- Direct para-Selective C-H Amination of Iodobenzenes: Highly Efficient Approach for the Synthesis of Diarylamines
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Iodine(III)-mediated synthesis of 4-iodo-N-phenylaniline from iodobenzene has been achieved, and the reaction can proceed under mild conditions. A variety of functional groups were well tolerated, providing the corresponding products in moderate to good yields. The remaining iodine group provides an effective platform for converting the products into several valuable asymmetric diphenylamines. Most importantly, this reaction can be easily scaled up to the ten-gram scale, highlighting its synthetic utility. The mechanistic study revealed that the in situ generated aryl hypervalent iodine intermediate is the key factor to realize this para-selective C-H amination reaction.
- Chen, Yujie,Huang, Zhibin,Jiang, Yaqiqi,Shu, Sai,Yang, Shan,Shi, Da-Qing,Zhao, Yingsheng
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p. 8226 - 8235
(2021/06/28)
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- Catalyst-free generation of acyl radicals induced by visible light in water to construct C-N bonds
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We describe herein a catalyst-free and redox-neutral photochemical strategy for the direct generation of acyl radicals from α-diketones, and its selective conversion of nitrosoarenes to hydroxyamides or amides with AcOH or NaCl as an additive. The reaction was carried out under mild conditions in water with purple LEDs as the light source. A broad scope of substrates was demonstrated. Mechanistic experiments indicate that α-diketones cleave to give acyl radicals, with hydroxyamides being further reduced to amides.
- Ran, Maogang,He, Jiaxin,Yan, Boyu,Liu, Wenbo,Li, Yi,Fu, Yunfen,Li, Chao-Jun,Yao, Qiuli
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supporting information
p. 1970 - 1975
(2021/03/16)
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- Utilization of ultrasonic as an approach of green chemistry for synthesis of hydrazones and bishydrazones as potential antimicrobial agents
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Hydrazides 3,4, Hydrazones 6a-c, bishydrazones 8a,b, N-hydroxy-N'- arylpropanehydrazonamide 9a,b and 1-(piperidin-1-yl)-N2-arylamidrazones 10a,b were prepared under ultrasonic waves as an approach for green chemistry. a notable good yield and short reaction time were afforded under ultrasonic waves.The structures of compounds were confirmed in terms of spectroscopic and elemental analyses. The invitro antimicrobial activity of the prepared compounds were evaluated. most of compounds exhibited an excellent growth inhibition such as compounds 2, 3 and 8b against gram positive bacteria, while 2, 3, 8b, 9a, 10a and 10b against gram negative bacteria. all of tested compounds have excellent or good antifungal activity except 3.
- Younis, Ahmed,Awad, Ghada E. A.
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p. 599 - 610
(2020/05/28)
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- 3,6-Di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) catalysed metal-free amide bond formation from thioacids and amines at room temperature
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A 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) catalysed efficient, mild and metal-free method has been developed for direct amide bond synthesis from simple thioacids and amines as starting materials. This methodology is useful for aromatic, aliphatic, and heteroaromatic thioacids as well as primary, secondary, heterocyclic, and even functionalized amines. A wide substrates scope, operationally mild conditions, and acylation of amines without affecting other functional groups such as alcohols, esters, carbodithioates, among others make this strategy very attractive and practical.
- Samanta, Suvendu,Ray, Shounak,Bhaduri, Samanka Narayan,Samanta, Partha Kumar,Biswas, Papu
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supporting information
(2020/08/10)
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- Synthesis, chemical characterization and antimicrobial activity of new acylhydrazones derived from carbohydrates
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A new series of glycosylated acylhydrazones was synthesized and all the chemical structures were confirmed by High Resolution Mass Spectrometry (HRMS), 1H and 13C Nuclear Magnetic Resonance (1H-NMR; 13C-NMR) and Fourier Transform Infrared (FTIR) spectroscopy methods. The mass accuracy between the calculated and found values observed in HRMS analyses were near or lower than 5 ppm, which are acceptable for proposing a molecular formula using this technique. All of the synthesized compounds were screened for their antibacterial, antifungal and antiviral activities. Five compounds (12, 13, 14, 16 and 19) exerted a modest antifungal activity against the strains evaluated. Derivative 14 showed fungicidal activity against Candida glabrata at 173.8 μM and saccharide unit contributed to the increase of the antifungal potential against this strain. New chemical manipulation of derivative 14 can make it possible to obtain new potentially antimicrobial agents.
