- Visible-Light Photocatalytic Preparation of 1,4-Ketoaldehydes and 1,4-Diketones from α-Bromoketones and Alkyl Enol Ethers
-
A Ru2+-photocatalyzed, visible-light-mediated ATRA reaction for the straightforward preparation of 1,4-ketoaldehydes, 1,4-diketones, and 1,4-ketoesters, which are of difficult access by other means, is reported herein. This method employs readily accessible α-bromoketones and alkyl vinyl ethers as starting materials, allowing the construction of secondary, tertiary, and challenging quaternary centers. In addition, the synthetic usefulness of this method is illustrated by applying it to the construction of substituted pyrroles.
- García-Santos, William H.,Mateus-Ruiz, Jeferson B.,Cordero-Vargas, Alejandro
-
supporting information
p. 4092 - 4096
(2019/06/17)
-
- Copper-Catalyzed Decarboxylative Oxyalkylation of Alkynyl Carboxylic Acids: Synthesis of ?-Diketones and ?-Ketonitriles
-
A novel copper-catalyzed decarboxylative oxyalkylation of alkynyl carboxylic acids with ketones and alkylnitriles via direct C(sp3)-H bond functionalization to construct new C-C bonds and C-O double bonds was developed. This transformation is featured by wide functional group compatibility and the use of readily available reagents, thus affording a general approach to ?-diketones and ?-ketonitriles. A possible mechanism is proposed.
- Li, Yi,Shang, Jia-Qi,Wang, Xiang-Xiang,Xia, Wen-Jin,Yang, Tao,Xin, Yangchun,Li, Ya-Min
-
supporting information
p. 2227 - 2230
(2019/03/26)
-
- Nonclassical Mechanism in the Cyclodehydration of Diols Catalyzed by a Bifunctional Iridium Complex
-
1,4- and 1,5-diols undergo cyclodehydration upon treatment with cationic N-heterocyclic carbene (NHC)–IrIII complexes to give tetrahydrofurans and tetrahydropyrans, respectively. The mechanism was investigated, and a metal-hydride-driven pathway was proposed for all substrates, except for very electron-rich ones. This contrasts with the well-established classical pathways that involve nucleophilic substitution.
- González Miera, Greco,Bermejo López, Aitor,Martínez-Castro, Elisa,Norrby, Per-Ola,Martín-Matute, Belén
-
supporting information
p. 2631 - 2636
(2019/02/01)
-
- One-pot synthesis of 2-methyl-1,5-diaromatic-1H-pyrroles from styrene, acetone and arylamines using TBHP, copper(II) trifluoromethanesulfonate and sulfamic acid
-
The one-pot copper/manganese co-catalyzed heterocyclization of arylamine derivatives with styrene and acetone to produce a series of 2-methyl-1,5-diaromatic-1H-pyrroles was investigated. The described reaction combines 1,4-dicarbonyl synthesis and Paal-Knorr type condensation reactions.
- Xu, Congjun,Han, Yufei,Chen, Shaowei,Xu, Dengzhi,Zhang, Bingfu,Shan, Zhenliang,Du, Shimei,Xu, Liying,Gong, Ping
-
p. 260 - 263
(2017/12/29)
-
- Light-Driven Vitamin B12-Catalysed Generation of Acyl Radicals from 2-S-Pyridyl Thioesters
-
Acyl radicals are invaluable intermediates in organic synthesis, however their generation remains challenging. Herein, we present an unprecedented light-driven, cobalt-catalysed method for the generation of acyl radicals from readily available 2-S-pyridyl thioesters. The synthetic potential of this methodology was demonstrated in the Giese-type acylation of activated olefins in the presence of heptamethyl cobyrrinate. This vitamin B12 derivative proved to be the most efficient catalyst in the studied process. The developed method features broad substrate scope (38 examples), good functional group tolerance, and mild reaction conditions. Moreover, it is easily scalable (illustrated on a 20-fold scale-up procedure), enabling its preparative use. Mechanistic studies revealed that the reaction proceeds via a radical pathway with the key steps involving the formation of an acyl-vitamin B12 complex and subsequent photolysis of the Co?C bond. (Figure presented.).
