- 1,4-Addition of diorganozincs to α,β-unsaturated ketones catalyzed by a copper(I)-sulfonamide combined system
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A mixture of CuCN and N-benzylbenzenesulfonamide catalyzes the 1,4- addition of dialkylzincs or diarylzincs (Cu: Zn = 1: 200 to 1: 10000) to α,β-unsaturated ketones to give, after aqueous workup, the corresponding β-substituted ketones in nearly quantitative yields. A range of cyclic enones having s-cis or s-trans geometries as well as conformationally flexible acyclic enones are usable as substrates. The ethyl group migrates more readily than the methyl and phenyl groups. CuOTf, CuO-t-C4H9, and mesitylcopper can be used in place of CuCN. The in situ-formed alkylzinc enolate, prior to aqueous workup, further undergoes an aldol reaction with aldehydes or Pd(0)-assisted coupling with allyl acetate, resulting in regio- controlled, vicinal carbacondensation products. A catalytic cycle is proposed on the basis of a kinetic study and a structural analysis of the zinc enolate product by NMR and molecular weight measurements.
- Kitamura, Masato,Miki, Takashi,Nakano, Keiji,Noyori, Ryoji
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- Serine carbonates
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Serine carbonates of formula I are precursors for organoleptic compounds, masking agents and antimicrobial agents. Further they are alternative substrates for malodor producing enzymes. The symbols in formula I are defined in claim 1.
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- Compounds having protected hydroxy groups
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The present invention relates to compounds with protected hydroxy groups of formula (I) These compounds are precursors for organoleptic agents, such as fragrances, and masking agents and for antimicrobial agents. When activated, the compounds of formula (I) are cleaved and form one or more organoleptic and/or antimicrobial compounds.
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- Compounds having protected hydroxy groups
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The present invention relates to compounds with protected hydroxy groups of formula (I) These compounds are precursors for organoleptic agents, such as fragrances, and masking agents and for antimicrobial agents. When activated, the compounds of formula (I) are cleaved and form one or more organoleptic and/or antimicrobial compounds.
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- Precursors for fragrant ketones and fragrant aldehydes
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The present invention refers to fragrance precursors of formula I for a fragrant ketone of formula II and one or more fragrant aldehydes or ketones of formula III and IV, These fragrance precursors are useful in perfumery, especially in the fine and functional perfumery.
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- Beta-ketoester compounds
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The beta-ketoesters of formula I are useful as precursors for organoleptic compounds, especially for flavors, fragrances and masking agents and antimicrobial compounds.
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- Ketone precursors for organoleptic compounds
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The invention discloses ketones of formula I: wherein, Y is an optionally substituted alkyl, cycloalkyl, or cycloalkylalkyl, wherein each alkyl group is straight or branched and each alkyl and cycloalkyl group is saturated or unsaturated; R1is hydrogen or a C1-6alkyl group that is substituted, saturated or unsaturated, straight or branched; A is a chromophoric substituted aromatic ring or ring system; n is an integer; and with the proviso that formula I is not 2-ethoxy-1-phenyl-ethanone. These compositions are useful for the delivery of organoleptic compounds, especially of flavors, fragrances, masking agents and antimicrobial compounds.
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- Amidino derivatives useful as nitric oxide synthase inhibitors
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The current invention discloses useful pharmaceutical compositions containing amidino derivative useful as nitric oxide synthase inhibitors.
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- Amidino dervatives useful as nitric oxide synthase inhibitors
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The current invention discloses useful pharmaceutical compositions containing azepine derivatives useful as nitric oxide synthase inhibitors.
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- Conjugate addition of diorganozincs to α,β-unsaturated ketones catalyzed by a copper(I)-sulfonamide combined system
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In the presence of a Cu(I)-N-monosubstituted sulfonamide combined catalyst system, diorganozincs react with α,β-unsaturated ketones to generate Zn enolates, which may be hydrolyzed, giving the β-substituted ketones, or used for further aldol reaction or Pd(O)-catalyzed reaction with allyl acetate leading to the regiospecific α,β-vicinal condensation products.
- Kitamura, Masato,Miki, Takashi,Nakano, Keiji,Noyori, Ryoji
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p. 5141 - 5144
(2007/10/03)
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