Search results for "Imidazoli"

Characterization of sensory neurotransmission and its inhibition via alpha 2B-adrenoceptors and via non-alpha 2-receptors in rabbit iris.

1993

To find out whether, and which type of, adrenoceptors mediate prejunctional inhibition of sensory neurotransmitter release from trigeminal fibres, the modulation of twitch response to electrical field stimulation on rabbit isolated iris was investigated. Evoked iris sphincter contractions consisted of a minor fast cholinergic and a large slow component. The latter was unaffected by atropine and guanethidine, hence nonadrenergic noncholinergic in nature (NANC), but nearly completely abolished by capsaicin pretreatment and by the neurokinin receptor antagonist spantide. The response was probably not mediated by NK2 receptors as SR 48,968, an NK2 selective nonpeptide antagonist, failed to redu…

Synthesis, Structure and Anion Sensing Properties of a Dicationic Bis(imidazolium)-Based Cyclophane

2018

The preparation and sensing properties of a tetracyclic cyclophane receptor containing two imidazolium rings as anion binding sites and two fluorene rings as fluorescent signaling units, are reported. The receptor behaves as a selective fluorescent chemosensor molecule for inorganic phosphates. H-NMR spectroscopical data clearly indicate the simultaneous occurrence of charge-assisted aromatic and aliphatic C−H noncovalent interactions. PCM/DFT calculations have been carried out to predict the structures of the complexes formed with one and two molecules of PF , HPO and HPO .

Structure of chloroantimonates(III) with an imidazolium cation: (C3H5N2)[SbCl4] and (C3H5N2)2[SbCl5]

2003

Abstract Two different chloroantimonates(III) with an imidazolium cation have been synthesized by the reaction of antimony trichloride and imidazole in an aqueous solution of hydrochloric acid. The crystals of (C3H5N2)[SbCl4] are monoclinic, space group C2/c, while (C3H5N2)2[SbCl5] crystallizes in the orthorhombic system, space group Pbcn. Both crystals are built of one dimensional zig-zag chains composed of [SbCl6]3− octahedra connected by edges and corners, respectively. The cavities between inorganic chains are filled by imidazolium cations. In both structures, one crystallographically independent imidazolium cation is rotationally disordered, and the positions of all atoms are split bet…

The influence of electron delocalization upon the stability and structure of potential N-heterocyclic carbene precursors with 1,3-diaryl-imidazolidin…

2010

Targeting N-heterocyclic carbenes (NHCs) with increased π-acceptor character featuring N-fluorophenyl substituents, the molecular 2-chloro-1,3-bis(fluorophenyl)imidazolidine-4,5-diones (1a–c) were isolated from the condensation of the corresponding formamidine with oxalyl chloride. These formal adducts of NHCs with hydrogen chloride demonstrated reactivity akin to that of alkyl halides: 1,3,1′,3′-tetrakis(2,6-dimethylphenyl)-[2,2′]diimidazolidinyl-4,5,4′,5′-tetraone (2b) was formed via the reductive coupling of 1b, while 1,3-bis(2,6-diisopropylphenyl)-4,5-dioxoimidazolidin-2-yl acetate (3c) was formed as the result of a metathesis reaction with mercury(II) acetate. Chloride abstraction resu…

1H, 13C and 15N NMR spectral characterization of twenty-seven 1,2-diaryl-(4E)-arylidene-2-imidazolin-5-ones.

2006

1H, 13C and 15N NMR chemical shifts and couplings nJ(H,C) in DMSO-d6 at 30 °C have been determined for 1,2-diaryl-(4E)-arylidene-2-imidazolin-5-one derivatives 1–27. Their chemical shift assignments are based on PFG DQF 1H,1H COSY, PFG 1H,13C HMQC as well as PFG 1H,13C and 1H,15N HMBC experiments. For compounds 1–10 including aryl fluorine substituent(s) also the couplings nJ(F,C) (n = 1 − 4) are reported. Copyright © 2006 John Wiley & Sons, Ltd.

DICATIONIC IMIDAZOLIUM SALTS: TUNABLE ANTIMICROBIAL AND ANTITUMORAL CHEMIOTHERAPEUTIC LEADS

2015

The chemical synthesis of novel chemotherapeutical leads is evolving thanks to possibility to design molecules with desired physical-chemical and, thus, biological properties. The imidazolium salts, recently proven effective to inhibit bacterial and/or cancer cell growth, posses an amphiphilic nature that is conferred by the imidazolium cation having a polar head generally coupled with aliphatic side chains. Thus, biological properties of imidazolium salts can be tuned through modifications involving the cation structure and/or the anion nature. By covalently linking two imidazolium rings, di-imidazolium salts were obtainedobtain differing in: i) kind of anions; ii) geometric isomerization …

Two components hydrogels formed by host-guest interactions

Diimidazolium-based supramolecular ionogels for dye removal from wastewaters

Functionalized Diatonic Ionic Liquids Applied to the Study of Michael Addition

Development of eco-friendly processes for the synthesis of biobased solvents and organocatalysts

2018

Oxazolidinones are promising compounds for industrial applications, but nowadays there is not convenient method to produce them on large scale, because of the use of reactants and metallic catalysts harmful for health and environment. A new synthesis method of these compounds was thus elaborated using aminoalcohols and diethyl carbonate. This reaction is catalysed by a biobased imidazolium hydrogen carbonate which is produced by an electrochemical pathway in order to reduce its impact on the environment.This oxazolidinones synthesis method was then applied to the synthesis of a biobased oxazolidinone. To achieve this, an aminoalcohol synthesis was realised, and its structure was established…