- Spectroscopic studies of the intramolecular hydrogen bonding in o-hydroxy Schiff bases, derived from diaminomaleonitrile, and their deprotonation reaction products
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The structural study of five Schiff bases derived from diaminomaleonitrile (DAMN) and 2-hydroxy carbonyl compounds was performed using 1H, 13C and 15N NMR methods in solution and in the solid state as well. ATR-FTIR and X-Ray spectroscopies were used for confirmation of the results obtained by NMR method. The imine obtained from DAMN and benzaldehyde was synthesized as a model compound which lacks intramolecular hydrogen bond. Deprotonation of all synthesized compounds was done by treating with tetramethylguanidine (TMG). NMR data revealed that salicylidene Schiff bases in DMSO solution exist as OH forms without intramolecular hydrogen bonds and independent on the substituents in aromatic ring. In the case of 2-hydroxy naphthyl derivative, the OH proton is engaged into weak intramolecular hydrogen bond. Two of imines (salDAMN and 5-BrsalDAMN) exist in DMSO solution as equilibrium mixtures of two isomers (A and B). The structures of equilibrium mixture in the solid state have been studied by NMR, ATR-FTIR and X-Ray methods. The deprotonation of three studied compounds (salDAMN, 5-BrsalDAMN, and 5-CH3salDAMN) proceeded in two different ways: deprotonation of oxygen atom (X form) or of nitrogen atom of free primary amine group of DAMN moiety (Y form). For 5-NO2salDAMN and naphDAMN only one form (X) was observed.
- Szady-Che?mieniecka, Anna,Ko?odziej, Beata,Morawiak, Maja,Kamieński, Bohdan,Schilf, Wojciech
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p. 330 - 341
(2017/08/23)
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- One-pot oxidative Ugi-type three-component reaction of aromatic hydrocarbons of petroleum naphtha: comparing catalytic effect of cellulose- and wool-SO3H supported with manganese dioxide nanostructures
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A novel domino oxidative Ugi-type three-component reaction of aromatic hydrocarbons (OU-3CR) has been investigated with aromatic hydrocarbons of petroleum naphtha using two biopolymer supported MnO2 nanostructured catalysts, MnO2@cellulose-SO3H and MnO2@wool-SO3H, for the synthesis of α-amino amides, 3,4-dihydroquinoxalin-2-amine, 4H-benzo[b][1,4]thiazin-2-amine, and cyanophenylamino-acetamide derivatives. Nano-MnO2@cellulose-SO3H and nano-MnO2@wool-SO3H were used as biodegradable oxidation and solid acid catalysts. The best results for oxidation and condensation processes are obtained with MnO2@cellulose-SO3H and MnO2@wool-SO3H, respectively. To the best of our knowledge this approach can be considered as the first example of OU-3CR of alkyl arenes with a nano-MnO2 catalyst which would be very useful from a practical point of view.
- Shaabani, Ahmad,Hezarkhani, Zeinab,Badali, Elham
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p. 91966 - 91973
(2015/11/16)
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- Cellulose-SO3H as a biodegradable solid acid catalyzed one-pot three-component Ugi reaction: Synthesis of α-amino amide, 3,4-dihydroquinoxalin-2-amine, 4H-benzo[b][1,4]thiazin-2-amine and 1,6-dihydropyrazine-2,3-dicarbonitrile derivatives
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A variety of amines has become utilized in the three-compound Ugi reaction and synthesis of 3,4-dihydroquinoxalin-2-amine, 4H-benzo[b][1,4]thiazin-2-amine and 1,6-dihydropyrazine-2,3-dicarbonitrile derivatives in the presence of cellulose sulfuric acid as
- Mofakham, Hamid,Hezarkhani, Zeinab,Shaabani, Ahmad
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scheme or table
p. 26 - 34
(2012/08/13)
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- Discovery of cell-active phenyl-imidazole Pin1 inhibitors by structure-guided fragment evolution
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Pin1 is an emerging oncology target strongly implicated in Ras and ErbB2-mediated tumourigenesis. Pin1 isomerizes bonds linking phospho-serine/threonine moieties to proline enabling it to play a key role in proline-directed kinase signalling. Here we report a novel series of Pin1 inhibitors based on a phenyl imidazole acid core that contains sub-μM inhibitors. Compounds have been identified that block prostate cancer cell growth under conditions where Pin1 is essential.
- Potter, Andrew,Oldfield, Victoria,Nunns, Claire,Fromont, Christophe,Ray, Stuart,Northfield, Christopher J.,Bryant, Christopher J.,Scrace, Simon F.,Robinson, David,Matossova, Natalia,Baker, Lisa,Dokurno, Pawel,Surgenor, Allan E.,Davis, Ben,Richardson, Christine M.,Murray, James B.,Moore, Jonathan D.
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scheme or table
p. 6483 - 6488
(2010/12/18)
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- Synthesis and Tritium Radiolabelling of Fluorinated Analogues of myo-Inositol
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Syntheses have been developed for a set of six myo-inositol analogues from myo-inositol in which single hydroxy groups have been replaced by fluorine (monodeoxy-fluoro-myo-inositols).Except for 2-deoxy-2-fluoro-myo-inositol 32 and 1D-4-deoxy-4-fluoro-myo-
- Offer, John L.,Voorheis, H. Paul,Metcalfe, James C.,Smith, Gerry A.
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p. 953 - 960
(2007/10/02)
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- SYNTHESIS OF IMINES FROM N-(1-HALOGENOALKYL)HETEROARYLIUM SALTS
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A comparison is established for the reactivity of benzaldehyde, N-(1-chlorobenzyl)pyridinium chloride or N-(1-chlorobenzyl)pyrimidinium chloride with several poorly nucleophilic and/or poorly soluble primary amines under mild experimental conditions.
- Maquestiau, A.,Anders, E.,Eynde, J.-J. Vanden,D'Orazio, P.,Mayence, A.
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p. 523 - 528
(2007/10/02)
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- Hydrogen Cyanide Chemistry. 9. Cycloaddition Reactions and Nitrenium Ion Type Reactivity of Diiminosuccinonitrile
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Cycloaddition reactions of diiminosuccinonitrile (DISN) with nucleophilic olefins yield a variety of products including cycloadducts and aziridines.All of the products derived from 1,3-dienes, styrene, para-substituted styrenes, cycloheptatriene, norbornene, and norbornadiene can be accounted for by rearrangements of a common intermediate, zwitterionic aziridinium ion.We introduce the concept of reverse polarization and propose that DISN is a latent nitrenium ion source (isoelectronic with carbenes) and that reverse polarization of one of the >C=N bonds of DISNis responsible for the observed reactions.Comments are made on reverse polarization of other >C=X bonds, and facile 1,1-cycloreversion of aziridines is also reported.
- Fukunaga, Tadamichi,Begland, Robert W.
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p. 813 - 821
(2007/10/02)
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