- The synthesis of methyl cyclopropylacetate by palladium(II) acetate catalysed reaction of diazomethane with vinyl group
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The methyl cyclopropylacetate was prepared in high yield by Palladium(II) acetate catalysed reaction of vinyl acetic acid with an excess of diazomethane. The cyclopropylacetonitrile was prepared from allyl cyanide by the same method.
- Basnak,Jurkovic,Basnakova
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- Free Radical Rearrangements in Uracil Derivatives
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As part of an effort to develop general probes for radical reactions involving DNA bases, several uracil derivatives were synthesized.The rates of the cyclopropyl carbinyl rearrangement in these systems were evaluated by means of competition experiments.The results indicate that when a cyclopropyl group is substituted in the 5-position of uracil, the rearrangement occurs very slowly - with a rate constant of -1.On the other hand, the analog of the 5-hexenyl radical cyclization onto the 5,6-double bond of uracil derivatives occurs with rates which were similar to the parent process: (4.0-8.9)E4 s-1.The experimental results along with semiempirical calculations show that radicals 23 and 25 are unusually stable species.These results explain why no rearrangements are observed when a cyclopropyl-substituted thymine dimer is cleaved by reductive single electron transfer.
- Fenick, David J.,Falvey, Daniel E.
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- Synthesis and biological evaluation of spirocyclic antagonists of CCR2 (chemokine CC receptor subtype 2)
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Activation of chemokine CC receptors subtype 2 (CCR2) plays an important role in chronic inflammatory processes such as atherosclerosis, multiple sclerosis and rheumatoid arthritis. A diverse set of spirocyclic butanamides 4 (N-benzyl-4-(3,4-dihydrospiro[[2]benzopyran-1,4′-piperidin]-1′-yl)butanamides) was prepared by different combination of spirocyclic piperidines 8 (3,4-dihydrospiro[[2]benzopyran-1,4′-piperidines]) and γ-halobutanamides 11. A key step in the synthesis of spirocyclic piperidines 8 was an Oxa-Pictet-Spengler reaction of β-phenylethanols 5 with piperidone acetal 6. The substituted γ-hydroxybutanamides 11c-e were prepared by hydroxyethylation of methyl acetates 13 with ethylene sulfate giving the γ-lactones 14c and 14e. Aminolysis of the γ-lactones 14c and 14e with benzylamines provided the γ-hydroxybutanamides 15c-e, which were converted into the bromides 11c-e by an Appel reaction using polymer-bound PPh3. In radioligand binding assays the spirocyclic butanamides 4 did not displace the iodinated radioligand 125I-CCL2 from the human CCR2. However, in the Ca2+-flux assay using human CCR2 strong antagonistic activity of butanamides 4 was detected. Analysis of the IC50-values led to clear relationships between the structure and the inhibition of the Ca2+-flux. 4g (4-(3,4-dihydrospiro[[2]benzopyran-1,4′-piperidin]-1′-yl)-N-[3,5-bis(trifluoromethylbenzyl)]-2-(4-fluorophenyl)butanamide) and 4o (N-[3,5-bis(trifluoromethyl)benzyl]-2-cyclopropyl-4-(3,4-dihydrospiro[[2]benzopyran-1,4′-piperidin]-1′-yl)butanamide) represent the most potent CCR2 antagonists with IC50-values of 89 and 17 nM, respectively. Micromolar activities were found in the β-arrestin recruitment assay with murine CCR2, but the structure-activity-relationships detected in the Ca2+-flux assay were confirmed.
- Strunz, Ann Kathrin,Zweemer, Annelien J.M.,Weiss, Christina,Schepmann, Dirk,Junker, Anna,Heitman, Laura H.,Koch, Michael,Wünsch, Bernhard
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p. 4034 - 4049
(2015/03/14)
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- Cerium-catalyzed α-hydroxylation reactions of α-cyclopropyl β-dicarbonyl compounds with molecular oxygen
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Three α-cyclopropyl β-dicarbonyl compounds have been used as probes for α-radicals as electrophilic reaction intermediates in a cerium-catalyzed α-hydroxylation reaction with molecular oxygen. Since the cyclopropyl group did not ring-open to products with a butenyl moiety, but was retained in the products, a localized unpaired electron at the α position can be excluded during the course of the reaction. The α-cyclopropyl- substituted substrates were prepared by aldol or Claisen reactions. Other substrates with α-methyl, α-isopropyl, and α-tert-butyl substituents were prepared and converted under the α-hydroxylation conditions in order to estimate steric influences on the yield of the reaction. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Christoffers, Jens,Kauf, Thomas,Werner, Thomas,Roessle, Michael
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p. 2601 - 2608
(2007/10/03)
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- DIHYDROIMIDAZOTHIAZOLE DERIVATIVES
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Compounds of formula (I): or pharmaceutically acceptable salts thereof, exhibit 5-HT1A agonism in addition to noradrenaline reuptake inhibition and optionally also 5-HT reuptake inhibition are useful for the treatment of obesity.
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Page/Page column 34
(2008/06/13)
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- 2-Ureido-thiazole derivatives, process for their preparation, and their use as antitumor agents
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Compounds which are 2-ureido-1,3-thiazole derivatives of formula (I) wherein R is a halogen atom, a nitro group, an optionally substituted amino group or it is a group, optionally further substituted, selected from: i) straight or branched C1-C6 alkyl; ii) C3-C6 cycloalkyl; iii) aryl or arylalkyl with from 1 to 6 carbon atoms within the straight or branched alkyl chain; R1 is an optionally substituted group selected from: i) straight or branched C1-C6 alkyl; ii) 3 to 6 membered carbocycle or 5 to 7 membered heterocycle ring, iii) aryl or arylcarbonyl; iv) arylalkyl with from 1 to 6 carbon atoms within the straight or branched alkyl chain: R2 is hydrogen, a straight or branched C1-C4 alkyl or C2-C4 alkenyl or alkynyl group; or, taken together with the nitrogen atom to which they are bonded, R1 and R2 form a substituted or unsubstituted group selected from: i) an optionally benzocondensed or bridged 5 to 7 membered heterocycle; or ii) a 9 to 11 membered spiro-heterocyclic compound; or a pharmaceutically acceptable salt thereof; are useful for treating cell proliferative disorders associated with an altered cell dependent kinase activity.
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