- Efficient and Divergent Synthesis of α-Halogenated Amides and Esters by Double Electrophilic Activation of Ynamides
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An efficient and modular entry to α-halogenated amides and esters is reported. This reaction is based on an underestimated double electrophilic activation of ynamides sequentially involving highly reactive activated keteniminium and iminium ions. Upon simple reaction with HCl and an electrophilic halogenation reagent in the presence of water or an alcohol, a broad range of ynamides can be transformed, in a highly divergent manner, to α-halo amides and esters with high efficiency and under mild conditions.
- Thilmany, Pierre,Evano, Gwilherm
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- Ni-Catalyzed Regiodivergent and Stereoselective Hydroalkylation of Acyclic Branched Dienes with Unstabilized C(sp3) Nucleophiles
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Two complementary regiodivergent [(P,N)Ni]-catalyzed hydroalkylations of branched dienes are reported. When amides are employed as unstabilized C(sp3) nucleophiles, a highly regioselective 1,4-addition process is favored. The addition products are obtained in high yield and with excellent stereocontrol of the internal olefin. With use of a chiral ligand and imides as carbon nucleophiles, a 3,4-addition protocol was developed, enabling construction of two contiguous tertiary stereocenters in a single step with moderate to high levels of diastereocontrol and excellent enantiocontrol. Both methods operate under mild reaction conditions, display a broad scope, and show excellent functional group tolerance. The synthetic potential of the 3,4-hydroalkylation reaction was established via a series of postcatalytic modifications.
- Shao, Wen,Besnard, Céline,Guénée, Laure,Mazet, Clément
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p. 16486 - 16492
(2020/10/26)
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- Design, synthesis, and biological evaluation of oxazolidone derivatives as highly potent N-acylethanolamine acid amidase (NAAA) inhibitors
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N-Acylethanolamine-hydrolyzing acid amidase (NAAA) is a lysosomal enzyme that catalyzes the hydrolysis of endogenous fatty acid ethanolamides (FAEs), such as N-palmitoylethanolamide (PEA). PEA exhibits anti-inflammatory and analgesic activities by engaging peroxisome proliferator-activated receptor α (PPAR-α). Preventing PEA degradation by inhibition of NAAA has been proposed as a novel strategy for the treatment of inflammation and pain. In the present study, we reported the discovery of the oxazolidone derivative as a novel scaffold for NAAA inhibitors, and studied the structure-activity relationship (SAR) by modification of the side chain and terminal lipophilic substituents. The results showed that the link chain length of C5, straight and saturated linkages were the preferred shape patterns for NAAA inhibition. Several nanomolar NAAA inhibitors were described, including 2f, 3h, 3i and 3j with IC50 values of 270 nM, 150 nM, 100 nM and 190 nM, respectively. Enzymatic degradation studies suggested that 2f inhibited NAAA in a selective, noncompetitive and reversible pattern. Moreover, 2f showed high anti-inflammatory and analgesic activities after systemic and oral administration.
- Ren, Jie,Li, Yuhang,Ke, Hongwei,Li, Yanting,Yang, Longhe,Yu, Helin,Huang, Rui,Lu, Canzhong,Qiu, Yan
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p. 12455 - 12463
(2017/03/11)
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- REACTIVE OXYGEN SPECIES-BASED PRODRUGS
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Provided herein are ROS-sensitive prodrug compositions and methods of treating ROS-associated diseases by administering the ROS-sensitive prodrug compositions.
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Paragraph 0277; 0278; 0285
(2015/02/05)
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- Exploring hydrogen peroxide responsive thiazolidinone-based prodrugs
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A novel approach for developing prodrugs based on masked carboxylic acids is described. Rather than using conventional esterase-based activation, thiazolidinone protecting groups have been identified that can reveal carboxylic acid groups upon activation by hydrogen peroxide. This may prove valuable in the continuing development of prodrug strategies that rely on reactive oxygen species (ROS) as a trigger. This journal is
- Perez, Christian,Monserrat, Jean-Philippe,Chen, Yao,Cohen, Seth M.
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supporting information
p. 7116 - 7119
(2015/04/27)
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- A green synthetic route to imides from terminal alkynes and amides by simple solid catalysts
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An atom-efficient and green synthetic route to highly valuable imides (5492% yields) from terminal alkynes and amides has been developed. This new route is composed of two consecutive reactions, that is, (i) the reported Cu(OH)2-catalyzed cross-coupling o
- Jin, Xiongjie,Yamaguchi, Kazuya,Mizuno, Noritaka
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supporting information
p. 866 - 867
(2012/11/07)
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- Stereoselective synthesis of (E)-trisubstituted α,β-unsaturated amides and acids
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Potassium alkoxides of N-acyl-oxazolidin-2-one-syn-aldols undergo stereoselective elimination reactions to afford a range of trisubstituted (E)-αβ-unsaturated amides in >95% de, that may be subsequently converted into their corresponding (E)-αβ-unsaturated acids or (E)-αβ-unsaturated oxazolines in good yield. syn-Aldols derived from αβ-unsaturated aldehydes gave their corresponding trisubstituted (E)-αβ-unsaturated-amides with poorer levels of diastereocontrol, whilst there was a similar loss in (E)-selectivity during elimination of syn-aldols derived from chiral aldehydes. These elimination reactions proceed via rearrangement of the potassium alkoxide of the syn-aldol to a 1,3-oxazinane-2,4-dione enolate intermediate that subsequently eliminates carbon dioxide to afford a trisubstituted (E)-αβ-unsaturated amide. The (E)-selectivity observed during the ElcB-type elimination step has been rationalised using a simple conformational model that employs a chair-like transition state to explain the observed stereocontrol. The Royal Society of Chemistry 2005.
