- ELECTRONIC STRUCTURE OF ALKYLATED IMIDAZOLES AND ELECTRONIC SPECTRA OF TETRAKIS(IMIDAZOLE)COPPER(II) COMPLEXES. MOLECULAR STRUCTURE OF TETRAKIS(1,4,5-TRIMETHYLIMIDAZOLE)COPPER(II) DIPERCHLORATE.
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The synthesis, crystal structure, electronic spectra, and ESR spectra are reported for the title complex (1). Energies of the molecular orbitals and electronically excited states of imidazole and of several methylated imidazoles have been calculated. Ligand to metal charge-transfer (LMCT) absorptions of the title complex and other Cu(II)-imidazole complexes are discussed and compared. preliminary LMCT spectra are presented for the yellow diamagnetic tetrakis(1,2-dimethylimidazole)nickel(II) diperchlorate complex and its Cu(II) analogue. An experimental justification for assigning the charge-transfer absorptions as LMCT instead of MLCT is presented.
- Bernarducci,Bharadwaj,Krogh-Jespersen,Potenza,Schugar
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- MACROCYCLIC AZOLOPYRIDINE DERIVATIVES AS EED AND PRC2 MODULATORS
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The invention relates to modulators of Embryonic Ectoderm Development (EED) and/or Polycomb Repressive Complex 2 (PRC2) useful in the treatment of disorders and diseases associated with EEC and PRC2, being macrocyclic azolopyridine derivatives and compositions thereof of Formula (I), or a pharmaceutically acceptable salt, prodrug, solvate, hydrate, enantiomer, isomer, or tautomer thereof, wherein X1, X2, X3, A1, A2, Y, R1, R2, R3, and R4 are as described herein.
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Paragraph 1123
(2020/10/09)
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- Syntheses of polyalkylated imidazoles
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We have developed improved general simple methods for large-scale preparation of polyalkylated imidazoles by improved multicomponent synthesis from commercially available starting materials. A large range of NH- and N-alkyl-polyalkylimidazoles (40 in total, including novel compounds) has been synthesized.
- Evjen, Sigvart,Fiksdahl, Anne
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supporting information
p. 1392 - 1399
(2017/07/25)
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- Synthesis of optically active polyheterocycles containing pyrrolidine, imidazole, and 1,2,3-triazole rings
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Optically active polyheterocycles containing pyrrolidine, imidazole, and 1,2,3-triazole units were obtained via a multistep synthesis with the [3+2] cycloaddition of Boc-protected (S)-(pyrrolidin-2-yl)methyl azide with 2-ethynylimidazoles in the presence of CuI (CuAAC reaction) as the key step. Typical for terminal alkynes, the reactions occurred regioselectively and 1,4-disubstituted 1,2,3-triazoles were formed exclusively. The deprotection of the pyrrolidine N-atom was performed by treatment with TFA under standard conditions.
- Wróblewska, Aneta,Mlostoń, Grzegorz,Heimgartner, Heinz
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p. 1448 - 1452
(2015/12/09)
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- Asymmetric Copper(II)-catalysed nitroaldol (Henry) reactions utilizing a chiral C1-symmetric dinitrogen ligand
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A series of stable chiral C1-symmetric dinitrogen ligands were conveniently synthesized in high yields by condensation of chiral amines [(-)-exo-bornylamine or (+)-(1S,2S,5R)-menthylamine] with various substituted imidazolecarbaldehydes. With the assistance of base, the ligand L1 in combination with CuCl2·2H2O (2.5 mol-% or 5.0 mol-%) can efficiently promote nitroaldol (Henry) reactions between a variety of aldehydes and nitromethane. Both aromatic and aliphatic aldehydes were tolerated in our catalytic system, affording the expected nitroalcohol products in high yields (up to 97%) and with good enantioselectivities (up to 96%) under mild reaction conditions. A series of chiral C1-symmetric dinitrogen ligands were conveniently synthesized in high yields by condensations of chiralamines with various substituted imidazolecarbaldehydes. The ligand L1 in conjunction with CuCl2·2H2O can efficiently promote nitroaldol (Henry) reactions between various aldehydes and nitromethane in high yields (up to 97%) and with good enantioselectivities (up to 96%).
- Zhou, Yirong,Gong, Yuefa
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experimental part
p. 6092 - 6099
(2011/11/29)
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- METHODS OF USING DIHYDROPYRIDOPHTHALAZINONE INHIBITORS OF POLY (ADP-RIBOSE)POLYMERASE (PARP)
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Provided herein are methods of treating cancer comprising administering a topoisomerase inhibitor, temozolomide, or a platin in combination with a Compound of Formula (I) or Formula (II), where the substituents Y, Z, A, B, R1, R2, R3, R4 and R5 are as defined herein.
