- Geometrically Selective Denitrative Trifluoromethylthiolation of β-Nitrostyrenes with AgSCF3for (E)-Vinyl Trifluoromethyl Thioethers
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An efficient copper(II)-promoted denitrative trifluoromethylthiolation under mild reaction conditions has been developed for vinyl trifluoromethyl thioethers to construct Cvinyl-SCF3 bonds with stable AgSCF3 as a source of the trifluoromethylthio. This reaction system tolerates a broad range of functional groups to commendably achieve a high product yield and excellent stereoselectivity of E/Z.
- Fang, Ge,Hong, Jianquan,Huang, Shuai,Jiang, Chao,Liu, Yang,Zhang, Wei,Zheng, Changge
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supporting information
(2020/07/03)
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- Chlorination of Conjugated Nitroalkenes with PhICl 2and so 2Cl 2for the Synthesis of α-Chloronitroalkenes
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Chlorination of conjugated nitroalkenes with iodobenzene dichloride or sulfuryl chloride to give target α-chloronitroalkenes in good yields is described. Details of the procedure depend on the donating ability of the nitroalkene substituents. The activity of the described chlorinating agents increases in order 'PhICl 2/Py' 2Cl 2' 2Cl 2/HCl' with the former producing the best yields for highly donating substrates and the latter for non-activated groups. An autocatalytic role of hydrogen chloride and the chemoselectivity of chlorination were also demonstrated.
- Fadeeva, Anastasia A.,Ioffe, Sema L.,Tabolin, Andrey A.
-
supporting information
p. 2679 - 2688
(2020/11/02)
-
- Molecular Engineering of β-Substituted Oxoporphyrinogens for Hydrogen-Bond Donor Catalysis
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A new class of bifunctional hydrogen-bond donor organocatalyst using oxoporphyrinogens having increased intramolecular hydrogen-bond donor distances is reported. Oxoporphyrinogens are highly non-planar rigid macrocycles containing a multiple hydrogen bond-forming binding site. In this work, we describe the first example of non-planar OxPs as hydrogen-bond donor catalysts prepared using a molecular engineering approach of the binding site for dual activation of substrates. The introduction of β-substituents is key to the catalytic activity and the catalysts are able to catalyze 1,4-conjugate additions and sulfa-Michael additions, as well as, Henry and aza-Henry reactions at low catalyst loadings (≤ 1 mol-%) under mild conditions. Preliminary mechanistic studies have been carried out and a possible reaction mechanism has been proposed based on the bi-functional activation of both substrates through hydrogen-bonding interactions.
- Chahal, Mandeep K.,Payne, Daniel T.,Matsushita, Yoshitaka,Labuta, Jan,Ariga, Katsuhiko,Hill, Jonathan P.
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supporting information
p. 82 - 90
(2020/01/02)
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- A photocatalyst-free photo-induced denitroalkylation of β-nitrostyrenes with 4-alkyl substituted Hantzsch esters at room temperature
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A photocatalyst-free stereoselectively photo-induced strategy for the denitroalkylation of β-nitrostyrenes using 4-alkyl substituted Hantzsch esters as the alkyl source under xenon lamp irradiation is developed. The reaction proceeds at room temperature and affords the corresponding products in moderate to excellent yields. The oxidant di-t-butyl peroxide serves as an efficient radical initiator under irradiation of a Xenon lamp, initiating alkyl radicals from the 4-alkyl substituted Hantzsch esters.
- Duan, Chunying,Hao, Xinyu,Jin, Kun,Li, Yaming,Wang, Jiaao,Zhang, Rong,Zhang, Siyu
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supporting information
(2020/02/18)
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- Synthetic Diversity from a Versatile and Radical Nitrating Reagent
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We leverage the slow liberation of nitrogen dioxide from a newly discovered, inexpensive succinimide-derived reagent to allow for the C?H diversification of alkenes and alkynes. Beyond furnishing a library of aryl β-nitroalkenes, this reagent provides unparalleled access to β-nitrohydrins and β-nitroethers. Detailed mechanistic studies strongly suggest that a mesolytic N?N bond fragmentation liberates a nitryl radical. Using in situ photo-sensitized, electron paramagnetic resonance spectroscopy, we observed direct evidence of a nitryl radical in solution by nitrone spin-trapping. To further exhibit versatility of N-nitrosuccinimide under photoredox conditions, the late-stage diversification of an extensive number of C?H partners to prepare isoxazolines and isoxazoles is presented. This approach allows for the formation of an in situ nitrile oxide from a ketone partner, the presence of which is detected by the formation of the corresponding furoxan when conducted in the absence of a dipolarophile. This 1,3-dipolar cycloaddition with nitrile oxides and alkenes or alkynes proceeds in a single-operational step using a mild, regioselective, and general protocol with broad chemoselectivity.