- Feuillet, Fred J. P.,Cheeseman, Matt,Mahon, Mary F.,Bull, Steven D.
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p. 2976 - 2989
(2007/10/03)
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- An (E)-selective synthesis of trisubstituted (E)-α, β-unsaturated acid derivatives
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Potassium alkoxides of N-acyloxazolidin-2-one derived synaldolates undergo a novel tandem intramolecular cyclisation elimination reaction to afford trisubstituted (E)-α,β-unsaturated amides in high d.e., which may be converted into their corresponding acids or oxazolines in good yield.
- Feuillet, Fred J. P.,Robinson, Diane E. J. E.,Bull, Steven D.
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p. 2184 - 2185
(2007/10/03)
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- A convenient method for synthesis of optically active methylphenidate from N-methoxycarbonylpiperidine by utilizing electrochemical oxidation and Evans aldol-type reaction
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A new method to prepare optically active methylphenidate starting from piperidine is described. The method consists of a transformation of N-methoxycarbonylated piperidine to the corresponding α-methoxylated carbamate utilizing electrochemical oxidation f
- Matsumura, Yoshihiro,Kanda, Yasuhisa,Shirai, Kimihiro,Onomura, Osamu,Maki, Toshihide
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p. 7411 - 7422
(2007/10/03)
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- Asymmetric synthesis of optically active 2,3-diarylsuccinic acids by oxidative homocoupling of chiral 3-(arylacetyl)-2-oxazolidones
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Oxidative homocoupling of chiral 3-(arylacetyl)-2-oxazolidones 1 was achieved by treatment with DABCO-TiCl4 or DMAP-TiCl4 and afforded the corresponding dimers stereospecifically. The reaction of (4S)- and (4R)-substituted 1 gave (S,S)- and (R,R)-dimers respectively. The obtained dimers were easily transformed to the corresponding 2,3-diaryl succinic acids. This reaction therefore provides a useful method For the synthesis of optically pure 2,3-diarylsuccinic acids. The oxidative coupling was not inhibited by para substitution of an electron donating group on the aryl group. A para-substituted electron withdrawing group and an ortho-substituent, however, hindered the coupling.
- Kise, Naoki,Kumada, Kimikage,Terao, Yuichi,Ueda, Nasuo
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p. 2697 - 2708
(2007/10/03)
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- Electrogenerated Superoxide-Activated Carbon Dioxide. A New Mild and Safe Approach to Organic Carbamates
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The electrochemical reduction of O2 (E = -1.0 V vs SCE) in dipolar aprotic solvents in the presence of CO2 gave a carboxylating reagent (O2·-/CO2) able to convert amines and different types of their derivatives into carbamates. Primary and secondary aliphatic and aromatic amines were converted into the corresponding ethyl carbamates by the addition of EtI to the carbamate anions generated in the first step of the reactions. The yields were dependent on the nucleophilicity of the nitrogen atom ω-Bromoethyl- and propylamine gave 2-oxazolidinone and tetrahydro-l,3-oxazm-2-one in moderate yields. N-Acyl or N-(alkoxycarbonyl)alkylamines bearing a leaving group at the β position of the alkyl substituent were converted into 3-substituted-2-oxazolidinones in high yields. By using chiral substrates, enantiopure 3-alkoxycarbonyl(or acyl)-4-substituted oxazolidin-2-ones (70-85% isolated yields) were obtained. This represents a new mild and safe route to these important auxiliaries for asymmetric synthesis. Some limitations of the process are also evidenced and accounted for.
- Casadei, Maria Antonietta,Moracci, Franco Micheletti,Zappia, Giovanni,Inesi, Achille,Rossi, Leucio
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p. 6754 - 6759
(2007/10/03)
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- Formation of N-Tributylstannyl Heterocycle from Bis(tributyltin) Oxide and ω-Haloalkyl Isocyanate. One-Pot Convenient Synthesis of 2-Oxazolidinones and Tetrahydro-2H-1,3-oxazin-2-one
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Novel types of compounds, N-tributylstannyl-2-oxazolidinone (4a) and tetrahydro-2H-1,3-oxazin-2-one (4b), are formed from the adduct of (n-Bu3Sn)2O (1) with ω-haloalkyl isocyanate (2), and the subsequent coupling reaction with alkyl halides gives a variety of N-substituted 2-oxazolidinones and tetrahydro-2-oxazinones in a one-pot procedure.Both the cyclization and the coupling reaction proceed quantitatively in the presence of HMPA which enhances the reactivity of the Sn-heteroatom bond by coordination.
- Shibata, Ikuya,Nakamura, Kenji,Baba, Akio,Matsuda, Haruo
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p. 853 - 859
(2007/10/02)
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