7448-87-5

A novel access to fused furan cores using silver oxide(I) has been developed. Mechanistic investigations indicate the involvement of a Conia-ene reaction/radical cyclization for an expedient path to complex furan derivatives. The reaction is broad in scop

A sequential and efficient protocol for the synthesis of α-thiolated enaminones has been developed using copper-TEMPO systems. This reaction features a broad substrate scope to afford the desired product in good to excellent yields with high stereoselectivity. A preliminary mechanistic study suggests that the in situ formed enaminone acts as the key intermediate.

We report mild new annulation approaches to trisubstituted trifluoromethylthiolated (SCF3) aziridines and cyclopropanes via Darzens inspired protocols. The products of these anionic annulations, rarely studied previously, possess attractive features rendering them valuable building blocks for synthesis platforms. In this study, trisubstituted acetophenone nucleophiles bearing SCF3 and bromine substituents in their α position were shown to undergo [2 + 1] annulations with vinyl ketones and tosyl-protected imines under mild reaction conditions.

The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease, the most important parasitic infection in Latin America. The only treatments currently available are nitro-derivative drugs that are characterised by high toxicity and limited efficacy. Therefore, there is an urgent need for more effective, less toxic therapeutic agents. We have previously identified the potential for Mannich base derivatives as novel inhibitors of this parasite. To further explore this family of compounds, we synthesised a panel of 69 new analogues, based on multi-parametric structure-activity relationships, which allowed optimization of both anti-parasitic activity, physicochemical parameters and ADME properties. Additionally, we optimized our in vitro screening approaches against all three developmental forms of the parasite, allowing us to discard the least effective and trypanostatic derivatives at an early stage. We ultimately identified derivative 3c, which demonstrated excellent trypanocidal properties, and a synergistic mode of action against trypomastigotes in combination with the reference drug benznidazole. Both its druggability and low-cost production make this derivative a promising candidate for the preclinical, in vivo assays of the Chagas disease drug-discovery pipeline.

A visible light photoredox-promoted and nitrogen radical catalyzed [3 + 2] cyclization of vinylcyclopropanes and N-tosyl vinylaziridines with alkenes is developed. Key to the success of this process is the use of the readily tunable hydrazone as a nitrogen radical catalyst. Preliminary mechanism studies suggest that the photogenerated nitrogen radical undergoes reversible radical addition to the vinylcyclopropanes and N-tosyl vinylaziridines to enable their ring-opening C-C and C-N bond cleavage and ensuing cyclization with alkenes.

The invention relates to a process for preparing an α-methylene ketone comprising the step of reacting a ketone with formaldehyde in the presence of a catalyst which is an organic compound comprising at least one acid function or the corresponding salt, ester or amide thereof and at least one amine function or the corresponding ammonium salt, or a zwitterion thereof.

The invention relates to new compounds of formulae (IV), wherein X represents a halogen atom selected from the group consisting of fluorine, chlorine, bromine and iodine, said compounds being useful as precursors and/or intermediates for the preparation of 4,4'dihalobenzophenones of formula (I), wherein X is as defined above.

Unprecedented direct access to terminal enones via α-methylenation of aryl ketones to form C=C bond is achieved under visible-light conditions using methanol as one carbon source substrate and solvent as well. The reaction involves Cu@g-C3N4-catalysed in situ oxidation of methanol into formaldehyde followed by dehydrative cross aldol type reaction. Various aryl ketones react efficiently with MeOH, producing α,β-unsaturated carbonyl compounds only in 4–8 h at room temperature in excellent yield (84–97%). Operational simplicity, wide substrate scope, ambient reaction conditions, visible-light photocatalysis and novel application of MeOH as methylene donor substrate are the salient features making the envisaged protocol mild, efficient and green alternative to the existing methods for synthesis of such fine chemicals. (Figure presented.).