- Guilherme, Fernanda Dias,Simonetti, Julia évelin,Folquitto, Lais Regina Santos,Reis, Adriana Cotta Cardoso,Oliver, Josidel Concei??o,Dias, Amanda Latércia Tranches,Dias, Danielle Ferreira,Carvalho, Diogo Teixeira,Brand?o, Geraldo Célio,Souza, Thiago Belarmino de
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p. 349 - 356
(2019/03/04)
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- General rhodium-catalyzed oxidative cross-coupling reactions between anilines: Synthesis of unsymmetrical 2,2′-diaminobiaryls
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Described herein is a dual chelation-assisted RhCl3-catalyzed oxidative C-H/C-H cross-coupling reaction of aniline derivatives. The highlight of this methodology is the chemo- and regioselective cross-coupling between electronically similar substrates, which represents a highly challenging task in oxidative Ar-H/Ar-H cross-coupling reactions. Furthermore, this Cp?-free catalytic reaction tolerates a range of functional groups and requires only a low molar ratio of coupling partners. These features expedite the synthesis of unsymmetrical 2,2′-diaminobiaryls.
- Shi, Yang,Liu, Jiahui,Yang, Yudong,You, Jingsong
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supporting information
p. 5475 - 5478
(2019/05/16)
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- Synthesis of acetamides from aryl amines and acetonitrile by diazotization under metal-free conditions
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An efficient and metal-free coupling reaction has been developed that affords acetamides from the corresponding aryl amines and acetonitrile. This method tolerates a wide range of functional groups and is selective toward aryl amines. Preliminary mechanistic studies were conducted.
- Duan, Pan,Guo, Yu,Kang, Huan,Li, Yi-Na,Wen, Xianghao,Xiao, Fang,Zeng, Yao-Fu,Zhang, Na-Na
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supporting information
p. 2169 - 2172
(2019/11/25)
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- Synthesis of Arylamides via Ritter-Type Cleavage of Solid-Supported Aryltriazenes
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A novel route for the synthesis of N-arylamides via the cleavage of aryltriazenes with alkyl or aryl nitriles is presented. We developed a variation of the Ritter reaction that allows the use of acetonitrile as solvent and reagent in reactions with solid-supported precursors. The reaction was optimized for the generation of N-aryl acetamides using a diverse range of immobilized building blocks including o-, m-, and p-substituted aryltriazenes. The cleavage via the Ritter-type conversion was combined with an on-bead cross-coupling reaction of halogen-substituted aryltriazenes with pyrazoles. Additionally, the synthesis of on-bead generated arylboronic ester-substituted triazenes was shown. The developed procedure was further expanded to use other commercially available nitriles, such as acrylonitrile, benzonitrile, and chlorinated alkyl nitriles as suitable reagents for a Ritter-type cleavage of the prepared triazene linkers.
- Wippert, Nicolai A.,Jung, Nicole,Br?se, Stefan
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supporting information
p. 568 - 572
(2019/09/03)
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- Microwave-mediated Green chemistry approach for the synthesis of some chalcone derivatives and evaluation of their anthelmintic activity
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In the present study, microwave-mediated Green chemistry approach is followed to prepare some chalcone derivatives. For this purpose, microwave heating technology is used as the alternative energy sources to synthesize a series of chalcone derivatives by Claisen-Schmidt condensation of ethyl 4-acetamidobenzoate with various aromatic aldehydes in the presence of ethanolic sodium hydroxide solution followed by dehydration. With the help of microwave, the rate of reaction is increased with less byproduct formation and better yield of the product. The structures of the newly synthesized compounds are confirmed by FT-IR, 1H NMR, mass spectra and CHN analyses. The titled compounds are screened for their anthelmintic activity and significant activity as compared to the standard drug is found. Compounds with electron withdrawing groups are found to be highly potent among the series.
- Sahoo, Biswa Mohan,Srinivasa Rao,Banik, Bimal Krishna,Sahoo, Kishore Chandra
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p. 1295 - 1299
(2020/06/27)
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- Visible light driven amide synthesis in water at room temperature from Thioacid and amine using CdS nanoparticles as heterogeneous Photocatalyst
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Highly efficient photocatalytic thioacid mediated amide synthesis at room temperature using CdS nanoparticles as photocatalyst was observed under a household 30?W CFL in water. The operationally mild reaction was tolerant to a number of functional group substitutions on amine and could be scaled up to gram. This heterogeneous photocatalyst was extremely stable and could easily be recovered by simple centrifugation for at least six recycling reactions without any significant loss of catalytic performance. The possible reaction mechanism for the photocatalytic thioacid mediated amide synthesis over the CdS semiconductor has also been proposed on the basis of experimental observations.
