137496-68-5Relevant academic research and scientific papers
Novel chiral amine oxide ligand and preparation method thereof
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Paragraph 0086; 0090; 0099; 0100; 0101; 0102; 0129-0132, (2019/05/15)
The invention provides a novel chiral amine oxide ligand and a preparation method thereof. The method uses a simple amino acid or an amino acid derivative as a raw material, the raw material is modified, the modified material reacts with substances such as a coupling agent and an alkali, and therefore the pincher configuration chiral ligand compound is obtained, that is, the chiral amine oxide ligand. The chiral amine oxide ligand provided by the invention has a structure of a non-simple linear chain, has a soft skeleton in the molecular structure, contains a recognition gene containing heteroatoms such as oxygen or nitrogen, and can well coordinate with a series of metals and realize high enantioselectivity and high reactivity in a non-symmetric reaction; and the preparation method is simple, the steps are few, and the raw materials are cheap and easy to obtain.
Organocatalytic Nitroaldol Reaction Associated with Deuterium-Labeling
Yamada, Tsuyoshi,Kuwata, Marina,Takakura, Ryoya,Monguchi, Yasunari,Sajiki, Hironao,Sawama, Yoshinari
, p. 637 - 641 (2017/12/13)
A deuterium-labeling reaction of nitroalkanes in deuterium oxide and the subsequent nitroaldol reaction have been accomplished under basic and organocatalytic conditions to provide the deuterium-labeled β-nitroalcohols in high yields and high deuterium contents. β-Deuterated β-nitroalcohols could be smoothly obtained from the reaction of nitroalkanes and various electrophiles using the easily-removal basic resin WA30. Furthermore, the asymmetric nitroaldol reaction using nitromethane and α-keto esters as electrophiles in the presence of a quinine-derived organocatalyst in deuterium oxide could provide the desired β-deuterated nitroalcohol derivatives with high enantioselectivities. (Figure presented.).
NITROGEN RING LINKED DEOXYURIDINE TRIPHOSPHATASE INHIBITORS
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, (2018/06/12)
Provided herein are dUTPase inhibitors, compositions comprising such compounds and methods of using such compounds and compositions.
Asymmetric Sulfinylations of N-Methylephedrine-Modified Tri- or Tetraalkyl Zincates by Symmetric Diaryl Sulfoxides
Ruppenthal, Simon,Brückner, Reinhard
supporting information, p. 2518 - 2530 (2018/06/11)
Diethylzinc was treated with 1 or 2 equiv. of AlkMgCl or PhMgBr (preferably) or with 1 equiv. of nBuLi (less efficiently) for forming species – plausibly zincates – which were sulfinylated by diaryl sulfoxides to give racemic alkyl aryl sulfoxides in yields reaching 100 %. Dialkylzinc reagents were also activated by treatments with 1 or 2 equiv. of an enantiomerically pure alkylmagnesium β-aminoalkoxide. This worked best when the alkoxide stemmed from a dialkylmagnesium reagent and an equimolar amount of N-methyl-(–)-ephedrine. This second activation mode allowed sulfinylations of what was originally the dialkylzinc reagent with diaryl sulfoxides. This generated alkyl aryl sulfoxides with enantiomeric ratios up to 93:7 in up to 100 % yield.
COMPOUNDS, COMPOSITIONS AND METHODS FOR SYNTHESIS
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Paragraph 001345; 001346; 001347; 001348, (2019/01/10)
The present disclosure, among other things, provides technologies for synthesis, including reagents and methods for stereoselective synthesis. In some embodiments, the present disclosure provides compounds useful as chiral auxiliaries. In some embodiments, the present disclosure provides reagents and methods for oligonucleotide synthesis. In some embodiments, the present disclosure provides reagents and methods for chirally controlled preparation of oligonucleotides. In some embodiments, technologies of the present disclosure are particularly useful for constructing challenging internucleotidic linkages, providing high yields and stereoselectivity.
