Puzzling formation of bisimidazole derivatives from hexachloroacetone and diamines

Gehüpft wie gesprungen: Eine niederenergetische Bande im Absorptionsspektrum des oxidierten Watson‐Crick‐Komplexes von Guanosin‐ und Cytidinderivaten wurde detektiert (siehe Schema) und dem Ladungstransfer zugeschrieben, der das Elektronenloch im oxidierten Cytidinrest lokalisiert. Damit lässt sich die Energie eines der niedrigen elektronischen Zustände von oxidierter Doppelstrang‐DNA abschätzen.

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“…13 C NMR spectra also confirm the formation of 8‐8 bipurinyl compounds on the basis of existing data 20. 21…”

Section: Predicted and Observed Wavenumbers [Cm−1] For The Ct Band Ofmentioning

confidence: 54%

The Charge‐Transfer Band of an Oxidized Watson–Crick Guanosine–Cytidine Complex

et al. 2009

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“…1) were all prepared by following literature procedures and were isolated in reasonable yields and produced spectroscopic properties congruent with the literature results. [12][13][14] Coordination of neutral 1 was carried out in the absence of any external base by reaction with 0.25 equiv. of Co 4 (3,5-DBSQ) 8 (Pierpont's "tetramer").…”

Section: Resultsmentioning

confidence: 99%

Preparation, electrochemical behavior, and variable-temperature magnetic properties of Co(3,5-DBSQ)₂ complexes of imidazole- or pyrazole-substituted ligands

2015

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Herein we describe the preparation of four new Co(3,5-DBSQ) 2 containing known 2-(2-pyridyl)benzimidazole 1, 2,2=-bisbenzimidazole 2, or 2,2-(1H-pyrazole-3,5-diyl)dipyridine 3. We investigate the electronic and variable-temperature magnetic susceptibility properties of these complexes. Complexes containing 2 and 3 are bimetallic and variable-temperature magnetic susceptibility data suggest observation of a stable intermediate (high-spin and low-spin) state for the bimetallic complex with 3, which does undergo valence tautomerism. Complexes 4-6 containing imidazole-based ligands 1 and 2 feature high-spin ground states and no valence tautomerism is observed in these materials. This experimental finding is corroborated with density functional theory calculations, which support the existence of a stable high-spin ground state in these complexes. Résumé :Dans le présent article, nous décrivons la préparation de quatre nouveaux complexes de type Co(3,5-DBSQ) 2 dont les ligands connus sont le 2-(2-pyridyl)benzimidazole 1, le 2,2=-bis(benzimidazole) 2 ou la 2,2-(1H-pyrazole-3,5-diyl)dipyridine 3. Nous avons étudié ces complexes sous l'angle de leurs propriétés électroniques et de leurs propriétés de susceptibilité magnétique en fonction de la température. Les complexes comprenant les ligands 2 et 3 sont bimétalliques, et les données de susceptibilité magnétique en fonction de la température laissent supposer qu'on devrait observer un état intermédiaire stable (formes haut-spin et bas-spin) pour le complexe bimétallique avec le ligand 3, qui manifeste effectivement un tautomérisme de valence. Les complexes 4 à 6 comprenant les ligands à base d'imidazole 1 et 2 présentent des états fondamentaux de forme haut-spin, et aucun tautomérisme de valence n'est observé dans ces composés. Ce résultat expérimental est corroboré par des calculs de la théorie de la fonctionnelle de la densité, qui appuient l'existence d'un état fondamental stable de forme haut-spin dans ces complexes. [Traduit par la Rédaction]

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“…Ref. 24: 300 С). The structure of the synthesized compound was con firmed by elemental analysis and IR and NMR spectroscopic data.…”

Section: Bbimentioning

confidence: 95%

Effect of surfactant micelles on solubility and spectral characteristics of 2,2’-bibenzimidazole

et al. 2014

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The solubilization capacity of surfactants of different types was quantitatively characterized by spectrophotometry toward 2,2´ bibenzimidazole (BBI), whose derivatives possess a wide range of pharmacological activity. 2,2´ Bibenzimidazole solubilized by sodium dodecyl sulfate micelles is characterized by a high molar absorption coefficient (9400 mol -1 L cm -1 ) at the absorbance maximum (342 nm at pH 4-10), which may serve as a basis for the development of procedures for analytical monitoring of the BBI content in aqueous solutions and biosystems. The ability of surfactants to enhance the solubility of BBI in water and, as a consequence, to increase its bioavailability in the series sodium dodecyl sulfate < cetyltrimethylammonium bromide < Tween 80.

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Puzzling formation of bisimidazole derivatives from hexachloroacetone and diamines

Cited by 22 publications

References 11 publications

The Charge‐Transfer Band of an Oxidized Watson–Crick Guanosine–Cytidine Complex

The Charge‐Transfer Band of an Oxidized Watson–Crick Guanosine–Cytidine Complex

Preparation, electrochemical behavior, and variable-temperature magnetic properties of Co(3,5-DBSQ)₂ complexes of imidazole- or pyrazole-substituted ligands

Effect of surfactant micelles on solubility and spectral characteristics of 2,2’-bibenzimidazole

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Puzzling formation of bisimidazole derivatives from hexachloroacetone and diamines

Cited by 22 publications

References 11 publications

The Charge‐Transfer Band of an Oxidized Watson–Crick Guanosine–Cytidine Complex

The Charge‐Transfer Band of an Oxidized Watson–Crick Guanosine–Cytidine Complex

Preparation, electrochemical behavior, and variable-temperature magnetic properties of Co(3,5-DBSQ)2 complexes of imidazole- or pyrazole-substituted ligands

Effect of surfactant micelles on solubility and spectral characteristics of 2,2’-bibenzimidazole

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Preparation, electrochemical behavior, and variable-temperature magnetic properties of Co(3,5-DBSQ)₂ complexes of imidazole- or pyrazole-substituted ligands