- Ociepa, Micha?,Baka, Oskar,Narodowiec, Jakub,Gryko, Dorota
-
supporting information
p. 3560 - 3565
(2017/10/24)
-
- Palladium-Catalyzed Room-Temperature Acylative Suzuki Coupling of High-Order Aryl Borons with Carboxylic Acids
-
This note describes a dimethyl dicarbonate-assisted, Pd(OAc)2/PPh3-catalyzed acylative Suzuki coupling of carboxylic acids with diarylborinic acids or tetraarylboronates for practical and efficient synthesis of sterically undemanding aryl ketones at room temperature. More than just cost-effective alternatives to aryl boronic acids, diarylborinic acids and tetraarylboronates displayed higher reactivity in the acylative Suzuki coupling. A variety of alkyl aryl ketones, including those bearing a hydroxy, bromo, or carbonyl group, could be readily obtained in modest to excellent yields.
- Si, Shufen,Wang, Chen,Zhang, Nan,Zou, Gang
-
p. 4364 - 4370
(2016/06/09)
-
- Copper/Manganese Cocatalyzed Oxidative Coupling of Vinylarenes with Ketones
-
A novel copper/manganese cocatalyzed direct oxidative coupling of terminal vinylarenes with ketones via C(sp3)-H bond functionalization following C-C bond formation has been developed using tert-butyl hydroperoxide as the radical initiator. Various ketones underwent a free-radical addition of terminal vinylarenes to give the corresponding 1,4-dicarbonyl products with excellent regioselectivity and efficiency through one step. A possible reaction mechanism has been proposed.
- Lan, Xing-Wang,Wang, Nai-Xing,Zhang, Wei,Wen, Jia-Long,Bai, Cui-Bing,Xing, Yalan,Li, Yi-He
-
supporting information
p. 4460 - 4463
(2015/09/28)
-
- A regio- and stereoselective ω-transaminase/monoamine oxidase cascade for the synthesis of chiral 2,5-disubstituted pyrrolidines
-
Biocatalytic approaches to the synthesis of optically pure chiral amines, starting from simple achiral building blocks, are highly desirable because such motifs are present in a wide variety of important natural products and pharmaceutical compounds. Herein, a novel one-pot ω-transaminase (TA)/monoamine oxidase (MAO-N) cascade process for the synthesis of chiral 2,5-disubstituted pyrrolidines is reported. The reactions proceeded with excellent enantio- and diastereoselectivity (>94 % ee; >98 % de) and can be performed on a preparative scale. This methodology exploits the complementary regio- and stereoselectivity displayed by both enzymes, which ensures that the stereogenic center established by the transaminase is not affected by the monoamine oxidase, and highlights the potential of this multienzyme cascade for the efficient synthesis of chiral building blocks. Mirror mirror on the wall: A ω-transaminase (ω-TA)/monoamine oxidase (MAO-N) cascade process for the asymmetric synthesis of chiral 2,5-disubstituted pyrrolidines is reported. The methodology exploits the complementary regio- and stereoselectivity displayed by both enzymes, which ensures that the stereogenic center established by the TA reaction is not affected by the MAO-N catalyzed step. Copyright
- O'Reilly, Elaine,Iglesias, Cesar,Ghislieri, Diego,Hopwood, Jennifer,Galman, James L.,Lloyd, Richard C.,Turner, Nicholas J.
