- Nickel-Catalyzed Selective Reduction of Carboxylic Acids to Aldehydes
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The direct reduction of carboxylic acids to aldehydes is a fundamental transformation in organic synthesis. The combination of an air-stable Ni precatalyst, dimethyl dicarbonate as an activator, and silane reductant effects this reduction for a wide variety of substrates, including pharmaceutically relevant structures, in good yields and with no overreduction to alcohols. Moreover, this methodology is scalable, allows access to deuterated aldehydes, and is also compatible with one-pot utilization of the aldehyde products.
- Iosub, Andrei V.,Morav?ík, ?tefan,Wallentin, Carl-Johan,Bergman, Joakim
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supporting information
p. 7804 - 7808
(2019/10/14)
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- One-Pot Preparation of C1-Homologated Aliphatic Nitriles from Aldehydes through a Wittig Reaction under Metal-Cyanide-Free Conditions
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A one-pot protocol to obtain C1-homologated aliphatic nitriles was achieved by treating aromatic and aliphatic aldehydes with the (methoxymethyl)triphenylphosphonium ylide followed by hydrolysis of the resulting methyl vinyl ethers with pTsOH (Ts = para-toluenesulfonyl) and treatment with molecular iodine and aqueous ammonia under metal cyanide free conditions. Neopentyl-type nitriles, which could not be obtained by conventional methods that involved conversion of the neopentyl alcohol into a tosylate and treatment with metal cyanide, were successfully obtained by using the present method.
- Ezawa, Masatoshi,Togo, Hideo
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p. 2379 - 2384
(2017/05/01)
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- Synthesis of 2-tetralone derivatives by Bi(OTf)3-catalyzed intramolecular hydroarylation/isomerization of propargyl alcohols
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Compared to 1-tetralones, 2-tetralones are expensive, less stable, and difficult to synthesize. A concise Bi-catalyzed method was developed for the synthesis of 2-tetralones from 5-phenylpent-1-yn-3-ol derivatives. Diverse 2-tetralones were obtained in moderate to good yields under mild conditions.
- Yun, Jihee,Park, Jungmin,Kim, Jaehyun,Lee, Kooyeon
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p. 1045 - 1048
(2015/02/19)
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- Vinyl polymerization versus [1,3] O to C rearrangement in the ruthenium-catalyzed reactions of vinyl ethers with hydrosilanes
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Two reactions, vinyl polymerization and [1,3] O to C rearrangement of vinyl ethers, are investigated in the ruthenium-catalyzed reaction with hydrosilanes. The reaction pathways are dependent on the substituents of the vinyl ether, in particular, those of the alkoxy group. Primary-, secondary-, and tertiary-alkyl vinyl ethers, ROCHCH2, are polymerized with ease to give the corresponding polymer in good yields. When R is electron-donating benzyl groups, the reaction does not give the polyvinyl ether but results in [1,3] O to C rearrangement to give the corresponding aldehyde, RCH2CHO in moderate to good yields. The rearrangement selectively proceeds when vinyl ethers having α-substituents are used as the starting materials to give the corresponding ketones in high yields. With catalytic amounts of hydrosilanes, the rearrangement gives ketones or aldehydes selectively. In sharp contrast, use of excess amounts of hydrosilanes leads to the rearrangement followed by reduction of the formed carbonyl group to give the corresponding silyl ethers in good yields. Nature of catalytically active species is discussed. Crown Copyright
- Harada, Nari-Aki,Nishikata, Takashi,Nagashima, Hideo
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supporting information; experimental part
p. 3243 - 3252
(2012/06/01)
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- PROCESSES AND INTERMEDIATES FOR PREPARING CYSTEINE PROTEASE INHIBITORS
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The present invention is directed to a novel process for preparing certain cysteine protease inhibitors.
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Page/Page column 57
(2010/10/20)
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- HALOALKYL CONTAINING COMPOUNDS AS CYSTEINE PROTEASE INHIBITORS
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The present invention is directed to compounds that are inhibitors of cysteine proteases, in particular, cathepsins B, K, L, F, and S and are therefore useful in treating diseases mediated by these proteases. The present invention is directed to pharmaceutical compositions comprising these compounds and processes for preparing them.
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Page/Page column 57
(2008/06/13)
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- HALOALKYL CONTAINING COMPOUNDS AS CYSTEINE PROTEASE INHIBITORS
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The application is directed to haloalkyl-substituted compounds of Formula (I), wherein R1, R1a, R2, R3, R4’ and E are as defined in the claims. The compounds are inhibitors of cysteine proteases, in p
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Page/Page column 45
(2010/02/11)
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- AMIDINO COMPOUNDS AS CYSTEINE PROTEASE INHIBITORS
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The present invention is directed to compounds that are inhibitors of cysteine proteases, in particular, cathepsins B, K, L, F, and S and are therefore useful in treating diseases mediated by these proteases. The present invention is directed to pharmaceu
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Page/Page column 41
(2010/02/09)
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- CYSTEINE PROTEASE INHIBITORS
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The present invention is directed to compounds that are inhibitors of cysteine protease, in particular, cathepsins B, K, L, F, and S and are therefore useful in treating diseases mediated by these proteases. The present invention is directed to pharmaceut
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Page/Page column 45
(2010/02/07)
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- PEPTIDIC COMPOUNDS AS CYSTEINE PROTEASE INHIBITORS
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The present invention is directed to compounds that are inhibitors of cysteine proteases, in particular, cathepsins B, K, L, F, and S and are therefore useful in treating diseases mediated by these proteases. The present invention is directed to pharmaceutical compositions comprising these compounds and processes for preparing them.
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- Substituted guanidine derivatives and process for producing the same
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A compound represented by the general formula (1): wherein each of R1, R2, R3, R4and R5is a hydrogen atom, an alkyl group, a substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group, an aromatic group, an acyl group or the like; each of Y1, Y2, Y3and Y4is a single bond, —CH2—, —O—, —CO— or the like, provided that at least two of Y1through Y4are independently a group other than a single bond; and Z may be absent, or one or more Zs may be present and are independently an alkyl group, a substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group, a halogen atom, a carboxyl group, an alkoxycarbonyl group, an aromatic group, an acyl group or the like, is useful as a therapeutic or prophylactic agent for diseases caused by the acceleration of the sodium/proton exchange transport system.
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Page column 65-66
(2010/01/31)
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- Palladium(II)-catalyzed phenylation of unsaturated compounds using phenylantimony chlorides under air
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Diphenylantimony chloride and phenylantimony dichloride, mainly the former, react smoothly with alkenes in acetonitrile at r.t. in the presence of a catalytic amount of Pd(OAc)2 under air to afford the corresponding phenylated alkenes (Heck-type reaction). The addition of AgOAc as reoxidant is not necessary for this reaction in sharp contrast to similar reactions using triarylstibines. The oxygen absorption is confirmed in this catalytic reaction and the reaction does not proceed catalytically in palladium(II) under inert gases, such as nitrogen or argon. Even under air the addition of a radical scavenger stopped the reaction. The regeneration of PhPdOAc species from Ph2SbCl, HPdOAc species and oxygen is proposed as a key step in the catalytic cycle where oxygen-containing radical species might be present as intermediates.
- Matoba, Kazutaka,Motofusa, Shin-Ichi,Sik Cho, Chan,Ohe, Kouichi,Uemura, Sakae
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