- Das, Sudipto,Ray, Shounak,Ghosh, Abhisek Brata,Samanta, Partha Kumar,Samanta, Suvendu,Adhikary, Bibhutosh,Biswas, Papu
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- Visible-Light-Promoted C-H Arylation by Merging Palladium Catalysis with Organic Photoredox Catalysis
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The use of a dual palladium/organic photoredox catalytic system enables the directed arylation of arenes with aryldiazonium salts with a broad substrate scope at room temperature under mild reaction conditions. This study thus serves as not only an alternative route for the biaryl motifs but also a new example for the application of an organic photoredox catalyst.
- Jiang, Jian,Zhang, Wen-Man,Dai, Jian-Jun,Xu, Jun,Xu, Hua-Jian
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p. 3622 - 3630
(2017/04/11)
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- Benzoic acid derivatives with trypanocidal activity: Enzymatic analysis and molecular docking studies toward trans-sialidase
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Chagas, or American trypanosomiasis, remains an important public health problem in developing countries. In the last decade, trans-sialidase has become a pharmacological target for new anti-Chagas drugs. In this work, the aims were to design and find a new series of benzoic acid derivatives as trans-sialidase (TS) inhibitors and anti-trypanosomal agents. Three compounds (14, 18, and 19) sharing a para-aminobenzoic acid moiety showed more potent trypanocidal activity than the commercially available drugs nifurtimox and benznidazole in both strains: the lysis concentration of 50% of the population (LC50) was 0.15 μM on the NINOA strain, and LC50 0.22 μM on the INC-5 strain. Additionally, compound 18 showed a moderate inhibition (47%) on the trans-sialidase enzyme and a binding model similar to DANA (pattern A).
- Kashif, Muhammad,Moreno-Herrera, Antonio,Villalobos-Rocha, Juan Carlos,Nogueda-Torres, Benjamín,Pérez-Villanueva, Jaime,Rodríguez-Villar, Karen,Medina-Franco, José Luis,De Andrade, Peterson,Carvalho, Ivone,Rivera, Gildardo
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- Boron trifluoride-methanol complex. Mild and powerful reagent for deprotection of acetylated amines. Scope and selectivity
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A boron trifluoride-methanol complex demonstrated remarkable deprotection selectivity against commonly used amino-protecting groups in the deacetylation of acetanilides and high sensitivity to the steric hindrance of substrates. The scope and limitations of the reaction were explored.
- Miltsov, Sergey,Karavan, Vladimir,Misharev, Alexandr,Alonso-Chamarro, Julian,Puyol, Mar
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supporting information
p. 641 - 644
(2016/01/26)
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- Synthesis of Highly Functionalized 4-Aminoquinolines
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A diverse set of highly substituted 4-aminoquinolines was synthesized from ynamides, triflic anhydride, 2-chloropyridine, and readily accessible amides in a mild one-step procedure. Diverse products: Electrophilically activated amides easily react with sulfonyl ynamides to yield a diverse range of substituted 4-aminoquinolines. The ynamides can be easily modified by Sonogashira processes or generated from dichloroenamide precursors. Any substituent can thus be introduced at the C3 position of the quinoline. 2-ClPy=2-chloropyridine, Tf2O=triflic anhydride.
- Wezeman, Tim,Zhong, Sabilla,Nieger, Martin,Br?se, Stefan
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supporting information
p. 3823 - 3827
(2016/04/05)
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- Palladium-Catalyzed C-H Activation and Cyclization of Anilides with 2-Iodoacetates and 2-Iodobenzoates: An Efficient Method toward Oxindoles and Phenanthridones
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A concise approach to the synthesis of oxindoles and phenanthridones from anilides is described. In the presence of catalytic amount of Pd(OAc)2, 2-iodoacetates and 2-iodobenzoates can be used to functionalize ortho C-H bond of anilides, which subsequently undergo intramolecular cyclization to give the products. A possible reaction mechanism that involves a PdII/PdIV catalytic cycle is proposed with the support of detailed mechanistic studies.