-
supporting information
p. 2447 - 2450
(2014/03/21)
-
- Anti-tubercular agents. Part 7: A new class of diarylpyrrole-oxazolidinone conjugates as antimycobacterial agents
-
In an effort to discover new anti-tubercular agents, a series of new diarylpyrrole-oxazolidinone conjugates have been designed and synthesized. The anti-tubercular activity of these new conjugates (4a-n and 5a-d) against Mycobacterium tuberculosis H3
- Kamal, Ahmed,Swapna,Shetti, Rajesh V.C.R.N.C.,Shaik, Anver Basha,Narasimha Rao,Sultana, Farheen,Khan, Inshad Ali,Sharma, Sandeep,Kalia, Nitin Pal,Kumar, Sunil,Chandrakant, Bagul
-
p. 239 - 251
(2013/07/27)
-
- Synthesis and study of benzothiazole conjugates in the control of cell proliferation by modulating Ras/MEK/ERK-dependent pathway in MCF-7 cells
-
By applying a methodology, a series of benzothiazole-pyrrole based conjugates (4a-r) were synthesized and evaluated for their antiproliferative activity. Compounds such as 4a, 4c, 4e, 4g-j, 4m, 4n, 4o and 4r exhibited significant cytotoxic effect in the MCF-7 cell line. Cell cycle effects were examined for these conjugates at 2 μM as well as 4 μM concentrations and FACS analysis show an increase of G2/M phase cells with concomitant decrease of G1 phase cells thereby indicating G2/M cell cycle arrest by them. Interestingly 4o and 4r are effective in causing apoptosis in MCF-7 cells. Moreover, 4o showed down regulation of oncogenic expression of Ras and its downstream effector molecules such as MEK1, ERK1/2, p38 MAPK and VEGF. The apoptotic aspect of this conjugate is further evidenced by increased expression of caspase-9 in MCF-7 cells. Hence these small molecules have the potential to control both the cell proliferation as well as the invasion process in the highly malignant breast cancers.
- Kamal, Ahmed,Faazil, Shaikh,Ramaiah, M. Janaki,Ashraf, Md.,Balakrishna,Pushpavalli,Patel, Nibedita,Pal-Bhadra, Manika
-
supporting information
p. 5733 - 5739
(2013/10/01)
-
- Identification of a novel pyrrole derivative endowed with antimycobacterial activity and protection index comparable to that of the current antitubercular drugs streptomycin and rifampin
-
A hit optimization procedure based on isosteric and bioisosteric replacement of decorating groups at both the N1 and the C5 phenyl rings of 1,5-diarylpyrroles led to identification of 4-((1-(4-fluorophenyl)-2-methyl-5- (4-(methylthio)phenyl)-1H-pyrrol-3-yl)methyl)thiomorpholine that is characterized by a very high activity toward both Mycobacterium tuberculosis 103471 and H37Rv strains (MIC values of 0.125 μg/mL), and a safe profile in terms of cytotoxicity (CC50 of >128 μg/mL) and protection index (>1000). Antitubercular activity and protection index of the new compound are comparable to those found for the current antitubercular drugs streptomycin and rifampin.
- Biava, Mariangela,Porretta, Giulio Cesare,Poce, Giovanna,Battilocchio, Claudio,Alfonso, Salvatore,Logu, Alessandro De,Serra, Nadia,Manetti, Fabrizio,Botta, Maurizio
-
experimental part
p. 8076 - 8084
(2011/01/13)
-
- Polarity reversal induced by electrochemically generated thiazol-2-ylidenes: The Stetter reaction
-
The inversion of the normal reactivity (umpolung) of aldehydes has been induced via N-heterocyclic carbenes (NHCs) thiazol-2-ylidenes 2a or 3a, generated by simple electrolyses of solutions containing thiazolium salt 2 or 3. Accordingly, 1,4-dicarbonyl compounds have been obtained, in mild conditions and in moderate to very high yields, via 1,4-addition of the Breslow intermediates to the suitable Michael acceptor. The procedure has been performed in classical organic solvents (VOCs) as well as in room temperature ionic liquids (RTILs). The different reactivity of aliphatic aldehydes vs the one of aromatic and heteroaromatic aldehydes has been emphasized.
