89358-30-5Relevant academic research and scientific papers
Gold-Catalyzed Asymmetric Thioallylation of Propiolates via Charge-Induced Thio-Claisen Rearrangement
Kim, Hanbyul,Jang, Jiwon,Shin, Seunghoon
supporting information, p. 20788 - 20795 (2020/11/27)
A gold(I)-catalyzed enantioselective thioallylation of propiolates with allyl sulfides is described. The key mechanistic element is a sulfonium-induced Claisen rearrangement which helps minimize the allyl dissociation and render higher enantioselectivity. This protocol features remarkable scope of the allyl moiety, allowing enantiocontrolled synthesis of all-carbon quaternary centers, and exhibits exceptional functional group compatibility with many Lewis bases and π-bonds. This intermolecular variant of Claisen rearrangement forges both C-S and C-C bonds concomitantly, providing efficient access to interesting optically active organosulfur compounds which can be transformed further through the vinyl sulfide as a functional handle. The rate of the reaction was zeroth order with respect to allyl sulfides, which suggested a reversible inhibition, providing a resting state for the catalyst. The Hammett plot displayed a correlation with σp values, suggesting a turnover-limiting sigmatropic rearrangement where decreased electron-density on sulfur accelerated the rearrangement.
Asymmetric synthesis of the fully elaborated pyrrolidinone core of oxazolomycin A
Donohoe, Timothy J.,O'Riordan, Timothy J. C.,Peifer, Manuel,Jones, Christopher R.,Miles, Timothy J.
supporting information, p. 5460 - 5463,4 (2012/12/12)
The asymmetric synthesis of the key pyrrolidinone core, including a highly elaborated exocyclic carbon chain, of the γ-lactam β-lactone antibiotic oxazolomycin A is described. Principal features include the Birch reduction of an aromatic pyrrole nucleus, a late stage RuO4 catalyzed pyrrolidine oxidation, and a highly diastereoselective organocerium addition to an aldehyde.
Asymmetric synthesis of the fully elaborated pyrrolidinone core of oxazolomycin A
Donohoe, Timothy J.,O'Riordan, Timothy J. C.,Peifer, Manuel,Jones, Christopher R.,Miles, Timothy J.
supporting information, p. 5460 - 5463 (2013/01/15)
The asymmetric synthesis of the key pyrrolidinone core, including a highly elaborated exocyclic carbon chain, of the γ-lactam β-lactone antibiotic oxazolomycin A is described. Principal features include the Birch reduction of an aromatic pyrrole nucleus, a late stage RuO4 catalyzed pyrrolidine oxidation, and a highly diastereoselective organocerium addition to an aldehyde.
Visible-light-mediated conversion of alcohols to halides
Dai, Chunhui,Narayanam, Jagan M.R.,Stephenson, Corey R.J.
experimental part, p. 140 - 145 (2012/02/06)
The development of new means of activating molecules and bonds for chemical reactions is a fundamental objective for chemists. In this regard, visible-light photoredox catalysis has emerged as a powerful technique for chemoselective activation of chemical bonds under mild reaction conditions. Here, we report a visible-light-mediated photocatalytic alcohol activation, which we use to convert alcohols to the corresponding bromides and iodides in good yields, with exceptional functional group tolerance. In this fundamentally useful reaction, the design and operation of the process is simple, the reaction is highly efficient, and the formation of stoichiometric waste products is minimized.
CYCLIC AMINE COMPOUND
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Page/Page column 149, (2009/04/23)
The present invention provides an excellent antihypertensive medicament. The medicament of the present invention comprises a compound having the general formula (I) and the like: [wherein R1: H, substitutable alkyl, substitutable alkenyl, substitutable cyclic hydrocarbon, substitutable heterocyclyl or the like; R2: H, substitutable alkyl, substitutable alkenyl, substitutable cycloalkyl or the like; R3, R4; H, substitutable alkyl, substitutable alkenyl, substitutable cycloalkyl or the like; R5, R6: H, substitutable alkyl, substitutable cycloalkyl, substitutable alkoxy or the like; R7, R8: H, substitutable alkyl, substitutable cycloalkyl or the like; X: the formula (II) or the like; A: substitutable cyclic hydrocarbon, substitutable heterocyclyl or the like; Y: a single bond, substitutable alkylene, substitutable alkenylene, -(CH2)a-X1-(CH2)b- (X1: the formula -NH-, -O- or the like; a, b: 0-5) or the like; B: substitutable cyclic hydrocarbon, substitutable heterocyclyl or the like].
NOVEL MACROCYCLIC PEPTIDES
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Page/Page column 26, (2009/12/27)
Disclosed are cyclosporine derivatives in which the 3-Sarcosine carbon and 5-Valine nitrogen are each substituted by a non-hydrogen substituent, and their use as pharmaceuticals, in particular for the treatment of hepatitis C virus.
The P1 N-isopropyl motif bearing hydroxyethylene dipeptide isostere analogues of aliskiren are in vitro potent inhibitors of the human aspartyl protease renin
Yamaguchi, Yasuchika,Menear, Keith,Cohen, Nissim-Claude,Mah, Robert,Cumin, Frédéric,Schnell, Christian,Wood, Jeanette M.,Maibaum, Jürgen
scheme or table, p. 4863 - 4867 (2010/05/18)
Novel nonpeptide small molecule renin inhibitors bearing an N-isopropyl P1 motif were designed based on initial lead structures 1 and aliskiren (2). (P3-P1)-Benzamide derivatives such as 9a and 34, as well as the corresponding P1 basic tertiary amine derivatives 10 and 35 were found to display low nanomolar inhibition against human renin in vitro.
N-heterocyclic carbene-catalyzed hydroacylation of unactivated double bonds
Hirano, Keiichi,Biju, Akkattu T.,Piel, Isabel,Glorius, Frank
supporting information; experimental part, p. 14190 - 14191 (2010/02/15)
(Chemical Equation Presented) An intramolecular N-heterocyclic carbene (NHC)-catalyzed hydroacylation of unactivated double bonds is reported. Systematic variation of the catalyst structure revealed an N- mesitylthiazolylidene annulated with a seven-membered ring to be especially reactive. This NHC enables a unique C-C bond-forming reaction to afford substituted chroman-4-ones in moderate to excellent yields, even ones containing all-carbon quaternary centers.
Furanose Synthesis via Regioselective Dihydroxylation of 1-Silyloxy-1,3-dienes: Application to the Furanose Unit of 4-epi-Hygromycin A
Armstrong, Alan,Gethin, David M.,Wheelhouse, Christopher J.
, p. 350 - 352 (2007/10/03)
Asymmetric dihydroxylation of a 1-silyloxy-1,3-diene is shown to occur regioselectively on the non-oxygenated alkene. Second dihydroxylation is complicated by over-oxidation to the dione and epimerisation of reaction products. However, subsequent manipula
A Cross Metathesis Based Protocol for the Effective Synthesis of Functionalised Allyl Bromides and Chlorides
Bandini, Marco,Cozzi, Pier Giorgio,Licciulli, Sebastiano,Umani-Ronchi, Achille
, p. 409 - 414 (2007/10/03)
Functionalised allyl halides, useful starting materials for the preparation of substituted organometallic reagents can be simply obtained by a straightforward approach. Hoveyda's ruthenium carbene catalyst 3, used in catalytic amount (2 mol%), is able to