- Zhang, Kun,Jelier, Benson,Passera, Alessandro,Jeschke, Gunnar,Katayev, Dmitry
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supporting information
p. 12929 - 12939
(2019/09/17)
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- Metal-free, room temperature, acid-K2S2O8 mediated method for the nitration of olefins: An easy approach for the synthesis of nitroolefins
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Here, we have developed a simple, room temperature method for the nitration of olefins by using inexpensive sodium nitrite as a source of nitro groups in the presence of trifluoroacetic acid (TFA) and potassium persulfate (K2S2O8) under an open atmosphere. Styrenes and mono-substituted olefins give stereo-selective corresponding E-nitroolefins under optimized conditions, however, 1,1-bisubstituted olefins give a mixture of E- and Z-nitroolefins. The optimized conditions work well with electron-donating, electron-withdrawing, un-substituted and heterocyclic styrenes and mono-substituted olefins and give corresponding nitroolefins with good to excellent yields.
- Ambala, Srinivas,Singh, Rohit,Singh, Maninder,Cham, Pankaj Singh,Gupta, Ria,Munagala, Gurunadham,Yempalla, Kushalava Reddy,Vishwakarma, Ram A.,Singh, Parvinder Pal
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p. 30428 - 30431
(2019/10/04)
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- Synthesis of Functionalized Indolines and Dihydrobenzofurans by Iron and Copper Catalyzed Aryl C-N and C-O Bond Formation
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A simple and effective one-pot, two-step intramolecular aryl C-N and C-O bond forming process for the preparation of a wide range of benzo-fused heterocyclic scaffolds using iron and copper catalysis is described. Activated aryl rings were subjected to a highly regioselective, iron(III) triflimide-catalyzed iodination, followed by a copper(I)-catalyzed intramolecular N-or O-arylation step leading to indolines, dihydrobenzofurans, and six-membered analogues. The general applicability and functional group tolerance of this method were exemplified by the total synthesis of the neolignan natural product, (+)-obtusafuran. DFT calculations using Fukui functions were also performed, providing a molecular orbital rationale for the highly regioselective arene iodination process.
- Henry, Martyn C.,Senn, Hans Martin,Sutherland, Andrew
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p. 346 - 364
(2019/01/08)
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- Iodine monobromide catalysed regioselective synthesis of 3-arylquinolines from α-aminoacetophenones and: Trans -β-nitrostyrenes
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A simple and efficient method for regioselective synthesis of 3-arylquinolines is described from α-aminoacetophenones and trans-β-nitrostyrenes using 20 mol% iodine monobromide as a catalyst in acetonitrile solvent at 80 °C. The present method involves tandem reaction of α-aminoacetophenones and trans-β-nitrostyrenes, formation of two new C-C bonds and cleavage of one C-C bond in a single step. The salient features of the protocol are metal- and oxidant-free reaction conditions, broad substrate scope, and good yields.
- Gattu, Radhakrishna,Mondal, Santa,Ali, Saghir,Khan, Abu T.
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supporting information
p. 347 - 353
(2019/01/10)
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- Synthesis of nitroolefins and nitroarenes under mild conditions
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1,3-Disulfonic acid imidazolium nitrate {[Dsim]NO3} was prepared and characterized as a new ionic liquid and nitrating agent for the ipso-nitration of various arylboronic acids and nitro-Hunsdiecker reaction of different α,β-unsaturated acids and benzoic acid derivatives, by in situ generation of NO2 to give various nitroarenes and nitroolefins without using any cocatalysts and solvents under mild conditions.