We evaluated the influence of solvent on the alumina-promoted C3-alkylation of indoles with α,β-unsaturated ketones. We found that lipophilic solvents were generally superior to hydrophilic ones with hexanes offering the 3-alkyl indole products in high yields. Thus, we demonstrate an inexpensive and procedurally simple new process that pairs acidic alumina with hexanes to achieve this important Michael alkylation. The substrate scope includes twenty-four examples with reaction yields ranging from 61 to 96%. (Figure presented.).

A manganese-catalyzed ring-opening coupling reaction of cyclopropanols with enones for the facile and efficient preparation of 1,6-diketones is described. A wide array of synthetically important 1,6-diketones bearing manifold functional groups are obtained with up to 93% yield. These reactions feature broad substrate scopes, environmentally benign conditions, inexpensive catalyst, and operational simplicity.

In the presence of catalytic [RuCl2(p-cym)]2 and using Li3PO4 as the base, benzoic acids react with olefins in water to afford the corresponding 2-alkylbenzoic acids in moderate to excellent yields. This C?H alkylation process is generally applicable to diversely substituted electron-rich and electron-deficient benzoic acids, along with α,β-unsaturated olefins including unprotected acrylic acid. The widely available carboxylate directing group can be removed or utilized for further derivatization. Mechanistic investigations revealed that the transformation proceeds via a ruthenacycle intermediate.

The kinetics and mechanism of the thermally activated dynamic covalent exchange of thiol-Michael adducts is investigated. A model system of thiol-Michael adducts between thiophenol and phenylvinylketone derivatives and adducts between 2-mercaptoethanol phenylvinylketone derivatives in N,N-dimethylformamide (DMF) at elevated temperatures is used to probe the underlying exchange mechanism. The kinetic data show negligible free Michael acceptor, which is consistent with the highly efficient thiol-Michael reaction being a "click"-like reaction that significantly favors the adduct form. At elevated temperatures of 90 °C in DMF the thiol-Michael adducts reach equilibrium after 24 h, although equilibration did not occur within 24 h at 60 °C or 75 °C, and negligible exchange occurs under ambient conditions. A kinetic model was developed to describe the dynamic covalent exchange and equilibration. The experimental and simulation kinetic data of dynamic covalent exchange are consistent with the thiol-Michael adducts undergoing a retro-Michael reaction, followed by subsequent addition of a free thiol to the liberated Michael acceptor. Kinetic analysis is consistent with the fragmentation, or retro-Michael reaction, being the rate-determining step in the dynamic covalent exchange. This suggests that the key step in dynamic covalent exchange is not enhanced by addition of free thiol or free Michael acceptor, since the addition reaction is much faster than the retro-Michael reaction. This fundamental study will guide the design of organic compounds, materials, and bioconjugates that utilize the thermally activated dynamic covalent thiol-Michael linkages.

The invention discloses a method for synthesizing an alpha,beta-unsaturated aryl ketone compound from dimethyl sulfoxide and arylethanone. According to the method, dimethyl sulfoxide and arylethanoneare subjected to a one-pot reaction in the presence of carboxylate and persulfate so as to produce the alpha,beta-unsaturated aryl ketone compound. The method uses dimethyl sulfoxide as a methylenation reagent and employs a one-pot process for high-selectivity high-yield synthesis of the alpha,beta-unsaturated aryl ketone compound from arylethanone; and the method is simple to operate, low in cost, friendly to environment and beneficial for industrial production.

The invention discloses a method for synthesizing alpha,beta-unsaturated ketone compounds from dimethyl sulfoxide and ketone compounds. According to the method, dimethyl sulfoxide and ketone compoundsare subjected to a one-pot reaction in the presence of carboxylate and persulfate so as to produce the alpha,beta-unsaturated ketone compounds. The method uses dimethyl sulfoxide as a methylenation reagent and employs a one-pot process for high-selectivity high-yield synthesis of the alpha,beta-unsaturated ketone compounds from the ketone compounds; and the method is simple to operate, low in cost, friendly to environment and beneficial for industrial production.