- Gandeepan, Parthasarathy,Rajamalli, Pachaiyappan,Cheng, Chien-Hong
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p. 1872 - 1879
(2016/06/15)
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- Synthesis of secondary amides from N-Substituted amidines by tandem oxidative rearrangement and isocyanate elimination
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In this work an efficient tandem process transforming N-substituted amidines into secondary amides has been described. The process involves N-acylurea formation by reaction of the substrate with bis(acyloxy)(phenyl)-λ3-iodane followed by isocyanate elimination. The periodinane reagents are obtained from the commercially available phenyl-iodine(III) diacetate [PhI(OAc)2, (PIDA)] by ligand exchange with carboxylic acids. The N-substituted amidine substrates are easily synthesized from readily available nitriles. The method is applicable for secondary amide synthesis, based on both aliphatic and (hetero)aromatic amines, including challenging amides consisting of sterically hindered acids and amines. Moreover, the protocol allows one to combine steric bulk with electron deficiency in the target amides (aniline based). Such compounds are difficult to synthesize efficiently based on classical condensation reactions involving carboxylic acids and amines. Overall, the synthetic protocol transforms a nitrile into a secondary amide in both aliphatic and (hetero)aromatic systems.
- Debnath, Pradip,Baeten, Mattijs,Lefvre, Nicolas,Van Daele, Stijn,Maes, Bert U. W.
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supporting information
p. 197 - 209
(2015/03/03)
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- Transition metal-free intermolecular a-C-H amination of ethers at room temperature
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We describe a new method for the intermolecular amination of the α-C-H bonds of ethers. A hypervalent iodine reagent was used as oxidant to enable the amination of cyclic and acyclic alkyl ethers with a wide range of amides, imides, and amines. The amination occurred at room temperature and without a transition metal catalyst. The method could be used to synthesize the anti-cancer prodrug Tegafur and its analogues.
- Buslov, Ivan,Hu, Xile
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supporting information
p. 3325 - 3330
(2015/02/02)
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- Dimethyl sulfoxide participant iron-mediated cascade oxidation/α-formylation reaction of substituted 2,3-dihydropyrroles under air and protonic acid free condition
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An efficient and Bronsted acid free one-pot protocol to directly generate structurally sophisticated α-formylpyrrole derivatives in moderate to good yields has been demonstrated, involving an iron-mediated domino oxidation/formylation reaction of readily available 2,3-dihydro-1H-pyrroles in dimethyl sulfoxide and air atmosphere, in which dimethyl sulfoxide acts as the formyl donor. A possible mechanism is presented.
- Zhang, Zhiguo,Tian, Qing,Qian, Jingjing,Liu, Qingfeng,Liu, Tongxin,Shi, Lei,Zhang, Guisheng
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p. 8182 - 8188
(2015/03/18)
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- New compounds, pharmaceutical compositions and uses thereof
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The present invention relates to compounds of general formula I, wherein the groups R1, LP, LQ, Ar, m and n are as defined in the application, which have valuable pharmacological properties, and in particular bind to the GPR119 receptor and modulate its activity.
- -
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Paragraph 0367; 0368
(2013/03/28)
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- N- CYCLOPROPYL - N- PIPERIDINYLBENZAMIDES AS GPR119 MODULATORS
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The present invention relates to compounds of general formula I, wherein the groups R1, LP, LQ, Ar, mand n are as defined in the application, which have valuable pharmacological properties, and in particular bind to the GPR119 receptor and modulate its activity.
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Page/Page column 88
(2012/10/07)
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- Continuous flow synthesis of secondary amides by tandem azidation-amidation of anilines
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The continuous flow synthesis of a variety of secondary amides by tandem azidation-amidation of anilines is described. This new procedure benefits from the improved safety feature of generating aromatic azides in flow, thus ensuring low concentrations of any potentially hazardous intermediates. The protocol was amenable to the production of multi-gram quantities of the amide product. Georg Thieme Verlag Stuttgart · New York.
- Spiteri, Christian,Moses, John E.
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experimental part
p. 1546 - 1548
(2012/08/07)
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- Palladium-catalyzed oxidative C-H bond coupling of steered acetanilides and aldehydes: A facile access to ortho -acylacetanilides
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A palladium-catalyzed oxidative C-H bond functionalization/ortho-acylation of acetanilides using easily accessible aldehyde as the acyl source is described. In the presence of a Pd(TFA)2 catalyst and tert-butylhydroperoxide at 90 °C in general, an array of ortho-acylacetanilides can be afforded in good yields.