- Zarei, Mahmoud,Noroozizadeh, Ehsan,Moosavi-Zare, Ahmad R.,Zolfigol, Mohammad A.
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p. 3645 - 3650
(2018/04/14)
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- Access to C5-Alkylated Indolines/Indoles via Michael-Type Friedel-Crafts Alkylation Using Aryl-Nitroolefins
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A straightforward synthetic route toward C5-alkylated indolines/indoles has been developed. The strategy is composed of Zn(OTf)2-catalyzed Friedel-Crafts alkylation of N-benzylindolines with nitroolefins, and a series of diverse indolines was first obtained in up to 99% yield. This reaction provides a direct and practical route to a variety of the C5-alkylated indolines which were also utilized for accessing corresponding indoles. Indoline derivatives with free NH groups could be obtained through an N-deprotection reaction. Moreover, the primary alkyl nitro groups in both indolines and indoles are amenable to further synthetic elaborations, thereby broadening the diversity of the products.
- Ertugrul, Berrak,Kilic, Haydar,Lafzi, Farrokh,Saracoglu, Nurullah
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p. 9018 - 9038
(2018/06/27)
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- Synthesis, antiproliferative and pro-apoptotic effects of nitrostyrenes and related compounds in Burkitt’s lymphoma
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Background: Cancers of the lymphatic cells (lymphomas) account for approximately 12% of malignant diseases worldwide. The nitrostyrene scaffold is identified as a lead target structure for the development of particularly effective compounds targeting Burkitt’s lymphoma (BL). Objectives: The aims of the curent study were to synthesise a panel of nitrostyrene compounds and to evaluate their activity in Burkitt’s lymphoma (BL). Methods: A panel of structurally varied compounds were designed and synthesised using Henry Knoevenagel condensation reactions. Single crystal X-Ray analysis confirmed the E configuration for six examples of these novel structures. A number of nitrostyrene-related compounds were also investigated including 1,3-bis(aryl)-2-nitropropenes together with heterocyclic scaffolds containing the nitrovinyl pharmacophore such as 3-nitro-2-phenyl-2H-chromenes. The antiproliferative activities of the compounds were evaluated using the BL cell lines EBV- MUTU-1 and EBV+ DG-75 (chemoresistant) to establish preliminary structure-activity relationships. Results: Lead compounds with optimized nitrostyrene scaffolds and 3-nitro-2-phenyl-2Hchromene structures were successfully established with typical IC50 values of 0.45 μM and 0.47 μM in MUTU-1 cells and 1.41 μM and 1.92 μM, respectively, in DG-75 cells. The mechanism of cell death was identified as apoptotic and the lead compound was found to elicit comparable apoptotic effects to Taxol in Burkitt’s lymphoma cell lines MUTU-1 and DG-75. Conclusion: This class of pharmaceutically active compounds with potential for the treatment of Burkitt’s lymphoma suggest a potential role for nitrostyrene based agents in chemotherapy.
- Byrne, Andrew J.,Bright, Sandra A.,Fayne, Darren,McKeown, James P.,McCabe, Thomas,Twamley, Brendan,Williams, Clive,Meegan, Mary J.
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p. 181 - 199
(2018/03/13)
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- Electronic effect of substituents on anilines favors 1,4-addition to: Trans -β-nitrostyrenes: Access to N -substituted 3-arylindoles and 3-arylindoles
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A simple and an efficient method for the regioselective synthesis of N-alkyl/aryl/H 3-arylindole derivatives from N-substituted anilines and trans-β-nitrostyrenes has been described using 10 mol% of bismuth(iii) triflate as a catalyst in acetonitrile at 80 °C. The present protocol profits from the formation of new C-C and C-N bonds, broad substrate scope and moderate to good yields.
- Gattu, Radhakrishna,Bhattacharjee, Suchandra,Mahato, Karuna,Khan, Abu T.
-
supporting information
p. 3760 - 3770
(2018/05/30)
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- Fe(III)/Pyridine-Mediated Decarboxylative Nitration of α,β-Unsaturated Acids with Iron Nitrate
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A novel and efficient method for the synthesis of (E)-nitroolefins in moderate to excellent yields is developed by Fe(III)/pyridine-mediated decarboxylative nitration of α,β-unsaturated acids with iron nitrate. A series of α,β-unsaturated acids are well tolerated in this procedure.