The hydration of α,β-unsaturated ketones with water proceeded efficiently in the presence of In(OTf)3 (20 mol%) in aqueous media to afford synthetically versatile β-hydroxyketones in moderate to good yields with good functional group compatibility. The method also can be extended to the hydroalkoxylation of α,β-unsaturated ketones with various alcohols for the efficient synthesis of β-alkoxyketones as well as tetrahydrofuran derivatives. (Figure presented.).

A readily available and bench-stable cyanomethyl sulfonium salt was used in highly diastereoselective Corey-Chaykovsky cyclopropanation reactions of electron-poor olefins. This efficient method provides a rapid route to access densely functionalized cyclopropyl nitriles.

An efficient chromium(III) chloride-catalyzed Michael-type reaction of water or alcohol with α,β-unsaturated ketones is developed. A variety of α,β-unsaturated ketones effectively reacted with either water or alcohols to give the corresponding β-hydroxyl ketones or β-alkoxyl ketones in modest to high yields with excellent compatibility to various functional groups. The approach was further utilized for the preparation of synthetically useful compounds containing tetrahydrofuran skeleton.

An organo-catalyzed enantioselective addition of selenosulfonates to α,β-unsaturated ketones was developed for the first time. With a chiral squaramide as an efficient catalyst, the desired α-selenylated ketones were obtained in a good yields with high enantioselectivity up to 89% ee, and good results could be obtained on a gram scale. The products could also be efficiently transformed into useful building blocks with a propenylic stereocenter; the strategy presented in this study may find further applications in organic synthesis.

A direct α-Csp3-H methylenation of arylketones to form C=C bond using dimethyl sulfoxide as one-carbon source is achieved under transition metal-free reaction condition. Various aryl ketone derivatives react readily with DMSO, producing the α,β-unsaturated carbonyl compounds in yields of 42 to 90%. This method features a transition metal-free reaction condition, wide substrate scope and using DMSO as novel one-carbon source to form C=C bond, thus providing an efficient and expeditious approach to an important class of α,β-unsaturated carbonyl compounds. Based on the preliminary experiments, a plausible mechanism of this transformation is disclosed.

A divergent synthesis of optically active quaternary Δ4- and Δ5-dehydro prolines is developed based on the first catalytic enantioselective conjugate addition of α-substituted isocyano(thio)acetates to vinyl ketones that is general for both α-aryl and α-alkyl isocyano(thio)acetates. The new tetrasubstituted C?N stereocenter is formed without the need of any metal salt due to a bifunctional tertiary amine/squaramide catalyst, featuring a bulky polyaryl sidearm and an unusually short squaramide diamide H???H interatomic distance in the solid state.

The invention discloses a fluorine-containing three-membered ring compound shown in the formula V-a, V-b or V-c and a preparation method thereof. The preparation method comprises that in an organic solvent, fluoroalkyl sulfur ylide shown in the formula II

An intermolecular Morita-Baylis-Hillman (MBH) reaction of α,β-unsaturated ketones with allylic acetates under the catalysis of 10 mol % of tetrakis(triphenylphosphine)palladium(0) and mediation of tributylphosphine has been developed in the presence of acetic acid, affording the desired α-coupling products. The MBH reaction has the advantages of good tolerance to many functional groups, excellent regioselectivity and E-stereoselectivity, and moderate to good yields.

(2,2,2-Trifluoroethyl)diphenylsulfonium triflate was found to be an efficient ylide reagent for the Johnson-Corey-Chaykovsky reaction to afford trifluoromethyl epoxides, cyclopropanes and aziridines. Interestingly, excellent but different diastereoselectivity was observed for these transformations. Both trifluoromethyl epoxides and cyclopropanes were obtained with trans-selectivity, whereas aziridines were obtained with cis-selectivity.