Aluminium, gallium and indium complexes supported by a chiral phenolato-prolinolato dianionic ligand
Maudoux, Nicolas,Tan, Eric,Hu, Yuya,Roisnel, Thierry,Dorcet, Vincent,Carpentier, Jean-Fran?ois,Sarazin, Yann
, p. 131 - 143 (2016/12/14)
Congeneric complexes (S)-{?O}MCH2SiMe3 (M=Al, 3; Ga, 5; In, 6) of the triel metals supported by an enantiomerically pure phenolato-alkoxo {?O}2- dianionic tridentate ligand derived from prolinol, along with their chloro derivatives, have been prepared and characterised. The aluminium-alkyl species (S)-{?O}AlMe and 3 form four-coordinate complexes with slightly distorted tetrahedral geometries, whereas the geometry in the Lewis acidic five-coordinate (S)-{?O}GaCl·THF is a distorted trigonal bipyramid. These alkyl complexes do not react cleanly, if at all, with protic sources. The indium(III) compound 6, which is for instance inert towards iPrOH or BnOH even after hours at 70°C, catalyses at 95°C the controlled, immortal ring-opening polymerisation of racemic lactide (up to 1000 equivalents) in the presence of excess BnOH as a chain transfer agent. It affords atactic, monodisperse polylactides with predictable molecular weights.
Organocatalytic enantioselective α-hydroxymethylation of aldehydes: Mechanistic aspects and optimization
Boeckman, Robert K.,Biegasiewicz, Kyle F.,Tusch, Douglas J.,Miller, John R.
, p. 4030 - 4045 (2015/05/05)
Further studies of the direct enantioselective α-hydroxymethylation of aldehydes employing the α,α-diarylprolinol trimethylsilyl ether class of organocatalysts are described. This process has proven efficient for access to β-hydroxycarboxylic acids and δ-hydroxy-α,β-unsaturated esters from aldehydes in generally good yields, excellent enantioselectivity, and compatibility with a broad range of functional groups in the aldehyde. The goal of these studies was to identify the critical reaction variables that influence the yield and enantioselectivity of the α-hydroxymethylation process such as catalyst structure, pH of the medium, purity of the reactants and reagents particularly with respect to the presence of acidic impurities, and the nature of the buffer, along with the standard variables including solvent, time, temperature and mixing efficiency. The previously identified intermediate lactol has been further characterized and its reactivity examined. These studies have led to identification of the most critical variables translating directly into improved substrate scope, reproducibility, enantioselectivity, and yields.
Asymmetric lithiation trapping of N -boc heterocycles at temperatures above -78°C
Gelardi, Giacomo,Barker, Graeme,O'Brien, Peter,Blakemore, David C.
supporting information, p. 5424 - 5427 (2013/11/19)
The asymmetric lithiation trapping of N-Boc heterocycles using s-BuLi/chiral diamines at temperatures up to -20°C is reported. Depending on the N-Boc heterocycle, lithiation is accomplished using s-BuLi and (-)-sparteine or the (+)-sparteine surrogate in the temperature range -50 to -20°C for short reaction times (2-20 min). Subsequent electrophilic trapping or transmetalation-Negishi coupling delivered functionalized N-Boc heterocycles in 47-95% yield and 77:23-93:7 er. With N-Boc pyrrolidine, trapped products can be generated in ～90:10 er even at -20°C.
Highly enantioselective henry reactions in water catalyzed by a copper tertiary amine complex and applied in the synthesis of (S)-N-trans-feruloyl octopamine
Lai, Guoyin,Guo, Fengfeng,Zheng, Yueqin,Fang, Yang,Song, Haigang,Xu, Kun,Wang, Sujing,Zha, Zhenggen,Wang, Zhiyong
, p. 1114 - 1117 (2011/03/21)
It's in the water! A new copper tertiary amine complex was prepared and applied in asymmetric Henry reactions in water and in the short synthesis of (S)-N-trans-feruloyl octopamine. This catalytic system provided an approach to the enantioselective Henry reaction of aldehydes with hydroxyl substituents (see graphic).