- Yang, Zan,Li, Jiao,Hua, Jie,Yang, Tao,Yi, Jianmin,Zhou, Congshan
-
supporting information
p. 1079 - 1082
(2017/05/19)
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- Multicomponent synthesis of 4-aryl-NH-1,2,3-triazoles in the presence of Al-MCM-41 and sulfated zirconia
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The acid properties of Al-MCM-41 and sulfated zirconia were used to develop a strategy for the synthesis of 4-aryl-NH-1,2,3-triazoles via a multicomponent reaction involving various benzaldehydes, sodium azide and nitromethane. The efficiency of the process is analysed from the perspective of the difference in acids among the catalysts used.
- Vergara-Arenas, Blanca Ivonne,Lomas-Romero, Leticia,ángeles-Beltrán, Deyanira,Negrón-Silva, Guillermo Enrique,Gutiérrez-Carrillo, Atilano,Lara, Víctor Hugo,Morales-Serna, José Antonio
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supporting information
p. 2690 - 2694
(2017/06/23)
-
- Tetraarylphosphonium inner-salts (TAPIS) as both Lewis base catalyst and phase tag
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Tetraarylphosphonium inner-salts (TAPIS) have been designed, synthesized and verified as recyclable and reusable Lewis base catalysts. The resulted TAPIS catalyst has been successfully applied in Michael addition, cyanation and trifluoromethylation reactions.
- Guo, Shuhui,Mi, Xueling
-
supporting information
p. 2881 - 2884
(2017/07/11)
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- Cu(NO3)2-catalyzed nitrodecarboxylation of α,β-unsaturated acids: facile synthesis of (E)-nitroolefins under additive-free conditions
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Abstract: An additive-free, facile, efficient, and ecofriendly protocol for synthesis of (E)-nitroolefins via nitrodecarboxylation of α,β-unsaturated acids has been developed. Cu(NO3)2 was used as both nitrating agent and catalyst. Furthermore, the presented methodology offers several advantages such as easily accessible and stable substrates, inexpensive catalyst, high to excellent yield, short reaction time, and simple posttreatment procedure. Graphical Abstract: [Figure not available: see fulltext.]
- Luo, Zai-Gang,Xu, Feng,Fang, Yu-Yu,Liu, Peng,Xu, Xue-Mei,Feng, Cheng-Tao,Li, Zhong,He, Jie
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p. 6079 - 6087
(2016/06/01)
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- Iron-Mediated One-Pot Synthesis of 3,5-Diarylpyridines from β-Nitrostyrenes
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An operationally simple and mild one-pot protocol for the synthesis of a variety of 3,5-diarylpyridines from β-nitrostyrenes was achieved by using elemental iron. This reaction proceeds via reduction of the nitro group, resulting in in situ imine formation followed by trimolecular condensation with concomitant debenzylative aromatization. By employing this method, a series of symmetrical and unsymmetrical 3,5-diarylpyridines were synthesized with good to excellent yields. In addition, this method was also utilized for the synthesis of Sch-21418, an anti-inflammatory agent on gram scale.
- Sathish, Manda,Chetna, Jadala,Hari Krishna, Namballa,Shankaraiah, Nagula,Alarifi, Abdullah,Kamal, Ahmed
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p. 2159 - 2165
(2016/03/15)
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- Mild and efficient reductive deoxygenation of epoxides to olefins with tin(II) chloride/sodium iodide as a novel reagent
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A highly efficient and green protocol is reported for the reductive deoxygenation of organic epoxides to olefins using tin(II) chloride/sodium iodide as a novel reagent. The reaction gives an excellent yield (85-96%) in ethanol under reflux within 2-10 minutes, without affecting other functional groups. The advantages of our method are the use of inexpensive reagents, the eco-friendly and green reaction conditions, and the short reaction times and high yields.
- Pathe, Gulab Khushalrao,Ahmed, Naseem
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supporting information
p. 3542 - 3552
(2015/11/17)
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- Synthesis of β-nitrostyrenes in the presence of sulfated zirconia and secondary amines
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A simple and efficient protocol for the synthesis of β-nitrostyrenes has been achieved by the use of sulfated zirconia-secondary amine (piperidine, pyrrolidine, proline or prolinol) cooperative systems. The condensation of different aldehydes and nitromethane demonstrates the efficiency of this process, which does not require high-temperature reactivation for the reuse of the catalytic material.
