17123-60-3Relevant academic research and scientific papers
Synthesis of a Tiacumicin B Protected Aglycone
Jeanne-Julien, Louis,Masson, Guillaume,Astier, Eloi,Genta-Jouve, Grégory,Servajean, Vincent,Beau, Jean-Marie,Norsikian, Stéphanie,Roulland, Emmanuel
, p. 4006 - 4009 (2017)
Tiacumicin B is an antibiotic endowed with the remarkable ability to interact with a new biological target, giving it an inestimable potential in the context of the ever-growing and worrisome appearance of resistances of bacteria and mycobacteria to antibiotics. The synthesis of an aglycone of tiacumicin B ready for glycosylation is reported. The key steps of this approach are a [2,3]-Wittig rearrangement, a Pd/Cu-catalyzed allene-alkyne cross-coupling, a E-selective cross-metathesis, and a final ring-size selective macrolactonization.
Cobalt-Catalyzed Allylic C(sp3)-H Carboxylation with CO2
Michigami, Kenichi,Mita, Tsuyoshi,Sato, Yoshihiro
supporting information, p. 6094 - 6097 (2017/05/08)
Catalytic carboxylation of the allylic C(sp3)-H bond of terminal alkenes with CO2 was developed with the aid of a Co/Xantphos complex. A wide range of allylarenes and 1,4-dienes were successfully transformed into the linear styrylacetic acid and hexa-3,5-dienoic acid derivatives in moderate to high yields, with excellent regioselectivity. The carboxylation showed remarkable functional group tolerability, so that selective addition to CO2 occurred in the presence of other carbonyl groups such as amide, ester, and ketone. Since styrylacetic acid derivatives can be readily converted into optically active γ-butyrolactones through Sharpless asymmetric dihydroxylation, this allylic C(sp3)-H carboxylation showcases a facile synthesis of γ-butyrolactones from simple allylarenes via short steps.
Enantioselective total synthesis of brevetoxin A: Unified strategy for the B, E, G, and J subunits
Crimmins, Michael T.,Ellis, J. Michael,Emmitte, Kyle A.,Haile, Pamela A.,McDougall, Patrick J.,Parrish, Jonathan D.,Zuccarello, J. Lucas
scheme or table, p. 9223 - 9234 (2010/04/25)
Brevetoxin A is a decacyclic ladder toxin that possesses 5-, 6-, 7-, 8-, and 9-membered oxacycles, as well as 22 tetrahedral stereocenters. Herein, we describe a unified approach to the B, E, G, and J rings based upon a ring-closing metathesis strategy from the corresponding dienes. The enolate technologies developed in our laboratory allowed access to the precursor acyclic dienes for the B, E, and G medium-ring ethers. The strategies developed for the syntheses of these four monocycles ultimately provided multigram quantities of each of the rings, supporting our efforts toward the completion of a convergent synthesis of brevetoxin A.
Diastereoselective, three-component cascade synthesis of tetrahydrofurans and tetrahydropyrans employing the tandem Mukaiyama aldol-lactonization process
Mitchell, T. Andrew,Zhao, Cunxiang,Romo, Daniel
supporting information; experimental part, p. 9544 - 9551 (2009/04/07)
(Chemical Equation Presented) A full account of studies leading to the development of a cascade sequence that generates as many as two C-C bonds, one C-O bond, and three new stereocenters providing substituted tetrahydrofurans (THFs) from simple γ-ketoaldehydes and thiopyridyl ketene acetals is described. The process involves a tandem Mukaiyama aldol-lactonization (TMAL) and accumulated evidence suggests the intermediacy of a silylated β-lactone that is intercepted by the pendant ketone. Formation of a cyclic oxocarbenium is followed by reduction with silicon-based nucleophiles leading to a highly diastereoselective synthesis of tetrahydrofurans. This cascade process has now been extended to the synthesis of tetrahydropyrans from simple δ-ketoaldehydes. The stereochemical outcome of the cascade processes described was determined by NOE correlations, coupling constant analysis, and X-ray crystallography of the derived oxygen heterocycles and is in accord with established and recently proposed models for nucleophilic additions to cyclic 5- and 6-membered oxocarbenium ions. The utility of this process was demonstrated by the synthesis of the tetrahydrofuran fragment of colopsinol B.
Additive effects of ligand activated allylation of aldehydes by allyltrichlorosilane
Short, Joanne D.,Attenoux, Sandrine,Berrisford, David J.
, p. 2351 - 2354 (2007/10/03)
The rate of allylation of aldehydes using a combination of allyltrichlorosilane and O-donor ligands can he profoundly accelerated by the addition of a range of simple tetra-n-butylammonium salts. Measured tin values decrease from over 6 hours under define
REACTION OF UNSATURATED DERIVATIVES OF EPICHLOROHYDRIN WIHT MAGNESIUM
Akhmedov, M. A.,Akhmedov, I. M.,Mustafaeva, Z. G.,Sardarov, I. K.,Kostikov, R. R.,Musaeva, Kh. E.
, p. 1087 - 1088 (2007/10/02)
The reaction of alkenyl-substituted epichlorohydrins with magnesium in THf gave alkenyl-substituted cyclopropanols and allyl alcohols.
ALLYLSTANNATION. VII. A FACILE METHOD FOR THE SYNTHESYS OF 1,5-DIEN-4-OLS BY REACTION OF Bu2ClSnCH2CH=CH2 WITH α,β-UNSATURATED CARBONYL COMPOUNDS
Boaretto, Andrea,Marton, Daniele,Silvestri, Rosanna,Tagliavini, Giuseppe
, p. 391 - 392 (2007/10/02)
1,5-Dien-4-ols are easily prepared in high yield via allylstannation by reacting dibutylallyltin chloride with α,β-unsaturated carbonyl compounds.A comparison with the previous synthetic procedures, mainly performed via Grignard reagents, is made.
