- Selective hydrogenation of benzoic acid to cyclohexane carboxylic acid over microwave-activated Ni/carbon catalysts
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High yields of cyclohexane carboxylic acids were obtained by direct hydrogenation of aromatic carboxylic acids over different Ni/carbon catalysts having distinctive surface properties. The catalysts were characterized by SEM, TEM, H2-TPR and N2 adsorption isotherms for the determination of BET surface area and porosity. The hydrogenation reaction was carried out in batch pressure reactor in gas-liquid phase at 200 °C. High selectivity (100%) of cyclohexane carboxylic acids at 86.2 mol% conversion of benzoic acid was achieved over microwave-activated biochar supported non-precious metal Ni catalyst. The 10%Ni/CSC-b catalyst has been investigated for hydrogenation of benzoic acid to cyclohexane carboxylic acids and shown little deactivation in stability test. The effects of Ni loading, high dispersion of Ni species, appropriate power of microwave heating and strong interaction of Ni species with carbon are of benefit to the reaction.
- Lu,Shen,He,Jing,Tao,Hu,Nie,Zhou,Xia
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- BICYCLIC NITROGENATED HETEROCYCLIC COMPOUND
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The present invention provides: a novel use of a specific bicyclic nitrogen-containing heterocyclic compound as a PDE7 inhibitor; a novel bicyclic nitrogen-containing heterocyclic compound having a PDE7 inhibitory effect, a method for producing the compound, a use of the compound, and a pharmaceutical composition containing the PDE7 inhibitor or the compound; and others. More specifically, the present invention provides a PDE7 inhibitor containing the compound represented by the formula (I): [wherein the symbols have the same meanings as those described in the description] or a pharmaceutically acceptable salt thereof as an active ingredient.
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Paragraph 1864; 1865; 1866
(2019/07/03)
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- Catalytic hydrogenation products of aromatic and aliphatic dicarboxylic acids
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Hydrogenation of aromatic dicarboxylic acids gave 100 % selectivity to respective cyclohexane dicarboxylic acid with 5 % Pd/C catalyst. 5 % Ru/C catalyst was observed to give over hydrogenation products at 493 K and at lower temperature (453 K) the selectivity for cyclohexane dicarboxylic acids was increased. Hydrogenation of phthalic acid with Ru-Sn/Al2O3 catalyst was observed to give phthalide instead of 1,2-benzene dimethanol or 2-hydroxy methyl benzoic acid. Ru-Sn/Al2O3 catalyst selectively hydrogenated the carboxylic group of cyclohexane dicarboxylic acids to give cyclohexane dimethanol. Use of proper catalysts and reaction conditions resulted in desired products.
- Shinde, Sunil B.,Deshpande, Raj M.
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p. 1137 - 1142
(2019/04/05)
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- ANTIALLERGY AND ANTIINFLAMMATORY BENZOXAZOLINONES
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This invention relates to certain benzoxazolinones which inhibit lipoxygenase and/or cyclooxygenase enzymes. Such compounds are useful in inhibiting such enzymes, per se, and are useful in treating allergic and inflammatory conditions in a mammal. This in
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- Antiparasitic agents
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The invention provides novel compounds having the formula: STR1 wherein R when taken individually is H; R1 when taken individually is H or OH; R and R1 when taken together represent a double bond; R2 is an alpha-branched C3 -C8 alkyl, alkenyl, alkynyl, alkoxyalkyl or alkylthioalkyl group; a C3 -C8 cycloalkyl, C5 -C8 cycloalkenyl or C5 -C8 cycloalkylalkyl group, any of which may be substituted by methylene or one or more C1 -C4 alkyl groups or halo atoms; or a 3 to 6 membered oxygen or sulphur containing heterocyclic ring which may be substituted by one or more C1 -C4 alkyl groups or halo atoms; R3 is hydrogen or methyl; R4 is H or 4'-(alpha-L-oleandrosyl)-alpha-L-oleandrosyloxy with the proviso that when R2 is alkyl it is not isopropyl or sec-butyl; when R4 is H, each of R and R1 is H, and R2 is not methyl or ethyl; and when R4 is H, R is H, R1 is OH, and R2 is not 2-buten-2-yl, 2-penten-2-yl or 4-methyl-2-penten-2-yl. The compounds are broad spectrum antiparasitic agents having utility as anthelmintics, ectoparasiticides, insecticides and acaricides. The invention also provides a process for producing the novel avermectin and milbemycin derivatives by adding a carboxylic acid or derivative thereof to a fermentation of an avermectin or milbemycin producing organism.