- González-Olvera,Vergara-Arenas,Negrón-Silva,Angeles-Beltrán,Lomas-Romero,Gutiérrez-Carrillo,Lara,Morales-Serna
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p. 99188 - 99192
(2015/12/05)
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- Clay-supported copper nitrate (claycop): A mild reagent for the selective nitration of aromatic olefins
-
A straightforward and highly selective method has been developed for the nitration of a wide variety of aromatic and aliphatic olefins by using a clay-supported copper nitrate (Claycop) and a catalytic amount of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl, an inexpensive and mild reagent system. High conversions and exclusive E-selectivity, together with the environmentally benign nature of the Claycop reagent, make this a green method and an attractive alternative to established methods. Georg Thieme Verlag Stuttgart. New York.
- Begari, Eeshwaraiah,Singh, Chandani,Nookaraju,Kumar, Pradeep
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p. 1997 - 2000
(2014/11/08)
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- Useful extensions of the henry reaction: Expeditious routes to nitroalkanes and nitroalkenes in aqueous media
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The products of the Henry nitroaldol reaction from nitromethane and several aldehydes were reduced to the corresponding nitroalkanes with (n-Bu) 3SnH in water under microwave irradiation (80 °C/10 min), or dehydrated to the corresponding nitroalkenes with K2CO3 in water (generally 0-5 °C/20 min). Both "one-pot" reactions occur in excellent yields across a range of aliphatic and aromatic (including heteroaromatic) substrates. It seems likely that the deoxygenation of the nitroaldols occurs via coordination of an oxygen atom of the nitro group with a tin atom, which facilitates hydride delivery in the transition state. The elimination of water from the nitroaldols in mild base is likely driven by the stability of the conjugated nitroalkene products. The elimination required workup with 2 N HCl, which likely displaces a nitroalkane-nitroalkene equilibrium towards the latter. These extensions of the Henry reaction lead to products not easily obtained otherwise.
- Chandrasekhar, Sosale,Shrinidhi, Annadka
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p. 3008 - 3018
(2014/10/16)
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- Synthesis of (E)-nitroolefins via decarboxylative nitration using t-butylnitrite (t-BuONO) and TEMPO
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Nitroolefins are usually synthesized using the Henry reaction. Here we report an alternative metal-free decarboxylative nitration protocol for the preparation of the nitroolefins from α,β-unsaturated carboxylic acids using t-butylnitrite (t-BuONO) and TEMPO. α,β-Unsaturated carboxylic acids bearing β-aromatic and β-heteroaromatic substituents gave (E)-nitroolefins exclusively under mild conditions. A radical based pathway has been proposed for this decarboxylative nitration reaction. The Royal Society of Chemistry 2013.
- Manna, Srimanta,Jana, Sandipan,Saboo, Tapish,Maji, Arun,Maiti, Debabrata
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supporting information
p. 5286 - 5288
(2013/06/27)
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- Synthesis of nitroalkenes involving a cooperative catalytic action of iron(III) and piperidine: A one-pot synthetic strategy to 3-alkylindoles, 2H-chromenes and N-arylpyrrole
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An efficient and simple strategy has been developed to synthesize various substituted nitroalkenes involving a cooperative catalytic system of FeCl 3 and piperidine. This dual catalytic protocol simultaneously activates both electrophile and nucleophile and works under mild reaction conditions so that many sensitive functional groups were tolerated. Moreover, this cooperative catalytic reaction is also suitable for various one-pot reactions involving nitroalkenes such as, 2H-chromenes, N-arylpyrrole and Michael reaction with indole. Notably, this method is low-cost, efficient and environmentally friendly. Copyright
- Jalal, Swapnadeep,Sarkar, Soumen,Bera, Krishnendu,Maiti, Sukhendu,Jana, Umasish
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supporting information
p. 4823 - 4828
(2013/08/23)
-
- Regio- and stereoselective synthesis of spirooxindole 1′-nitro pyrrolizidines with five concurrent stereocenters under aqueous medium and their bioprospection using the zebrafish (Danio rerio) embryo model
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A highly regio- and stereoselective method has been developed and expanded for the synthesis of a 20-membered library of spirooxindole 1′-nitro pyrrolizidines via 1,3-dipolar cycloaddition of azomethine ylides, generated in situ by a decarboxylative route from a common set of diverse isatins and l-proline derivatives, with substituted β-nitrostyrenes under aqueous medium. Among various reaction conditions, water proved to be necessary for the interaction of the reagents as well as heating the reaction at 90 °C for one hour, during which time the desired products were obtained in good yields and with excellent regio- and stereoselectivities. We subsequently applied in silico drug discovery computational methods to (i) identify the ADME properties, based on Lipinski's rule, (ii) screen the toxicological profile, and (iii) predict the penetration through the blood brain barrier (BBB) of the synthesized compounds. Next, the LC50 values of all these spirocyclic oxindoles were determined in zebrafish embryos cultured individually in buffer solutions of each compound and, finally, the phenotypes induced by these molecules in the zebrafish embryos at concentrations below their LC50 were analyzed at 48, 72 and 96 hours post fertilization.
