- Synthesis of β-hydroxy esters using highly active manganese
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A modified Reformatsky reaction is reported using highly reactive manganese (Mn*). The active manganese was found to readily react with α-haloester in the presence of aldehydes and ketones to yield the corresponding β-hydroxy esters. The reaction is carried out at room temperature in the absence of Lewis acid or trapping agents.
- Suh, YoungSung,Rieke, Reuben D.
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- Photoredox Reaction of 2-Mercaptothiazolinium Salts with Silyl Enol Ethers
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A method for the generation of free radicals from thiazolinium salts upon photocatalytic reduction is described. The thiazolinium salts are generated by treatment with methyl triflate of 2-mercaptothiazolines, which can be readily obtained from alkyl bromides and tosylates via a nucleophilic substitution reaction or by hydrothiolation of alkenes. Silyl enol ethers were used to trap the radicals, furnishing ketones after successive single-electron oxidation and elimination of the silyl cation.
- Zemtsov, Artem A.,Ashirbaev, Salavat S.,Levin, Vitalij V.,Kokorekin, Vladimir A.,Korlyukov, Alexander A.,Dilman, Alexander D.
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- Indium-catalyzed synthesis of keto esters from cyclic 1,3-diketones and alcohols and application to the synthesis of seratrodast
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Esterification reactions from cyclic 1,3-diketones and alcohols are carried out in the presence of several Lewis acids. In particular, indium(III) triflate, In(OTf)3, iron(III) triflate, Fe-(OTf)3, copper(II) triflate, Cu(OTf)2, and silver(I) triflate, AgOTf, show high catalytic activities. These reactions proceed through the carbon-carbon bond cleavage by a retro-aldol reaction and were found to be highly regioselective even in the presence of other functional groups. This type of reaction can also be applied to the preparation of the keto esters during the synthesis of seratrodast, which is an antiasthmatic and eicosanoid antagonist.
- Kuninobu, Yoichiro,Kawata, Atsushi,Noborio, Taihei,Yamamoto, Syun-Ichi,Matsuki, Takashi,Takata, Kazumi,Takai, Kazuhiko
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experimental part
p. 941 - 945
(2010/07/07)
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- PYRROLOPYRIDAZINE DERIVATIVES
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The invention relates to compound of the formula (I) or its salt, in which R1, R2, R3 and R4 are as defined in the description, their use of as medicament, the process for their preparation and use for the treatment of PDE-IV or TNF-α mediated diseases.
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- Structurally simple trichostatin A-like straight chain hydroxamates as potent histone deacetylase inhibitors
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A series of new, structurally simple trichostatin A (TSA)-like straight chain hydroxamates were prepared and evaluated for their ability to inhibit partially purified human histone deacetylase 1 (HDAC-1). Some of these compounds such as 8m, 8n, 12, and 15
- Woo, Soon Hyung,Frechette, Sylvie,Khalil, Elie Abou,Bouchain, Giliane,Vaisburg, Arkadii,Bernstein, Naomy,Moradei, Oscar,Leit, Silvana,Allan, Martin,Fournel, Marielle,Trachy-Bourget, Marie-Claude,Li, Zuomei,Besterman, Jeffrey M.,Delorme, Daniel
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p. 2877 - 2885
(2007/10/03)
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- Quinones. 4. Novel eicosanoid antagonists: Synthesis and pharmacological evaluation
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A new series of ω-phenyl-ω-quinonylalkanoic acids and related compounds was synthesized. The compounds were tested for their inhibitory effects on U-44069-induced contraction of the rabbit aorta. (±)-7-(3,5,6-Trimethyl-1,4-benzoquinon-2-yl)-7-phenylheptanoic acid (4d) (AA-2414) with pA2 value of 8.28 was one of the most potent compounds. Compound 4d inhibited U-46619-induced contraction of the guinea pig lung (pA2 = 8.29) and U-44069-induced aggregation of the guinea pig platelet (IC50 = 3.5 x 10-7 M). Compound 4d displaced the binding of [3H]U-46619 to guinea pig platelets (IC50 = 7.4 x 10-9 M). Compound 4d also showed very potent inhibitory effects with an MED of 0.3 mg/kg (po) on U-46619-, LTD4-, PAF-, or IgG1-induced bronchoconstriction in guinea pigs. The enantiomers of 4d were prepared. The R-(+) isomer 8a was active in both in vitro and in vivo tests, but the S-(-) isomer 8b was much less active. We concluded that the antiasthmatic effects of 4d were based mainly on the TXA2 receptor antagonistic action. In addition, compound 4d showed potent inhibitory effects on PGD2-, PGF(2α)-, and 11-epi-PGF(2α)-induced contraction of the guinea pig tracheal strips. The diverse inhibitory effects might be expressed in terms of eicosanoid-antagonistic activity.
- Shiraishi,Kato,Terao,Ashida,Terashita,Kito
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p. 2214 - 2221
(2007/10/02)
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