Pyruvate kinase M2 (PKM2) is a key protein responsible for cancer's Warburg effect. Activation of PKM2 may alter aberrant metabolism in cancer cells, which suggests PKM2 as a tumor selective therapeutic target. In this paper, the lead compound 8 was first discovered as a new kind of PKM2 activator from a random screening of an in-house compound library. Then, a series of lead compound 8 analogs were designed, synthesized and evaluated for their activation of PKM2 and anticancer activities. 7-Azaindole analog 32 was identified as the most potent PKM2 activator. Compounds with potent enzyme activity also exhibited selective anti-proliferation activity on cancer cell lines HCT116, Hela and H1299 compared with non-tumor cell line BEAS-2B. The structure-activity relationships of these compounds were supported by molecular docking results. Preliminary pharmacological studies also showed that compound 32 arrests the cell cycle at the G2/M phase in HCT116 cell line.

A novel difunctionalization reaction is described. It uses N-trifluoromethylthio-4-nitrophthalimide as the reagent, which serves as both the nitrogen and SCF3 sources. In the presence of DABCO (1,4-diazabicyclo[2.2.2]octane), the nitrogen and SCF3 groups can be incorporated into α,β-unsaturated carbonyl compounds easily and give versatile β-amino ketones and esters in good yields. This difunctionalization reaction features mild reaction conditions, high atom-economy, and efficient access to α-SCF3 amino acids.

A one-step strategy for the synthesis of α-methenyl ketones from β-keto sufones is reported. Success of the methodology is elaborated for the synthesis of chromanones and isoflavanones in one-step.

An efficient Michael addition of alcohols to activated alkenes promoted by sodium carbonate with water as reaction medium has been developed. The reaction provides a general, economical and environmentally friendly approach for the synthesis of β-alkoxycarbonyl compounds.

Boron trihalide-promoted ring-opening reactions of gem-difluorocyclopropyl ketones to give the corresponding β-trifluoromethyl ketones and β-halodifluoromethyl ketones were described. It was found that boron trihalides act as both Lewis acids and nucleophiles and the proximal bond prefers to cleave in this transformation.

Thiazolium carbene-catalyzed reaction of aromatic 1,2-diketones with enones in aprotic solvents gave double acylation products in good yields, whereas hydroacylation products formed by Stetter reaction were not detected at all. These results suggested the generation of aroyloxyenamine species from the 1,2-diketones instead of hydroxyenamines (Breslow intermediates). This journal is

Using oxygen as the sole oxidant for two steps, we developed a new method to synthesize β-aryl α,β-enones by fine-tuning the Pd(ii)-catalyzed oxidation of allyl alcohol to subsequent arylation with arylboronic acids, arylboronic ester and aryltrifluoroborate salt. This one-pot green method does not require copper salt, base, and intermediate isolation. Halogen-bearing chalcones, dibenzylideneacetones and arylalkyl enones were synthesized in good yields. This journal is

The present application relates to novel 3-phenylpropionic acid derivatives which carry a branched or cyclic alkyl substituent in the 3-position, to processes for their preparation, to their use for the treatment and/or prevention of diseases and to their use for preparing medicaments for the treatment and/or prevention of diseases, in particular for the treatment and/or prevention of cardiovascular diseases.

A new strategy for the synthesis of vinyl ketones has been achieved. Hitherto unknown and easily accessible, β-phenylseleno-N-methoxy-N- methylpropanamide, obtained through two simple reactions, served as a building block for convenient access to vinyl ketones. The N-methoxy-N-methyl amide moiety ensured no overaddition of the Grignard reagent and, hence, the excellent formation of β-phenylseleno ketones; oxidative work-up with hydrogen peroxide provided ready access to the vinyl ketones with concomitant loss of phenylselanol. Georg Thieme Verlag Stuttgart · New York.