- Puerto Galvis, Carlos E.,Kouznetsov, Vladimir V.
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p. 7372 - 7386
(2013/10/22)
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- E-Combretastatin and E-resveratrol structural modifications: Antimicrobial and cancer cell growth inhibitory β-E-nitrostyrenes
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As part of a broad-based SAR investigation of E-resveratrol (strong sirtuin activator and antineoplastic) and the anticancer vascular-targeting combretastatin-type stilbenes, a series of twenty-three β-E-nitrostyrenes was synthesized in order to evaluate potential antineoplastic, antitubulin, and antimicrobial activities. The β-E-nitrostyrenes evaluated ranged from monosubstituted phenols to trimethoxy and 3-methoxy-4,5-methylenedioxy derivatives. Two of the β-nitrostyrenes were synthesized as water-soluble sodium phosphate derivatives (4t, 4v). All except four (4r, 4s, 4t, 4u) of the series significantly inhibited a minipanel of human cancer cell lines. All but eight led to an IC50 of 10 μM for inhibition of tubulin polymerization, and all except three (4l, 4t, 4v) displayed antimicrobial activity.
- Pettit, Robin K.,Pettit, George R.,Hamel, Ernest,Hogan, Fiona,Moser, Bryan R.,Wolf, Sonja,Pon, Sandy,Chapuis, Jean-Charles,Schmidt, Jean M.
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experimental part
p. 6606 - 6612
(2009/12/06)
-
- Investigation of pore-size effects on base catalysis using amino-functionalized monodispersed mesoporous silica spheres as a model catalyst
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The effects of pore size on base catalysis have been studied using amino-functionalized monodispersed mesoporous silica spheres (NH2-MMSS). By changing the surfactant that is used for the template and also the synthetic conditions, NH2/su
- Suzuki, Tomiko M.,Yamamoto, Masami,Fukumoto, Keiko,Akimoto, Yusuke,Yano, Kazuhisa
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p. 249 - 257
(2008/09/17)
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- An efficient synthesis of conjugated nitro-olefins using ceric ammonium nitrate
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An efficient method for the synthesis of conjugated nitro-olefins from α,β-unsaturated acids under extremely mild conditions using ceric ammonium nitrate (CAN) at room temperature in acetonitrile in moderate to good yields is described.
- Sridhar Rao,Srinivas,Suresh Babu,Madhusudana Rao
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p. 8141 - 8143
(2007/10/03)
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- A New and Efficient Synthesis of Pyrrolo[2,3-d]pyrimidine Anticancer Agents: Alimta (LY231514, MTA), Homo-Alimta, TNP-351, and Some Aryl 5-Substituted Pyrrolo[2,3-d]pyrimidines
-
Alimta, as well as homo-Alimta, a nonbridged analogue of Alimta, and TNP-351 have been prepared by a new method that involves Michael addition of the appropriate 1-nitroalkene with 2,6-diamino-3H-pyrimidin-4-one or 2,4,6-triaminopyrimidine, followed by a Nef reaction of the resulting primary nitro Michael adduct. Spontaneous intramolecular cyclization of the resulting aldehyde with the pyrimidine 6-amino group yields the corresponding pyrrolo[2,3-d]pyrimidine. A series of previously unknown 5-arylpyrrolo[2,3-d]pyrimidines was prepared by the same methodology from the above pyrimidines and nitrostyrenes. It has been found that the intermediate primary nitro Michael adduct can be prepared in a single step by sonication of a mixture of an arylaldehyde, nitromethane, and the 6-aminopyrimidine in acetic acid containing ammonium acetate.