- Wu, Yinuo,Li, Baozhu,Mao, Fei,Li, Xingshu,Kwong, Fuk Yee
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supporting information; experimental part
p. 3258 - 3261
(2011/08/05)
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- Amidation of aryl halides catalyzed by the efficient and recyclable Cu 2O nanoparticles
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Cu2O nanoparticles/DMEDA (N,N′-dimethylethylenediamine) was proved to be an efficient catalyst system for amidation of aryl halides under mild condition. This method displayed excellent selectivity and the catalyst was recyclable without loss of activity. The low cost, simple operation and excellent yields make this approach attractive for industrial applications. Cu2O nanoparticles/DMEDA (N,N′-dimethylethylenediamine) was proved to be an efficient catalyst system for amidation of aryl halides under mild condition. This method displayed excellent selectivity and the catalyst was recyclable without loss of activity. The low cost, simple operation and excellent yields make this approach attractive for industrial applications. Copyright
- Yao, Zijian,Wei, Xianwen
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experimental part
p. 2260 - 2268
(2011/10/12)
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- NPY ANTAGONISTS, PREPARATION AND USES
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The present invention concerns novel compounds, their preparation and their uses, therapeutic uses in particular. More specifically it concerns derivative compounds having at least two aromatic cycles, their preparation and their uses, in particular in the area of human or animal health. These compounds have an affinity for the biological receptors of neuropeptide Y, NPY, present in the central and peripheral nervous systems. The compounds of the invention are preferably NPY antagonists, and more particularly antagonists of sub-type NPY Y1, and can therefore be used for the therapeutic or prophylactic treatment of any disorder involving NPY. The present invention also concerns pharmaceutical compositions containing said compounds, their preparation and their uses, as well as treatment methods using said compounds.
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Page/Page column 76
(2009/09/28)
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- Microwave-assisted synthesis of amide under solvent-free conditions
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An efficient and environmentally friendly synthetic method for the synthesis of primary amides under microwave irradiation was described, in which the primary amine was directly reacted with acid without any catalytic agents. The reaction took place in 8-12-min, which was much shorter than the traditional synthetic methods, with almost quantitative yields. The influential factor of the reaction was discussed. The tautomerization between the carboxylic acid group and the H atom in α-carbon of L-amino acid was observed, presumably a dehydrated intermediate forming from this tautomerized isomer. Copyright Taylor & Francis Group, LLC.
- Wang, Xiao-Jian,Yang, Qian,Liu, Fei,You, Qi-Dong
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p. 1028 - 1035
(2008/09/18)
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- Aryl halide tolerated electrophilic amination of arylboronic acids with N-chloroamides catalyzed by CuCl at room temperature
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(Chemical Equation Presented) N-Cl is no competition: Aryl halides were tolerated in an efficient ligandless CuCl-catalyzed electrophilic amination reaction of arylboronic acids with N-chloroamides (see scheme; Ac=acetoxy). This coupling proceeded smoothly at ambient temperature, and products were obtained with good to excellent yields.
- He, Chuan,Chen, Chong,Cheng, Jin,Liu, Chao,Liu, Wei,Li, Qiang,Lei, Aiwen
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body text
p. 6414 - 6417
(2009/03/11)
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- Electrochemical nuclear acetamidation of aromatic compounds at the platinum anode
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The electrochemical nuclear acetamidation of aromatic compounds ethylbenzoate, acetophenone, benzoic acid and benzene have been carried out at platinum anode under the process of nuclear oxidation. The removal of electrons from the aromatic π-electron system is achieved by the electrochemical oxidation. The electrolysis is carried out at the constant anode potential in an electrolytic cell assembly containing reaction mixture and electrodes. The products 4-acetamidoethylbenzoate, 4-acetamidoacetophenone, 4-acetamidobenzoic acid and N-phenylacetamide formed during the electrolysis are reported here.
- Sharma, Laxmi Kant,Kumar, Sanjeev,Yadav, Pragati,Singh
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p. 1277 - 1280
(2008/12/23)
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- N-THIAZOL-2-YL-BENZAMIDE DERIVATIVES
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The invention relates to N-thiazol-2-yl-benzamide derivatives of the formula I in the description wherein the variables are as defined in the claims. The compounds are A2A-receptor ligands, such as antagonists, agonists, reverse agonists or partial agonists, and are useful in the treatment of neurological and psychiatric disorders where an A2A-receptor is implicated.
