- Chemical switching in reaction behavior of azine: Synthesis of a novel thienodiazepine derivative
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We previously have reported that an acid-promoted condensation of a hydrazonoester derived from phenylalanine afforded an azine which was converted to a pyrrole through 3 steps: isomerization to dienamine, [3,3]-sigmatropic rearrangement, and cyclization.
- Ohtake, Kaoru,Tsuda, Jyunpei,Takatori, Kazuhiko,Nagumo, Shinji,Yasui, Eiko
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supporting information
(2021/04/15)
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- Wittig reactions in water media employing stabilized ylides with aldehydes. Synthesis of α,β-unsaturated esters from mixing aldehydes, α-bromoesters, and Ph3P in aqueous NaHCO3
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(Chemical Equation Presented) Water is demonstrated to be an effective medium for the Wittig reaction over a wide range of stabilized ylides and aldehydes. Despite sometimes poor solubility of the reactants, good chemical yields normally ranging from 80 to 98% and high E-selectivities (up to 99%) are achieved, and the rate of the reactions in water is unexpectedly accelerated. The efficiency of water as a medium in the Wittig reaction is compared to conventional organic solvents ranging from carbon tetrachloride to methanol. The aqueous Wittig reaction works best when large hydrophobic entities are present, such as aromatic, heterocyclic aromatic carboxaldehydes, and long-chain aliphatic aldehydes with triphenylphosphoranes. The E/Z-isomeric ratio of the Wittig products appears dependent on the electron-accepting/donating capacity and the location of the substituents present in the aromatic ring. The effect of additives, such as benzoic acid, LiCl, and sodium dodecyl sulfate (SDS), on the Wittig reaction has been explored. The Wittig reaction can also be conducted in the presence of acidic entities, such as phenols and carboxylic acids. In addition, large α-substituents in the aliphatic aldehydes do not jeopardize the reaction. It is also demonstrated that hydrates of aldehydes can be used directly in the aqueous Wittig reaction as substrates. The scope of the aqueous Wittig reaction is extended to 24 examples of one-pot mixtures of Ph3P, α-bromoesters, and aldehydes in sodium bicarbonate solution (at 20°C for 40 min to 3 h) to provide Wittig products of up to 99% yield and up to 98% E-selectivity. Since water is inexpensive, extremely easy to handle, and represents no environmental concerns, it should be considered a possible medium for new organic reactions.
- El-Batta, Amer,Jiang, Changchun,Zhao, Wen,Anness, Robert,Cooksy, Andrew L.,Bergdahl, Mikael
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p. 5244 - 5259
(2008/02/07)
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- NOVEL COMPOUNDS THAT MODULATE PPARγ TYPE RECEPTORS, AND USE THEREOF IN COSMETIC OR PHARMACEUTICAL COMPOSITIONS
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The invention relates to novel compounds corresponding to the general formula (I) below: and also to the method for preparing them, and to their use in pharmaceutical compositions intended for use in human or veterinary medicine (in dermatology, and also
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Page/Page column 28-29
(2010/11/08)
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- Two variations of solvent-reduced wittig olefination reactions - Comparison of solventless wittig reactions to wittig reactions under ultrasonication with minimal work-up
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Stabilized and semi-stabilized phosphoranes can be subjected to solventless Wittig reactions with carbaldehydes. Simple heating of a mixture of added components at 100°C in an electric oven gives the corresponding olefins in good yield. Alternatively, the Wittig reactions can be carried out in a biphasic medium under ultrasonication. In this case, the Wittig products can be isolated by simple evaporation of the organic phase without additional work-up.
- Watanabe, Masataka,Morais, Goreti Ribeiro,Mataka, Shuntaro,Ideta, Keiko,Thiemann, Thies
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p. 909 - 915
(2007/10/03)
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- Water is an efficient medium for Wittig reactions employing stabilized ylides and aldehydes
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Water is demonstrated to be an excellent medium for the Wittig reaction employing stabilized ylides and aldehydes. Although the solubility in water appears to be an unimportant characteristic in achieving good chemical yields and E/Z-ratios, the rate of W
- Dambacher, Jesse,Zhao, Wen,El-Batta, Amer,Anness, Robert,Jiang, Changchun,Bergdahl, Mikael
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p. 4473 - 4477
(2007/10/03)
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- Anilide derivative, production and use thereof
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This invention is to provide a compound of the formula: wherein R1 is an optionally substituted 5- to 6-membered ring: C is a divalent group of the formula: wherein the ring A is an optionally substituted 5- to 6-membered aromatic ring, X is an optionally substituted C, N or O atom, and the ring B is an optionally substituted 5- to 7-membered ring; Z is a chemical bond or a divalent group; R2 is (1) an optionally substituted amino group in which a nitrogen atom may form a quaternary ammonium, etc., or a salt thereof, which is useful for antagonizing MCP-1 receptor.
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