equation Presented) A total synthesis of the naturally occurring hydroxy ketone PEIPC 1, a compound that plays a role in endothelial activation in atherosclerosis, has been completed via a triply convergent preparation of a protected EI derivative 13 from 3,5-diacetoxycyclopentene 7, pentane-1,5-diol, and vinyllithium, using Sharpless epoxidation and enzymatic resolution as key steps. Final coupling with lyso-PC 16 and silyl group deprotection gave PECPC 2 and PEIPC 1, which showed the same activity as natural PECPC and PEIPC.
- Jung, Michael E.,Berliner, Judith A.,Angst, Daniela,Yue, Dawei,Koroniak, Lukasz,Watson, Andrew D.,Li, Rongsong
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p. 3933 - 3935
(2007/10/03)
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- Synthetic studies on macrolactin A by using a (diene)Fe(CO)3 complex
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The stereoselective synthesis of the two segments 3 and 4 of macrolactin A 1 is described. Macrolactin A is a 24-membered polyene macrolide antibiotic, which is of interest due to a strong activity against B16-F10 murine tumor cell and HIV-1 virus. The ke
- Fukuda, Akihiro,Kobayashi, Yusuke,Kimachi, Tetsutaro,Takemoto, Yoshiji
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p. 9305 - 9313
(2007/10/03)
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- Stereocontrolled total synthesis of the Stemona alkaloid (-)-stenine
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The Stemona alkaloid stenine (1), isolated from Stemona tuberosa of physiologically active stemonaceous plants, possesses the structurally novel and unique azepinoindole skeleton (B,C,D-ring system). We have achieved the asymmetric total synthesis of (-)-
- Morimoto, Yoshiki,Iwahashi, Maki,Kinoshita, Takamasa,Nishida, Koji
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p. 4107 - 4116
(2007/10/03)
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- Facile and selective cleavage of allyl ethers, amines and esters using polymethylhydrosiloxane-ZnCl2/Pd(PPh3)4
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Allyl deprotection to liberate free hydroxy, amino and acid groups from the corresponding allyl ethers, amines and esters is achieved under mild conditions. The reagent combination employed for this transformation is polymethylhydrosiloxane (PMHS), ZnCl2 and Pd(PPh3)4.
- Chandrasekhar,Raji Reddy,Jagadeeshwar Rao
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p. 3435 - 3438
(2007/10/03)
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- Soybean lipoxygenase and horseradish peroxidase catalysed asymmetric oxidation-reduction sequence for the synthesis of chiral (Z,E) diene-diols
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Unnatural synthetic substrates with a properly spaced prosthetic modifier having non-ionic hydroxy terminus undergoes soybean lipoxygenase catalysed asymmetric peroxidation followed by horseradish peroxidase induced reduction affords (Z, E)-dienediol in high enantiomeric excess.
- Yadav,Nanda,Bhaskar Rao
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p. 787 - 788
(2007/10/03)
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- Enzymatic asymmetric hydroxylation of unnatural substrates with soybean lipoxygenase
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Surrogate substrates mimicking the natural substrate (linoleic acid) bearing a spacing prosthetic group with a non-ionic hydroxyl terminus undergo asymmetric hydroxylation with soybean lipoxygenase. The prosthetic modifier supplies the missing structural features needed for enzymatic recognition and controls the regiochemical outcome of the reaction by its high hydrophobic content. The effect of pH on the regiochemistry clearly shows that all the substrates can arrange themselves at the active site of soybean lipoxygenase in only one orientation leading to formation of hydroperoxides by oxygenation at the ω-6 carbon.
- Yadav,Nanda,Rao
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p. 2129 - 2135
(2007/10/03)
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- Asymmetric epoxide cyclisation route to the F-pyran fragment of the altohyrtins and key aldol studies
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The evolution of an asymmetric synthesis of a differentially protected F-pyran ring of the altohyrtins is described, which relies on a key intramolecular cyclisation of a C43 hydroxyl group onto a C38-C39 epoxide. The C38-C39 epoxide stereochemistry was achieved through optimisation of substrate control. Key aldol studies towards coupling the F-pyran ring with an E-pyran ring precursor was investigated, but unsuccessful. (C) 2000 Elsevier Science Ltd.
- Anderson, James C.,McDermott, Benjamin P.,Griffin, Edward J.