- Taylor, Edward C.,Liu, Bin
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p. 9938 - 9947
(2007/10/03)
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- Structure activity analysis of the pro-apoptotic, antitumor effect of nitrostyrene adducts and related compounds
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In the present study, we outlined the part of the molecule mediating the prominent pro-apoptotic effect of the Michael adduct of ascorbic acid with p-chloro-nitrostyrene, a new synthetic phosphatase inhibitor. The nitrostyrene (NS) moiety was identified as the structure essential for apoptosis induction. NS and its ascorbic acid adducts displayed LC50 values of 10-25μM with no significant reduction of potency in okadaic acid resistant cells overexpressing the MDR1 P-glycoprotein. Induction of apoptosis by NS derivatives and the protein phosphatase 2A inhibitor cantharidic acid was proven by the analysis of caspase-3 activation and subsequent fragmentation of DNA. Further structure activity analysis revealed the necessity of the nitro group at the β-position of the side chain. The pro-apoptotic potential of adducts of NS with pyrimidine- or pyridine-derivatives varied between NS and a progressive reduction in potency up to a nearly complete loss of cytotoxicity. Substitutions at the benzene core of NS suggested a prominent enhancement of toxicity only by substitutions at the 2- or 3-position. Heterocyclic aromatics can substitute for the benzene ring of NS albeit with a 2-3-fold reduced potency. In conclusion, nitrostyrene was identified as the core structure mediating the pro-apoptotic effect of a new synthetic phosphatase inhibitor. Further studies defined a nitrovinyl side chain attached to an aromatic ring as the pharmacophore structure of a new group of pro-apoptotic agents. These observations present the basis for the development of a new group of anticancer drugs.
- Kaap, Sylvia,Quentin, Iris,Tamiru, Dereje,Shaheen, Mohammed,Eger, Kurt,Steinfelder, Hans Juergen
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p. 603 - 610
(2007/10/03)
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- A Nitro-Hunsdiecker Reaction: From Unsaturated Carboxylic Acids to Nitrostyrenes and Nitroarenes
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(Formula Presented) The nitrodecarboxylation of aromatic α,β-unsaturated carboxylic acids and ring-activated benzoic acids can be achieved using nitric acid (3 equiv) and catalytic AIBN (2 mol %) in MeCN. From the effect of various additives, the nitrodecarboxylation is postulated to involve the generation of an acyloxy radical RCO2? by a NO3? radical followed by attack of a NO2? radical.
- Das, Jaya Prakash,Sinha, Pradipta,Roy, Sujit
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p. 3055 - 3058
(2007/10/03)
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- Heterogeneous catalysts in the preparation of 2-aryl-1,3-dinitropropanes from β-nitrostyrenes or benzaldehydes
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The use of heterogeneous basic catalysts (KF, NaHCO3) in the preparation of 2-Aryl-1,3-dinitropropanes from β-nitrostyrenes or benzaldehydes is described, with one example followed kinetically by HPLC analysis of aliquots of the reaction.
- Fierro,Rezende,Sepulveda-Boza,Reyes-Parada,Cassels
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p. 294 - 296
(2007/10/03)
-
- One-pot synthesis of trans-β-alkylstyrenes
-
One-pot synthesis of (E)-alkenes 5 from the reactions of aldehyde 1 and nitromethane 2 in the acetic acid solution and then with triethylborane 4 in the biphase of diethyl ether and aqueous solution in the presence of oxygen in air was reported. Various (E)-alkenes 7 could also be prepared when different kinds of secondary or tertiary alkyl iodides 6 were used under similar conditions.
- Liu, Ju-Tsung,Yao, Ching-Fa
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p. 6147 - 6150
(2007/10/03)
-