69125-55-9Relevant academic research and scientific papers
Total synthesis of aeruginosin 98B
Trost, Barry M.,Kaneko, Toshiyuki,Andersen, Neil G.,Tappertzhofen, Christoph,Fahr, Bruce
supporting information, p. 18944 - 18947 (2013/01/15)
The first total synthesis of aeruginosin 98B was accomplished. The key step is a highly diastereoselective Pd-catalyzed intramolecular asymmetric allylic alkylation reaction of a diastereomeric mixture of allylic carbonates that is enabled by the use of racemic phosphine ligand L1.
Stille-heck coupling sequences applied in a versatile new access to steroid skeletons
Suennemann, Hans Wolf,Hofmeister, Anja,Magull, Joerg,De Meijere, Armin
, p. 3739 - 3756 (2008/02/08)
A variety of enantiomerically pure steroidal compounds was synthesized utilizing a sequence of Stille and Heck cross-coupling reactions and subsequent thermal 6π-electrocyclizations. Highly chemoselective Stille couplings on the triflate moiety of several
Ionic-liquid-like copolymer stabilized nanocatalysts in ionic liquids: II. Rhodium-catalyzed hydrogenation of arenes
Zhao, Chen,Wang, Han-zhi,Yan, Ning,Xiao, Chao-xian,Mu, Xin-dong,Dyson, Paul J.,Kou, Yuan
, p. 33 - 40 (2008/09/18)
Rhodium nanoparticles stabilized by the ionic-liquid-like copolymer poly[(N-vinyl-2-pyrrolidone)-co-(1-vinyl-3-butylimidazolium chloride)] were used to catalyze the hydrogenation of benzene and other arenes in ILs. The nanoparticle catalysts can endure forcing conditions (75 °C, 40 bar H2), resulting in high reaction rates and high conversions compared with other nanoparticles that operate in ILs. The hydrogenation of benzene attained record total turnovers of 20,000, and the products were easily separated without being contaminated by the catalysts. Other substrates, including alkyl-substituted arenes, phenol, 4-n-propylphenol, 4-methoxylphenol, and phenyl-methanol, were studied and in most cases were found to afford partially hydrogenated products in addition to cyclohexanes. In-depth investigations on reaction optimization, including characterization of copolymers, transmission electron microscopy, and an infrared spectroscopic study of nanocatalysts, were also undertaken.
Imidazo heterocyclic compounds
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, (2011/07/06)
A novel class of imidazo heterocyclic compounds, pharmaceutical compositions comprising them and use thereof in the treatment and/or prevention of diseases and disorders related to the histamine H3 receptor. More particularly, the compounds are useful for the treatment and/or prevention of diseases and disorders in which an interaction with the histamine H3 receptor is beneficial.
Thermal -Sigmatropic Shift of Previtamin D3 to Vitamin D3: Synthesis and Study of Pentadeuterio Derivatives
Okamura, William H.,Elnager, Hassan Y.,Ruther, Michael,Dobreff, Susanne
, p. 600 - 610 (2007/10/02)
Specifically pentadeuteriated previtamin D3 11 has been synthesized to impart thermal stability to the otherwise labile material.A 12-step synthesis of the trideuteriated A-ring 14b from p-methoxyphenol was developed and employed the addition of (methyl-d3)magnesium iodide to either the keto thiomethylene intermediate 23 or the keto dioxane 27.The enantiomerically pure trideuterio A-ring (-)-14b was then coupled with the deuteriated CD fragment 13b followed by hydrogenation to afford pentadeuteriated previtamin D3 11.A primary deuterium kinetic isotope effect (KIE) study of the -sigmatropic hydrogen migration in the conversion of previtamin D3 to vitamin D3 indicated a more "normal" primary deuterium isotope effect (as compared to a previously reported literature value of ca. 45).At 80 deg C, a kH/kD for the previtamin D3 to vitamin D3 isomerization was determined to be ca. 6.2.At 25 deg C, this -sigmatropic hydrogen migration proceeds with a kH/kD of ca. 11.4.The revisible, first-order -sigmatropic hydrogen shift of previtamin D3 to D3, determined over the temperature range 60.1-85.5 deg C is characterized by the following activation parameters: log AH = 8.8 and EaH = 19.6 kcal/mol.Deuteriated pre-D3, which rearranges over this temperature range, is characterized by the activation parameters log AD = 9.5 and EaD = 21.9 kcal/mol.
SYNTHESIS OF 1-HYDROXY-7-AZATRICYCLO2.7>DODECAN-9-ONES: POTENTIAL INTERMEDIATES FOR THE TOTAL SYNTHESIS OF SECURININES
Cote, Roland,Bouchard, Pierre,Couture, Yvon,Furstoss, Roland,Waegell, Bernard,Lessard, Jean
, p. 987 - 998 (2007/10/02)
A synthesis of epimeric 1-hydroxy-7-azatricyclo2.7>dodecan-9-ones (3 and 4), in ten steps from p-methoxyphenol, is described.They have been converted to the corresponding 9(10)-olefinic derivatives 22 and 23.
The Synthesis of Tricyclic Naphtho Fused Frameworks via Isoquinolinium Salts
Franck, Richard W.,Gupta, Ram B.
, p. 293 - 296 (2007/10/02)
The cycloaddition of the enol ethers of cyclic ketones with isoquinolinium salts is the key step in a general preparation of interesting tricyclic naphthalene derivatives.
