A naphthoimidazolium-cholesterol derivative as a ratiometric fluorescence based chemosensor for the chiral recognition of carboxylates

We report a naphthoimidazolium-cholesterol derivative (NI-chol 1) as a fluorescence based chemosensor for chiral recognition via imidazolium (C–H)+–anion binding.

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A ratiometric fluorescence chemosensor based on a coumarin–pyrazolone hybrid: the synthesis and an investigation of the photophysical, tautomeric and anion binding properties by spectroscopic techniques and DFT calculations

Tetrahedron Letters ◽

10.1016/j.tetlet.2015.03.014 ◽

2015 ◽

Vol 56 (17) ◽

pp. 2149-2154 ◽

Cited By ~ 23

Author(s):

Banu Babür ◽

Nurgül Seferoğlu ◽

Zeynel Seferoğlu

Keyword(s):

Dft Calculations ◽

Anion Binding ◽

Spectroscopic Techniques ◽

Ratiometric Fluorescence ◽

Binding Properties

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Influence of the size and geometry of the anion binding pocket of sugar–urea anion receptors on chiral recognition

Tetrahedron Letters ◽

10.1016/j.tetlet.2013.08.019 ◽

2013 ◽

Vol 54 (41) ◽

pp. 5608-5611 ◽

Cited By ~ 17

Author(s):

Paulina Hamankiewicz ◽

Jarosław M. Granda ◽

Janusz Jurczak

Keyword(s):

Chiral Recognition ◽

Binding Pocket ◽

Anion Binding ◽

Anion Receptors

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Ratio imaging of intracellular ion concentration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130432 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1160-1161

Author(s):

Stephen R. Bolsover

Keyword(s):

Individual Cell ◽

Video Camera ◽

Field Of View ◽

Ion Concentration ◽

Fluorescence Signal ◽

Ion Imaging ◽

Ratiometric Fluorescence ◽

Ratio Imaging ◽

The Mean ◽

The Many

The field of intracellular ion concentration measurement expanded greatly in the 1980's due primarily to the development by Roger Tsien of ratiometric fluorescence dyes. These dyes have many applications, and in particular they make possible to image ion concentrations: to produce maps of the ion concentration within living cells. Ion imagers comprise a fluorescence microscope, an imaging light detector such as a video camera, and a computer system to process the fluorescence signal and display the map of ion concentration.Ion imaging can be used for two distinct purposes. In the first, the imager looks at a field of cells, measuring the mean ion concentration in each cell of the many in the field of view. One can then, for instance, challenge the cells with an agonist and examine the response of each individual cell. Ion imagers are not necessary for this sort of experiment: one can instead use a system that measures the mean ion concentration in a just one cell at any one time. However, they are very much more convenient.

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The Ability of Thrombin Inhibitors to Reduce the Thrombin Activity Generated in Plasma on Extrinsic and Intrinsic Activation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655996 ◽

1997 ◽

Vol 77 (03) ◽

pp. 498-503 ◽

Cited By ~ 26

Author(s):

D Prasa ◽

L Svendsen ◽

J Stürzebecher

Keyword(s):

Active Site ◽

Thrombin Generation ◽

Anion Binding ◽

Thrombin Inhibitors ◽

Coagulation System ◽

Thrombin Activity ◽

Continuous Registration ◽

High Concentrations ◽

20 Nm ◽

Generation Test

SummaryIn a thrombin generation test with continuous registration of thrombin activity in plasma we studied the ability of a variety of thrombin inhibitors of different type and mechanism of action to influence the activity of thrombin after activation of the coagulation system. Depending on the inhibitor, the peak of thrombin activity is delayed and/or reduced.By blocking the active site of generated thrombin inhibitors cause a concentration dependent reduction of the thrombin peak and inhibit feed-back reactions of thrombin resulting in a delay of thrombin generation. Highly potent synthetic active-site directed inhibitors (Ki ≤ 20 nM) reduce the thrombin activity formed in plasma after extrinsic or intrinsic activation with the same efficiency (IC50 0.1 - 0.6 μM) as hirudin. The delay and reduction of thrombin generation by inhibitors of the anion-binding exosite 1 of thrombin is only attributed to an inhibition of feed-back reactions of thrombin. For a 50% reduction of thrombin activity in plasma by this type of inhibitors relatively high concentrations were determined.

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Cambiarenes: Single-Step Synthesis and Anion Binding of a Clip- Shaped Macrocycle with a Redox-Active Core

10.26434/chemrxiv.9795005.v1 ◽

2019 ◽

Author(s):

Riley J. Petersen ◽

Brett J. Rozeboom ◽

Shalisa Oburn ◽

Nolan Blythe ◽

Tanner Rathje ◽

...

Keyword(s):

Electron Density ◽

Single Step ◽

Anion Binding ◽

Host Molecule ◽

Selective Binding ◽

The Core ◽

Redox Active ◽

Active Core ◽

Guest Binding

<div>We report the synthesis of a novel macrocyclic host molecule that forms in a single step from commercially available starting materials. The core of the macrocycle backbone possesses two quinone rings and, thus, is redox-active. Host-guest binding involving the clip-shaped cavity indicates selective binding of pyridine N-oxides based of the electron density of and steric bulk of the anionic oxygen.</div>

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Enantioselective Recognition of Chiral Guests by the Water-Soluble Chiral Keplerate {Mo132} Spherical Capsule with 30 Inner Lactate Ligands

10.26434/chemrxiv.8847923.v1 ◽

2019 ◽

Author(s):

Nancy Watfa ◽

Weimin Xuan ◽

Zoe Sinclair ◽

Robert Pow ◽

Yousef Abul-Haija ◽

...

Keyword(s):

Aqueous Solution ◽

Chiral Recognition ◽

Association Constants ◽

Water Soluble ◽

Enantioselective Recognition ◽

H Nmr ◽

Dosy Nmr ◽

Spherical Capsule ◽

Surface Pores ◽

Guest Chemistry

Investigations of chiral host guest chemistry are important to explore recognition in confined environments. Here, by synthesizing water-soluble chiral porous nanocapsule based on the inorganic metal-oxo Keplerate-type cluster, {Mo132} with chiral lactate ligands with the composition [Mo132O372(H2O)72(x-Lactate)30]42- (x = D or L), it was possible to study the interaction with a chiral guest, L/D-carnitine and (R/S)-2-butanol in aqueous solution. The enantioselective recognition was studied by quantitative 1H NMR and 1H DOSY NMR which highlighted that the chiral recognition is regulated by two distinct sites. Differences in the association constants (K) of L- and D-carnitine, which, due to their charge, are generally restricted from entering the interior of the host, are observed, indicating that their recognition predominantly occurs at the surface pores of the structure. Conversely, a larger difference in association constants (KS/KR = 3) is observed for recognition within the capsule interior of (R)- and (S)-2-butanol.

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