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Page/Page column 22
(2008/06/13)
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- A simple and efficient method for reductive acylation of azides using aluminium iodide and acetic anhydride
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A combination of aluminium iodide and acetic anhydride effectively converts a variety of azides to their corresponding acetamides in good to excellent yields without perturbing many active functionalities such as ether, ester, nitro etc.
- Bez, Ghanashyam
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p. 3625 - 3628
(2007/10/03)
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- A novel one-pot method for reductive conversion of azides to acyl amines with acetic anhydride and trimethyl chlorosilane
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A combination of acetic anhydride and chloro-trimethylsilane has been shown to effect the conversion of a variety of azides to the corresponding acetylated amines in excellent yields without affecting other functional groups such as ether, ester, halide etc.
- Barua, Apurba,Bez, Ghanashyam,Barua, Nabin C.
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p. 553 - 554
(2007/10/03)
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- Synthesis of 2,5-disubstituted 1,3,4-oxadiazoles as potential antimicrobial, anticancer and anti-HIV agents
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Several 2-(N-substituted carboxamidomethylthio)-5-(4-acetylaminophenyl)-l,3,4-oxadiazoles 4 a-s have been synthesized and tested for their antibacterial, antitubercular, anticancer and anti-HIV activities. The structures of these compounds have been estab
- Shah,Shah,Bhatt,Desai,Trivedi,Undavia
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p. 180 - 182
(2007/10/03)
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- Retention behavior of compounds with active hydrogen atoms and their acetylated derivatives in reversed-phase HPLC
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In view of poor interlaboratory reproducibility of retention indices I in reversed-phase high-performance liquid chromatography, not the indices themselves but their differences for reactants and products of interaction with various reagents can be used to identify compounds with active hydrogen atoms. For acetylated derivatives of phenols and aromatic amines, the quantity ?I = I(ArXH) -I(ArXCOCH3), where X = O or NH. has statistically significant distinguishable values of 126 ± 15 and 70 ± 20, respectively. The additivity of the parameters ?I is first revealed for the polyfunctional compounds of these classes that are incapable of intramolecular hydrogen bonding. Abnormal ?I values and deviations from the additivity rule are observed only for substances with intramolecular hydrogen bonding. This finding can be used to confirm the presence of relevant structural units in molecules.
- Zenkevich,Kosman
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p. 1173 - 1176
(2007/10/03)
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- Hypoxia-Selective Agents Derived from Quinoxaline 1,4-Di-N-oxides
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Hypoxic cells, which are a common feature of solid tumors, but not normal tissues, are resistant to both anticancer drugs and radiation therapy.Thus the identification of drugs with selective toxicity toward hypoxic cells is an important objective in anticancer chemotherapy.The benzotriazine di-N-oxide (SR 4233, Tirapazamine) has been shown to be an efficient and selective cytotoxin for hypoxic cells.Since the bioreductive activation of Tirapazamine is thought to be due to the presence of the 1,4-di-N-oxide moiety, a series of 3-aminoquinoxaline-2-carbonitrile 1,4-di-N-oxides with a range of electron-donating and -withdrawing substituents in the 6- and /or 7- positions has been synthesized and evaluated for toxicity to hypoxic cells.Electrochemical studies of the quinoxaline di-N-oxides and Tirapazamine showed that as the electron-withdrawing nature of the 6(7)-substituent increases, the reduction potential becomes more positive and the compound is more readily reduced.Apart from the unsubstituted 6a and the 6,7-dimethyl derivative 6c, the quinoxaline di-N-oxide have reduction potentials significantly more positive than Tirapazamine (Epc -0.90 V).The most potent cytotoxins to cells in culture were the 6,7-dichloro and 6,7-difluoro derivatives 6i and 6l, which were 30-fold more potent than Tirapazamine.The 6(7)-fluoro and 6(7)-chloro compounds, 6e and 6h, showed the greatest hypoxia selectivity.Four of the compounds, 6e, 6f, 6h and 6i, killed the inner cells of multicellular tumor spheroids in vitro.In vivo Balb/c mice tolerated a dose of these four compounds twice the size of that of Tirapazamine.This study demonstrates that quinoxaline 1,4-di-N-oxides could provide useful hypoxia-selective therapeutic agents.
- Monge, Antonio,Palop, Juan A.,Cerain, Adela Lopez de,Senador, Virginia,Martinez-Crespo, Francisko J.,et al.
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p. 1786 - 1792
(2007/10/02)
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