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Page/Page column 150
(2011/11/01)
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- DIHYDROPYRIDOPHTHALAZINONE INHIBITORS OF POLY(ADP-RIBOSE)POLYMERASE (PARP)
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A compound having the structure set forth in Formula (I) and Formula (II): wherein the substituents Y, Z, A, B, R1, R2, R3, R4 and R5 are as defined herein. Provided herein are inhibitors of poly(ADP-ribose)polymerase activity. Also described herein are pharmaceutical compositions that include at least one compound described herein and the use of a compound or pharmaceutical composition described herein to treat diseases, disorders and conditions that are ameliorated by the inhibition of PARP activity.
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Page/Page column 78-79
(2010/03/02)
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- On the electronic impact of abnormal C4-bonding in n-heterocyclic carbene complexes
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Sterically similar palladium dicarbene complexes have been synthesized that comprise permethylated dicarbene ligands which bind the metal center either in a normal coordination mode via C2 or abnormally via C4. Due to the strong structural analogy of the complexes, differences in reactivity patterns may be attributed to the distinct electronic impact of normal versus abnormal carbene bonding, while stereoelectronic effects are negligible. Unique reactivity patterns have been identified for the abnormal carbene complexes, specifically upon reaction with Lewis acids and in oxidative addition-reductive elimination sequences. These reactivities as well as analytical investigations using X-ray diffraction and X-ray photoelectron spectros-copy indicate that the C4 bonding mode increases the electron density at the metal center substantially, classifying such C4-bound carbene ligands amongst the most basic neutral donors known thus far. A direct application of this enhanced electron density at the metal center is demonstrated by the catalytic H2 activation with abnormal carbene complexes under mild conditions, leading to a catalytic process for the hydrogenation of olefins.
- Heckenroth, Marion,Neels, Antonia,Garnier, Michael G.,Aebi, Philipp,Ehlers, Andreas W.,Albrecht, Martin
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experimental part
p. 9375 - 9386
(2010/04/02)
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- Kinetics and mechanism of the nucleophilic cleavage of disulfide bond in 2,2′-dithio-diimidazoles with hydroxide ions
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Kinetics of the cleavage of disulfide bond of dithiobisdisulfides of diimidazoles to their parent imidazoles by hydroxide ion have been investigated spectrophotometrically. Rate equation and other observations suggest that the nucleophilic attack of hydroxide ion on one of the sulfur atoms of disulfide bond is a rate limiting step. This process is accompanied by much slower, parallel reaction with water as a nucleophile. Hence the full kinetic equation for nucleophilic cleavage of 2,2′-dithio-diimidazoles in aqueous alkaline solutions is a two-term equation: -(d[RSSR]/dt) = k1 [RSSR][OHl + k2[RSSR][H2O], where k1 > k2. The mechanism of the reaction is proposed.
- Kurzawa,Suszka
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p. 1487 - 1494
(2008/09/18)
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- An acidity scale of 1,3-dialkylimidazolium salts in dimethyl sulfoxide solution
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(Chemical Equation Presented) Equilibrium acidities of 16 1,3-dialkylimidazolium-type ionic liquid (IL) molecules (1-16) were systematically measured by the overlapping indicator method at 25°C in dimethyl sulfoxide (DMSO) solution. The pKa values were observed to range from 23.4 for IL 12 to 19.7 for IL 6 (Tables 1 and 2), responding mainly to structural variations on the cation moiety. Excellent agreement between the spectrophotometrically determined pKa and that derived from NMR titration for 1,3,4,5-tetramethylimidazolium bis(trifluoromethanesulfonyl)imide (12) and the close match of the obtained pK values with the reported data in literature provide credence to the acidity measurements of the present work. The substituent effects at the imidazolium ring and the effects of counterions on the acidities of ionic liquids are discussed.
- Chu, Yuan,Deng, Hui,Cheng, Jin-Pei
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p. 7790 - 7793
(2008/02/13)
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- Process for manufacture of imidazoles
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Imidazoles may be manufactured by reacting a glyoxal, ammonia, an aldehyde, and optionally a primary amine, in the presence of a Bronsted acid whose pKa is approximately equal to the pKa of the ammonium cation of the primary amine, or if the primary amine is not present, to the pKa of the ammonium (NH4+) cation. The reaction may be used to make in relatively high yields a wide variety of imidazoles using relatively inexpensive starting materials. The imidazoles are useful as chemical intermediates.
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- A direct synthetic approach to novel quadrupolar [14]azolophanes
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A convergent '3+1' synthesis allowed a simple entrance to the first examples of [14]metaazolophanes 1 and [14l(meta-ortho)2azolophanes 2 built up from heterocyclic betaine subunits, illustrating a prototype of phanes constructed by both highly π-excessiveand highly π-deficient heteroaromatic moieties linked in a 1,3-alternating fashion.
- Alcalde, Ermitas,Alemany, Montserrat,Gisbert, Maria
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p. 15171 - 15188
(2007/10/03)
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- Preparation of 1-substituted imidazoles
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A process for the preparation of 1-substituted imidazoles by reacting an α-dicarbonyl compound with ammonia, an aldehyde and a primary amine in an aqueous medium, in a single stage, at 20°-150° C.
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