- Orsini, Monica,Chiarotto, Isabella,Sotgiu, Giovanni,Inesi, Achille
-
experimental part
p. 3511 - 3517
(2010/07/09)
-
- Carbonylative 1,4-addition of potassium aryltrifluoroborates to vinyl ketones
-
Potassium aryltrifluoroborates have proven to be useful reagents for the carbonylative aroylation of vinyl ketones; this study broadens the scope of potassium aryltrifluoroborates in homogeneous catalysis and shows that the solvent can act as the proton s
- Sauthier, Mathieu,Lamotte, Nicolas,Dheur, Julien,Castanet, Yves,Mortreux, Andre
-
experimental part
p. 969 - 971
(2010/08/21)
-
- Synthesis of furans, pyrroles and pyridazines by a ruthenium-catalysed isomerisation of alkynediols and in situ cyclisation
-
Alkyne-1,4-diols are readily available substrates which are isomerised to 1,4-diketones using Ru(PPh3)3(CO)H2/xantphos as a catalyst. In situ cyclisation into furans, pyrroles and pyridazines has been achieved under suitable conditions.
- Pridmore, Simon J.,Slatford, Paul A.,Taylor, James E.,Whittlesey, Michael K.,Williams, Jonathan M.J.
-
supporting information; experimental part
p. 8981 - 8986
(2009/12/27)
-
- 1,5-Diphenylpyrrole derivatives as antimycobacterial agents. Probing the influence on antimycobacterial activity of lipophilic substituents at the phenyl rings
-
Synthesis and biological evaluation of new derivatives of 1,5-bis(4-chlorophenyl)-2-methyl-3-(4-methylpiperazin-1-yl)methyl-1H-pyrrole (BM 212, 16) are reported. Variously substituted phenyl rings with different substitution pattern and lipophilicity were
- Biava, Mariangela,Porretta, Giulio Cesare,Poce, Giovanna,De Logu, Alessandro,Saddi, Manuela,Meleddu, Rita,Manetti, Fabrizio,De Rossi, Edda,Botta, Maurizio
-
supporting information; experimental part
p. 3644 - 3648
(2009/04/07)
-
- Cyclooxygenase-2 inhibitors. 1,5-diarylpyrrol-3-acetic esters with enhanced inhibitory activity toward cyclooxygenase-2 and improved cyclooxygenase-2/ cyclooxygenase-1 selectivity
-
The important role of cyclooxygenase-2 (COX-2) in the pathogenesis of inflammation and side effect limitations of current COX-2 inhibitor drugs illustrates a need for the design of new compounds based on alternative structural templates. We previously reported a set of substituted 1,5-diarylpyrrole derivatives, along with their inhibitory activity toward COX enzymes. Several compounds proved to be highly selective COX-2 inhibitors and their affinity data were rationalized through docking simulations. In this paper, we describe the synthesis of new 1,5-diarylpyrrole derivatives that were assayed for their in vitro inhibitory effects toward COX isozymes. Among them, the ethyl-2-methyl-5-[4-(methylsulfonyl)phenyl]-1-[3-fluorophenyl]-1H-pyrrol-3- acetate (1d), which was the most potent and COX-2 selective compound, also showed a very interesting in vivo anti-inflammatory and analgesic activity, laying the foundations for developing new lead compounds that could be effective agents in the armamentarium for the management of inflammation and pain.
- Biava, Mariangela,Porretta, Giulio Cesare,Poce, Giovanna,Supino, Sibilla,Forli, Stefano,Rovini, Michele,Cappelli, Andrea,Manetti, Fabrizio,Botta, Maurizio,Sautebin, Lidia,Rossi, Antonietta,Pergola, Carlo,Ghelardini, Carla,Vivoli, Elisa,Makovec, Francesco,Anzellotti, Paola,Patrignani, Paola,Anzini, Maurizio
-
p. 5403 - 5411
(2008/03/14)
-
- 2,5-Disubstituted furans from 1,4-alkynediols
-
1,4-Alkynediols serve as readily available starting materials for isomerisation to 1,4-diketones, which can be converted in situ into the corresponding furans by acid-catalysed dehydration. A range of 2,5-disubstituted furans was prepared using the ruthenium-based catalyst Ru(PPh3)3(CO)H2 with Xantphos at 1 mol % loading.
