32833-70-8Relevant academic research and scientific papers
Influence of the acetylenic substituent on the intramolecular carbolithiation of alkynes
Girard, Anne-Lise,Lhermet, Rudy,Fressigne, Catherine,Durandetti, Muriel,Maddaluno, Jacques
scheme or table, p. 2895 - 2905 (2012/06/29)
The intramolecular carbolithiation of a series of propargylic ethers has been performed to evaluate the influence of the terminal substituent on the efficiency and the stereochemical outcome of the cyclization. Our results show that only 5-exo-dig cyclizations are observed, and dihydrobenzofurans are obtained exclusively. Depending on the nature of the terminal substituent, two cases can be considered. If the terminal substituent carried by the acetylenic carbon atom is itself a carbon atom, the cyclization can occur provided the terminal propargylic position bears a coordinating element and is at least disubstituted. When the cyclization occurs, it follows an anti-carbolithiation pathway and thus leads to the E isomer of the exocyclic double bond. Only in one case (Ph) was a mixture of the E and Z isomers of the resulting olefin recovered. The cyclization can also take place if the alkyne is directly substituted by S or Si, provided the cyclization conditions are tuned. In the case of the trimethylsilyl substituent, a syn-carbolithiation was observed. If the double bond is recovered, in most cases, in the exocyclic position, the products can aromatize directly for SPh-substituted substrate 24. Furthermore, in the two latter cases, when alkylation of the vinyllithium intermediate is performed, isomerization of the double bond seems instantaneous. Copyright
Selective formation of six-membered oxa- and carbocycles by the In(III)-activated ring closure of acetylenic substrates
Qiu, Wen-Wei,Surendra, Karavadhi,Yin, Liang,Corey
supporting information; experimental part, p. 5893 - 5895 (2011/12/16)
Fifteen examples are disclosed of efficient In(III)-catalyzed six-membered ring closure leading to bi-, tri-, and tetracyclic products.
Method for preparing hydroxamic acids
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Page/Page column 5, (2010/02/14)
Processes for using a compound of formula III: to make compounds of formulae I and II: and processes for making the compound of formula III, where R1-5 and J are as defined herein.
16-Substituted polyunsaturated hexadecanoic fatty acids
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, (2008/06/13)
Sixteen carbon atom carboxylic acids having 16-phenoxy or 16-phenylthio substituents, and 0, 1, or 4 triple bonds, methods of preparing them, and pharmaceutical preparations containing them. These compounds are useful as lipoxygenase inhibitors.
Arachidonic acid analogs
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, (2008/06/13)
Long chain unsaturated hydrocarbon derivatives, having from 13 to 21 carbon atoms, which are substituted at the 1-position by a phenoxy, phenylthio or a phenyl that bear a carboxylic acid group at the ortho, meta or para positions, and up to 4 carbon-carbon triple bonds, methods of preparing them, and pharmaceutical preparations containing them. These compounds are useful as lipoxygenase inhibitors, and therefore as antiinflammatory agents.
PROSTANOIDS. XV. SYNTHESIS OF THE ARYL-SUBSTITUTED ANALOGS OF LEUCOTRIENES A4 AND E4
Tolstikov, G. A.,Tolstikov, A. G.,Miftakhov, M. S.,Spirikhin, L. V.
, p. 1457 - 1463 (2007/10/02)
(+/-)-16-Phenoxy-17,18,19,20-tetranorleucotriene-A4 methyl ester, (+/-)-16-phenoxy-17,18,19,20-tetranorleucotriene-E4 dimethyl ester, (+/-)-16-oxa-14,15-dinor-13,16-inter-o-phenyleneleucotriene-A4 methyl ester,and (+/-)-16