The present invention relates to compositions, for example, the DBU/Hexafluoroacetone hydrate salt, and processes of preparing and using the same for the modification of chemical compounds via the release of trifluoroacetate. The DBU/Hexafluoroacetone hydrate salt can perform trifluoromethylation reactions on chemical compounds, such as carbonyl group-containing compounds.

The present invention relates to: a ketone compound having transglutaminase-inhibiting activity, which is represented by the following Formula 1, 2, or 3: wherein R1 is a substituted or unsubstituted aryl or heterocyclyl group, R2, R3, and R4 are hydrogen atoms, n is 2, X is halogen, R5 and R6 independently represent a hydrogen atom or a substituted or unsubstituted C1-C10 alkyl, aryl, or aralkyl group, wherein R5 and R6 are not hydrogen atoms at the same time, or R5 and R6 may be taken together to form a saturated or unsaturated and substituted or unsubstituted heterocyclyl group containing a nitrogen atom (N); an inhibitor of protein crosslinking comprising the compound; and a composition for preventing or treating a protein-crosslinking causative disease, which comprises the compound or the protein crosslinking inhibitor.

The intramolecular acid catalyzed aldol cyclization of 2,3,7-triketoesters formed from Χ-keto-α-diazo-β-ketoesters provides highly functionalized cyclopentanones with good diastereoselectivity in high overall yields via kinetically controlled and stereodivergent catalytic processes. Lewis acid catalysis gives high selectivity for the 1,2-anti tetrasubstituted cyclopentanones, whereas Bronsted acid catalysis produces the corresponding 1,2-syn diastereomer.

A ruthenium trichloride complex has been loaded into an aluminium metal-organic framework (MOF), MOF-253, by post-synthetic modification to give MOF-253-Ru. MOF-253 contains open bipyridine sites that are available to bind with the ruthenium complex. MOF-253-Ru was characterised by elemental analysis, N2 sorption and X-ray powder diffraction. This is the first time that a Ru complex has been coordinated to a MOF through post-synthetic modification and used as a heterogeneous catalyst. MOF-253-Ru catalysed the oxidation of primary and secondary alcohols, including allylic alcohols, with PhI(OAc) 2 as the oxidant under very mild reaction conditions (ambient temperature to 40 C). High conversions (up to >99 %) were achieved in short reaction times (1-3 h) by using low catalyst loadings (0.5 mol % Ru). In addition, high selectivities (>90 %) for aldehydes were obtained at room temperature. MOF-253-Ru can be recycled up to six times with only a moderate decrease in substrate conversion. In the frame: A ruthenium trichloride complex is loaded into an aluminium metal-organic framework by post-synthetic modification (see figure). This material is used in the heterogeneous catalysis of the oxidation of primary and secondary alcohols, including allylic alcohols, with PhI(OAc)2 as the oxidant under mild reaction conditions. High selectivities for aldehydes are obtained at room temperature. Copyright

An efficient method for the α-methylenation of carbonyl groups is reported, and this transformation is accomplished by a facile elimination of trifluoroacetate during the formation of the olefin. This method represents an improvement beyond existing protocol in cases of steric hindrance, and we have demonstrated the utility of the process across a series of ketones, lactams, and lactones. Additionally, we have applied this method to produce semisynthetic derivatives of the natural products (+)-sclareolide and (-)-eburnamonine, in which the carbonyl group is proximal to bulky functional groups. Mechanistic insight is also provided from a time course of 19F NMR. Biological evaluation of the natural-product-derived enones led to the identification of a derivative of (-)-eburnamonine with significant cytotoxicity (LC50 = 14.12 ?M) in drug-resistant MDA-MB-231 breast cancer cells.

Bi(OTf)3 was proven to act as an effective catalyst for tandem ene-reaction/hydroamination of amino-olefin and amino-allene compounds with some enophiles, giving rise to functionalized N-heterocycles in good yields.