- Pridmore, Simon J.,Slatford, Paul A.,Williams, Jonathan M.J.
-
p. 5111 - 5114
(2008/02/09)
-
- Antimycobacterial agents. Novel diarylpyrrole derivatives of BM212 endowed with high activity toward Mycobacterium tuberculosis and low cytotoxicity
-
On the basis of suggestions derived either from a pharmacophoric model for antitubercular agents or from a structure-activity relationship analysis of many pyrroles previously described by us, we report here the design and synthesis of new analogues of 1,
- Biava, Mariangela,Porretta, Giulio Cesare,Poce, Giovanna,Supino, Sibilla,Deidda, Delia,Pompei, Raffaello,Molicotti, Paola,Manetti, Fabrizio,Botta, Maurizio
-
p. 4946 - 4952
(2007/10/03)
-
- DERIVATIVES OF 1-{ [1,5-BIS(4-CHLOROPHENYL)-2-METHYL-1H-PYRROL-3-YL] METHYL}-4- METHYLPIPERAZINE, SYNTHESIS PROCESS AND USES THEREOF
-
The present invention concerns pyrrole compounds, derivatives of 1-{[1,5-bis(4- chlorophenyl)-2-methyl-lH-pyrrol-3-yl]methyl}-4-methylpiperazine (BM212). The invention concerns the use of the described compounds as antitubercular agents having high activi
- -
-
Page/Page column 8-10; 12
(2008/06/13)
-
- 1,4-Carbonylative addition of arylboronic acids to methyl vinyl ketone: a new synthetic tool for rapid furan and pyrrole synthesis
-
The rhodium catalysed 1,4-carbonylative addition of arylboronic acids to methyl vinyl ketone under carbon monoxide pressure was studied. High yields of 1,4-diketones were obtained using a catalytic system formed from Rh(COD)2BF4 (COD=1,5-cyclooctadiene) and triphenylphosphine even at very low catalyst loading (0.02 mol %). A short synthetic procedure combining this carbonylation reaction with a subsequent cyclisation step affords pyrroles or furans.
- Chochois, Hélène,Sauthier, Mathieu,Maerten, Eddy,Castanet, Yves,Mortreux, André
-
p. 11740 - 11746
(2007/10/03)
-
- A new method for the synthesis of acyltitanium complexes and their application to copper-mediated acylmetallation of carbon-carbon multiple bonds in aqueous media
-
Treatment of α,β-unsaturated carbonyl compounds or methyl propargyl ether with acylchlorobis(cyclopentadienyl)titanium in the presence of Methylamine and a copper salt in aqueous THF resulted in acylation of the carbon-carbon multiple bond, yielding the c
- Han, Zhenfu,Fujioka, Takuma,Usugi, Shin-Ichi,Yorimitsu, Hideki,Shinokubo, Hiroshi,Oshima, Koichiro
-
p. 1622 - 1623
(2007/10/03)
-
- New synthesis of 1,4-diketones via rhodium-catalysed 1,4 carbonylative addition of arylboronic acids to α,β-unsaturated ketones
-
The reaction of various arylboronic acids with α,β-unsaturated ketones under CO pressure and in the presence of rhodium catalyst yields 1,4-diketones.
