85116-38-7Relevant academic research and scientific papers
Double diastereoselection in asymmetric [2+3] cycloaddition of chiral oxazoline N-oxides: Application to the kinetic resolution of a racemic α,β-unsaturated δ-lactone
Dirat, Olivier,Kouklovsky, Cyrille,Langlois, Yves,Lesot, Philippe,Courtieu, Jacques
, p. 3197 - 3207 (1999)
The asymmetric [2+3] cycloaddition reaction between chiral oxazoline N-oxide 1 and α,β-unsaturated lactone 2 was studied. A double diastereoselection was observed, (1R)-1 and (R)-2 gave a mismatched pair with almost no cycloadduct obtained. A transition state model is proposed, accounting for the destabilization of transition state in the cycloaddition reaction. This result has led to kinetic resolution studies, in which both enantiomers of 1 were reacted with racemic lactone 2. The enantiomeric excess of the recovered lactone 2 was determined to be up to 70% ee, by 13C-{1H} NMR analysis in a chiral liquid crystalline solvent. The experimental results are in agreement with predicted enantiomeric excesses and consistent with the transition state models.
Synthesis of (+)-spirolaxine methyl ether
Nannei, Raffaella,Dallavalle, Sabrina,Merlini, Lucio,Bava, Adriana,Nasini, Gianluca
, p. 6277 - 6280 (2006)
A short and efficient synthesis of (+)-spirolaxine methyl ether, a metabolite of the fungus Sporotrichum laxum with inhibitory activity against Helicobacter pylori, is described. The synthesis has been carried out by a Prins cyclization, to obtain the [6,
Approach to the Core Structure of 15- epi -Exiguolide
Riefert, Alexander,Maier, Martin E.
, p. 3131 - 3145 (2018/08/17)
The synthesis of seco acid 41 of the macrolactone part of 15- epi -exiguolide, containing a bis-pyran subunit and a trans double bond, is described. Key features of the synthetic strategy include a Feringa-Minnaard asymmetric organocuprate addition to uns
Convergent total synthesis of (±) myricanol, a cyclic natural diarylheptanoid
Bochicchio,Schiavo,Chiummiento,Lupattelli,Funicello,Hanquet,Choppin,Colobert
, p. 8859 - 8869 (2018/11/30)
Myricanol 1, a constituent of Myrica species, has been reported to lower the levels of the microtubule-associated protein tau (MAPT), whose accumulation plays an important role in some neurodegenerative diseases, such as Alzheimer's disease (AD). Herein w
Studies on C18-C20 aldol couplings of rhizopodin
Dieckmann, Michael,Rudolph, Sven,Lang, Carolin,Ahlbrecht, Wiebke,Menche, Dirk
, p. 2305 - 2315 (2013/09/02)
The aldol addition of an enol(ate) to a carbonyl compound is one of the most powerful and versatile C-C bond forming reactions. In complex target synthesis the coupling of two chiral partners may complicate the stereochemical outcome by multiple stereoinductions. Here, we report studies on pivotal aldol couplings employed in the rhizopodin synthesis, detailing the various directing effects exerted by the stereogenic centers present in this sterically hindered connection. Georg Thieme Verlag Stuttgart. New York.
Structural variants of mycolactones for use in modulating inflammation, immunity and pain
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Paragraph 0110-0113, (2013/06/05)
The present invention is related to variants of mycolactones of formula (I), processes for the preparation thereof, pharmaceutical compositions thereof and their use in modulating inflammation, immunity and pain. ???????? Y-O-W?????(I) wherein Y and W are as defined in claim 1.
Syntheses of (-)-cryptocaryolone and (-)-cryptocaryolone diacetate via a diastereoselective oxy-Michael addition and oxocarbenium allylation
Albury, Aymara M. M.,Jennings, Michael P.
experimental part, p. 6929 - 6936 (2012/10/08)
The total syntheses of both (-)-cryptocaryolone and (-)-cryptocaryolone diacetate is presented herein. The usage of a diastereoselective oxy-Michael addition/benzylidene acetal formation coupled with a selective axial oxocarbenium allylation allowed for the preparation of the α-C-glycoside moiety present in the bicyclic bridged structure. In addition, the syn-1,3-diol of the linear portion was installed via a Wacker oxidation followed by a subsequent directed reduction of the appropriate homoallylic alcohol precursor.
An efficient total synthesis of (-)-epothilone B
Wang, Jie,Sun, Bing-Feng,Cui, Kai,Lin, Guo-Qiang
supporting information, p. 6354 - 6357 (2013/02/23)
An efficient total synthesis of (-)-epothilone B has been achieved in ca. 8% yield over 11 steps from 9 (or 10 steps from 7/8), which features a bissiloxane-tethered ring closing metathesis reaction to approach the trisubstituted (Z) double bond and forms a new basis for further development of an industrial process for epothilone B and ixabepilone.
Direct synthesis of B-allyl and B-allenyldiisopinocampheylborane reagents using allyl or propargyl halides and indium metal under Barbier-type conditions
Hirayama, Lacie C.,Haddad, Terra D.,Oliver, Allen G.,Singaram, Bakthan
supporting information; experimental part, p. 4342 - 4353 (2012/06/30)
We report the first one-pot process for the asymmetric addition of allyl, methallyl, and propargyl groups to aldehydes and ketones using B-chlorodiisopinocampheylborane (dDIP-Cl) and indium metal. Under Barbier-type conditions, indium metal was
Enantio- and diastereoselective synthesis of (E)-1,5-syn-diols: Application to the synthesis of the C(23)-C(40) fragment of tetrafibricin
Kister, Jeremy,Nuhant, Philippe,Lira, Ricardo,Sorg, Achim,Roush, William R.
supporting information; experimental part, p. 1868 - 1871 (2011/06/22)
A highly stereoselective synthesis of (E)-1,5-syn-diols 6 is described. The kinetically controlled hydroboration of allenyltrifluoroborate 8 with Soderquist borane 2 provides the (Z)-allylic trifluoroborate 9, which undergoes sequential allylboration with two different aldehydes to provide (E)-1,5-syn-diols 6 in 72-98% yields with >95% ee and >20:1 dr. Application of this method to the synthesis of the tetrafibricin C(23)-C(40) fragment 19 is described.