The scope of the novel ruthenium-catalyzed tandem cross-metathesis/ intramolecular-hydroarylation sequence is described. This methodology offers a practical and efficient synthesis of structurally diverse and complex tetrahydrocarbazoles in good to excellent yields (up to 98%). Moreover, preliminary efforts towards the development of an enantioselective version of the current process by sequential catalysis with ruthenium complex and chiral amine are presented, with high yields and enantioselectivities (up to 88% yield and 91% ee).

The first water-tolerant, ketone-type indium homoenolate was synthesized via the oxidative addition of In/InCl3 to enones. The reaction proceeds exclusively in aqueous media. Both indium and indium(III) chloride are necessary for the smooth conversion of the reaction. Similar results were obtained when InCl or InCl2 was used in place of In/InCl3. The synthetic utility of the indium homoenolate was demonstrated through the synthesis of 1,4-dicarbonyl compounds via palladium-catalyzed coupling of indium homoenolate with acid chloride.

The carbonylative cross-coupling of potassium vinyl trifluoroborate or 2,4,6-trivinyltricycloboroxane with aryl iodides under mild conditions affords aryl vinyl ketones. The optimisation of the reaction conditions leads to the targeted enones in good yiel

The reaction between 2′,4′-dihydroxyacetophenone and methyl vinyl ketone catalyzed by CaCl2/KOH in aqueous methanol yielded a 1,4-adduct, which was cyclized to 3,4-dihydro-2H-benzopyran (4) by acidic treatment. Analogous reaction using α, β-unsaturated aldehydes afforded benzopyrans (4) or (5) in a one-pot reaction. This method was successfully applied to the synthesis of β-tubaic acid (6), an antimicrobial 2H-1-benzopyran-6-carboxylic acid.

The synthesis and SAR of a novel series of non-nucleoside pyridopyrimidine inhibitors of the enzyme adenosine kinase (AK) are described. It was found that pyridopyrimidines with a broad range of medium and large non-polar substituents at the 5-position potently inhibited AK activity. A narrower range of analogues was capable of potently inhibiting adenosine phosphorylation in intact cells indicating an enhanced ability of these analogues to penetrate cell membranes. Potent AK inhibitors were found to effectively reduce nociception in animal models of thermal hyperalgesia and persistent pain. (C) 2000 Elsevier Science Ltd.

The kinetics of the reaction of substituted β-chloropropiophenones (RC6H4COCH2CH2Cl) and their α,α-deuterated analogs (RC6H4COCD2CH2Cl) with a series of amines in acetonitrile at 25 deg C were studied.It was shown that the relationships between the kinetic isotope effect H/kD)> and the pKa values of the amines for the substituted β-chloropropiophenones pass through a maximum and have various curvatures.The obtained dependence of kH/kD on the nature of the substituent in the substrate (?0) has complicated nonlinear character.Possible reasons for such relationships are discussed.

(η3-1- and 2-Trimethylsiloxyallyl)Fe(CO)2NO complexes were prepared by the reaction of the corresponding siloxyallylic halides with Bu4N.These complexes reacted with both of carbon nucleophiles and carbon electrophiles preferentially at the less hindered sites of the allylic ligands.In these reactions, (η3-1-trimethylsiloxyallyl)Fe(CO)2NO complexes served as synthetically equivalent synthons for both of β-acyl carbocations and β-acyl carbanions and (η3-2-trimethylsiloxyallyl)Fe(CO)2NO complexes as both of α-acyl carbocations and α-acyl carbanions.The stereochemical courses of the reactions are described.

1H-1,2,4-Triazol-yl-propan-3-ones were synthesized regioselectively using a modified Mannich reaction.Reactions of enones and Mannich bases with imidazole are also described.

The dependence of the formation rate of aryl vinyl ketones in the reaction of ring-substituted β-halogenopropiophenones with various amines on the structure of the reagents was investigated.By analysis of the obtained data it was concluded that the process takes place by an E2 mechanism through an anion-like transition state.

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