- Sauthier, Mathieu,Castanet, Yves,Mortreux, Andre
-
p. 1520 - 1521
(2007/10/03)
-
- Manganese(II and III)-Mediated Synthesis of Cyclic Peroxides from Alkenes, Active Methylene Compounds, and Molecular Oxygen
-
The reaction of 1,1-diphenylethene, 1,1-bis(4-chlorophenyl)ethene, 1,1-bis(4-methylphenyl)ethene, 1,1-bis(4-methoxyphenyl)ethene, and 1,1-bis(4-fluorophenyl)ethene with 2-methyl-1,3-cyclohexanedione, 2-methyl-1,3-cyclopentanedione, 2-acetylcyclohexanone, ethyl 2-acetyl-3-oxobutanoate, 3-methyl-2,4-pentanedione, 1,3-cyclohexanedione, and 2,4-pentanedione in the presence of Mn(OAc)2 and molecular oxygen yielded the corresponding cyclic peroxides in moderate-to-good yields.Similar reaction of 1,1-disubstituted alkenes with 1,3-cyclopentanedione in the presence of Mn(OAc)3 and molecular oxygen gave 2,2,9,9-tetraphenyloctahydro-3,4,7,8-tetraoxabenzindene-4a,6a-diols.Acid-catalyzed decomposition of 4-acetyl-6,6-diaryl-3-methyl-1,2-dioxan-3-ols yielded 3-acetyl-5-aryl-2-methylfurans in moderate yields.Treatment of the 4-acetyl-6,6-diaryl-3-methyl-1,2-dioxan-3-ols with alkali gave 6,6-diaryl-3-methyl-1,2-dioxan-3-ols which gave 1-aryl-1,4-pentanediones upon treatment with hydrochloric acid in acetic acid.The synthetic utility and mechanism of the reactions are discussed.
- Qian, Chang-Yi,Yamada, Takashi,Nishino, Hiroshi,Kurosawa, Kazu
-
p. 1371 - 1378
(2007/10/02)
-
- Formation of 1,2-Dioxanes by the Use of Tris(2,4-pentanedionato)manganese(III) or Manganese(III) Acetate
-
The reactions of 1,1-diphenylethene, 1,1-bis(4-chlorophenyl)ethene, 1,1-bis(4-methoxyphenyl)ethene, 1,1-bis(4-methylphenyl)ethene, 1,1-bis(4-fluorophenyl)ethene, styrene, 1-octene, cyclohexene, and cyclooctene with tris(2,4-pentanedionato)manganese(III) () in acetic acid at room temperature give 4-acetyl-3-methyl-1,2-dioxan-3-ol in 8-92percent yields, together with 3-acetyl-4-hydroxy-3-hexene-2,5-dione.The similar reactions of 1,1-diphenylethene with 2,4-pentanedione, 3-methyl-2,4-pentanedione, 3-ethyl-2,4-pentanedione, 1-phenyl-1,3-butanedione, acetoacetanilide, and 1,3-cyclohexanedione in the presence of manganese(III) acetate also give the corresponding cyclic peroxide in good to moderate yields.The mechanisms of manganese(III)-induced 1,2-dioxane ring formation and concomitant radical side reaction are discussed.
- Nishino, Hiroshi,Tategami, Shin-ichi,Yamada, Takashi,Korp, James D.,Kurosawa, Kazu
-
p. 1800 - 1809
(2007/10/02)
-
- A Simple Synthesis of 2-Cyclopentenone: Synthesis of Dihydrojasmone and α-Cuparenone
-
A simple synthesis of substituted 2-cyclopentenone has been illustrated through the syntheses of dihydrojasmone and α-cuparenone.The route involves elaboration of α,β-unsaturated ketone to 2-cyclopentenone through (i) methylene transfer to double bond, (ii) nucleophilic ring-opening by thiophenoxide anion, (iii) chlorination of thioether and (iv) generation of carbonyl group from α-chlorothioether to afford 1,4-diketone which subsequently cyclises with alkali to the desired 2-cyclopentenone.
- Anand, R. C.,Ranjan, H.
-
p. 673 - 674
(2007/10/02)
-