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p. 8747 - 8767
(2007/10/03)
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- Synthesis of a C29-C51 subunit of spongistatin 1 (altohyrtin A) starting from (R)-3-benzyloxy-2-methylpropan-1-ol
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A protected C29-C51 subunit ((+)-38) of spongistatin 1 has been obtained. Key steps involve the aldol condensation of (3S,4R)-3-methyl-7-[(p- methoxybenzyl)oxy]-4-[(triethylsilyl)oxy]octan-2-one ((-)-6) with (tert- butyl)dimethylsilyl 4-deoxy-2,3-di-O-(methoxymethyl)-4-methyl-6-O-(tert- butyl)dimethylsilyl)-β-D-glycero-L-gluco-heptodialdo-1,5-pyranoside ((+)-7) and a C-glycosidation of (4R,7RandS,E)-7,8-dichloro-2-methylidene-1- (trimethylsilyl)oct-5-en-4-yl p-methoxybenzoate (16). Aldehyde (+)-7 was derived from (R)-3-benzyloxy-2-methylpropan-1-ol ((+)-10) in 13 formal steps but requiring the isolation of five intermediate products only. The longest linear synthetic scheme converts (+)-10 into (+)-38 in 2% overall yield (isolation of 11 intermediate products).
- Lemaire-Audoire, Sandrine,Vogel, Pierre
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p. 3346 - 3356
(2007/10/03)
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- A mild and selective cleavage of tritylethers by cerium(III) chloride
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Trityl ethers are selectively cleaved by cerium(III) chloride in high yields in refluxing acetonitrile under neutral reaction conditions. The method is compatible with other acid sensitive functional groups like acetonide, acetate, benzoate, BOC, Cbz, benzyl, TBDPS, PMB, allyl, methyl and tetrahydropyranyl ethers present in the molecule.
- Yadav,Subba Reddy
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p. 1275 - 1276
(2007/10/03)
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- Untersuchungen zur asymmetrischen Synthese von Stemona-Alkaloiden: Totalsynthese von (-)-Stenin
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Keywords: Alkaloide; Asymmetrische Synthesen; (-)-Stenin; Totalsynthesen
- Morimoto, Yoshiki,Iwahashi, Maki,Nishida, Koji,Hayashi, Yuji,Shirahama, Haruhisa
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p. 968 - 970
(2007/10/03)
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- Cascade radical mediated macrocyclisation-transannulation reactions leading to ring-fused bicycles
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The scope for tandem radical mediated macrocyclisation-transannulation processes in the elaboration of ring-fused carbocycles has been examined.Thus, a range of E-iodo dienones viz. 21, 30b, 40, 42 and 44 were first prepared using synthetic sequences based on sound literature precedent.Treatment of the iodo dienone 21 with Bu3SnH-AIBN led to a 3:2 mixture of trans- and cis-isomers of 1-decalone, 35 and 36, respectively, in a combined yield of 72percent, whereas the positional isomer 30b of 21 underwent 10-endo macrocyclisation and transannulation to a 1:1 mixture of trans-1-decalone 35 and cis-octahydroazulen-1-one 39 (combined yield 68percent), resulting from competitive 6-exo/5-exo transannular cyclisation from the intermediate cyclodecenone radical 38.In further investigations of the scope for sequential radical macrocyclisation-transannulations in the synthesis of bicyclic systems, the iodo dienone 40 was found to undergo regioselective cyclisation to the cis-tetralone 41 (50percent), whereas the iodo dienone 42 produced only (Z)-cyclooct-3-enone 54 and none of the expected bicyclooctanone 43 on treatment with Bu3SnH-AIBN.Only the 4-cyclopentylcyclohexanone 61, and none of the hoped for 7,6-bicyclic ketone 45, was produced from radical cyclisation of the iodo dienone 44.The differing reaction pathways followed by the iodo dienones 21, 30b, 40 and 42 have been rationalised in terms of the conformational preferences of the macrocyclic α-keto radical intermediates, e.g. 32, 38 and 52 involved in the various cyclisations supported by some preliminary MM2 studies and calculations.
- Pattenden, Gerald,Smithies, Allison J.,Tapolczay, David,Walter, Daryl S.
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- Synthesis of a Novel Acetylenic Ester, Methyl (E)-5-Octadecen-7,9-diynoate
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We, herein, report synthesis of methyl ester of (E)-5-octadecen-7,9-diynoic acid, one of the novel acetylenic fatty acids of Paramacrolobium caeruleum root bark with unique biological activity, by coupling synthesized C1 to C8 fragment with 1-decyne.
- Mhaskar, S.Y.,Lakshminarayana, G.
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p. 2001 - 2009
(2007/10/02)
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