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- Pd-Catalyzed Regio- and Stereo-selective Carboxylation of Cycloalkanes with CO
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The reactions of cycloalkanes with CO via the C-H bond activation by Pd(OAc)2 catalyst have been found to proceed regio- and stereo-selectively to give corresponding carboxylic acids.The reactivity of C-H bonds of cycloalkanes decreases in the order: tert- > sec- > prim-carbon, and the stereochemistry of the substitutents on the main products is all equatorial.
- Satoh, Ko-ichi,Watanabe, Jun,Takaki, Ken,Fujiwara, Yuzo
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p. 1433 - 1436
(2007/10/02)
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- STEREOCHEMICAL CONTROL BY CARBOXYLATE GROUPS IN HOMOGENEOUS HYDROGENATION
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The stereochemistry of hydrogenation of a range of unsaturated cyclohexane-carboxylic acids and their esters has been investigated, employing either bis(1,4-diphenylphosphino)butanerhodium or pyridine(tricyclohexylphosphine)iridium based cationic catalysts in CH2Cl2.For methyl 3-methylcyclohex-2-enecarboxylate, highly selective reduction to the trans-product was achieved in both cases, whereas the isomeric methyl 3-methylenecyclohexanecarboxylate gave appreciable amounts of the cis-isomer.A predominance of trans-isomer was also achieved in the reduction of methyl 4-methylcyclohex-3-ene carboxylate, in a rather slower reaction.Reductions with D2 revealed that considerable isomerisation of the olefinic double bond occurred during hydrogenation.The corresponding unsaturated acids were reduced with moderate to high selectivity but reaction was either very slow, or ceased after a few turnovers.Related cyclohexadienecarboxylates were unreactive to homogeneous hydrogenation with cationic catalysts.
- Brown, John M.,Hall, Stephen A.
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p. 333 - 342
(2007/10/02)
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- Stereochemistry of Decarbalkoxylation of Cyclic Geminal Diesters Effected by Water and Lithium Chloride in Me2SO
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The stereochemical consequences of the decarbalkoxylation of cyclic geminal diesters by LiCl-H2O-Me2SO have been examined.The norbornene diester 13 and the norbornane diester 16 lead predominantly to the exoesters 14 and 17, respectively.The 2-methylcyclohexane diester 22 leads to esters containing more cis (23) than trans (24) isomer.The diesters 19,25, and 28 lead to nearly equal amounts of the cis and trans esters.In these latter cases,the enolates generated from the esters (via LDA) are protonated in a nonstereoselective fashion on quenching with water.This is suggestive of an enolate intermediate in the decarbalkoxylation reaction.The implications of these sterochemical results are discussed.
- Krapcho, A. Paul,Weimaster, John F.
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p. 4105 - 4111
(2007/10/02)
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- Stereochemistry of Alkylation of Carboxylic Acid Salt and Ester α Anions Derived from Cyclic Systems.
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A stereochemical study of the alkylation of α-lithiated carboxylate salts and esters has been performed.The α anions derived from the bicyclic acids exo-1, endo-1, and 7 (R=H) and the esters 4 and 7 (R=CH3) yield predominantly exo alkylation.As an example, the α anion derived from ester 7 (R=CH3) on treatment with CH3I yields exo-8 (R=R'=CH3) and endo-9 (R=R'=CH3) in a 97:3 ratio, a highly stereoselective reaction.Addition of TMEDA to the reactions involving the α anions derived from exo- or endo-1 did not change the stereochemical alkylation results.The α anions derived from the substituted cyclohexanecarboxylic acids 10, 13, 16, 19, or 22 (where R=H in each case) on methylation yield more axial methylation (axial/equatorial ratios of 0.4-2.7) than the α anions derived from the methyl esters corresponding to these acids.The α anions from the esters yield predominantly equatorial methylated products (e/a ratios varying from 4 to 9).The reasons for the different stereochemical results are discussed.
- Krapcho, A.Paul,Dundulis, Edward A.
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p. 3236 - 3245
(2007/10/02)
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