scholarly journals Supramolecular Encapsulation of Vitamin B6by Macrocyclic Nanocontainer Cucurbit[7]uril

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Wanying Li ◽  
Shengke Li ◽  
Ian W. Wyman ◽  
Donal H. Macartney ◽  
Qingwen Zhang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Molecular Modeling ◽  
Vitamin B ◽  
Pyridoxine Hydrochloride ◽  
Biologically Relevant ◽  
H Nmr ◽  
Molecular Container ◽  
Uv Visible ◽  
The Stability ◽  
First Time

A pharmaceutically and biologically relevant molecule, pyridoxine hydrochloride (vitamin B6), was encapsulated inside the cavity of a molecular container, cucurbit[7]uril (CB[7]), in aqueous solution. The CB[7] based “nanocapsule” of vitamin B6has been investigated for the first time, via1H NMR and UV-visible spectroscopic titrations (including Job’s plot) andab initiomolecular modeling. The results have demonstrated that vitamin B6forms stable host-guest complexes within CB[7] in 1 : 1 stoichiometry, with a binding affinity of(4.0±0.5)×103 M−1. Such a nanocapsule could potentially find application in vitamin B6formulation for the purpose of enhancing the stability, absorption, and delivery of this important vitamin.

Synthesis and properties of a sterically encumbered poly(thienylene vinylene): poly[E-1,2-(4,4prime-dihexyl-2,2prime-dithienyl)ethylene]

1998 ◽  
Vol 76 (11) ◽  
pp. 1524-1529
Author(s):  
Jimmy Lowe ◽  
Carl Bartels ◽  
Steven Holdcroft
Keyword(s):  
Ftir Spectroscopy ◽  
Electrically Conducting ◽  
H Nmr ◽  
Visible Photoluminescence ◽  
Micron Size ◽  
Visible Irradiation ◽  
Uv Visible ◽  
The Stability ◽  
Doped Polymer ◽  
Polythiophene Derivative

Electrically conducting poly[E-1,2-(4,4prime-dihexyl-2,2prime-dithienyl)ethylene] was synthesized and structurally characterized by UV-visible, 1H NMR, and FTIR spectroscopy. The head-to-head arrangement of the alkylthiophene dyads directly affects the UV-visible, photoluminescence, and electroluminescence maxima of the polymer. The conductivity of the doped polymer was measured to be ~2 S cm-1 and the stability of the oxidized polymer possessing various dopants was compared. UV-visible irradiation of PDHDTE rendered the films insoluble and photolithography was used to produce micron-size images. FTIR was used to monitor the photoproducts during photolysis of PDHDTE. Mechanisms of photooxidation were proposed, based on the photoproducts observed.Key words: polythiophene derivative, head-to-head dyad, photolithography, photooxidation, electroluminescence.

scholarly journals Amphiphilic Fluorescent Well-Defined Living Polymer from Indole-3-Carboxaldehyde and 4-Bromo-1, 8-Naphthalic Anhydride: Synthesis and Characterization

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Ambika Srivastava ◽  
Pooja Singh ◽  
Arti Srivastava ◽  
Rajesh Kumar
Keyword(s):  
Aqueous Solution ◽  
Fluorescence Emission ◽  
Green Fluorescence ◽  
Blue Fluorescence ◽  
Naphthalic Anhydride ◽  
H Nmr ◽  
Uv Visible ◽  
Polymer Bearing ◽  
Absorption And Emission Spectroscopy ◽  
Good Agreement

We reported a well-defined amphiphilic fluorescent polymer bearing indole repeating units with naphthalimide pendants obtained by ATRP followed by chemical modification. The obtained polymer poly (N-allyl indole-2-(4-hydroxybutyl)-1, 8-naphthalimide) (PAIHN) was characterized by 1H NMR, FTIR, and GPC. The polymer showed a specific fluorescence emission maximum at 538 nm excited at 435 nm in aqueous solution. The amphiphilic nature of the polymer was investigated in aqueous solution using two spectroscopic methods, namely, absorption and emission spectroscopy. The Critical Miceller Concentration values obtained by UV-visible and fluorescence are in good agreement with each other. The micelles were characterized by TEM at concentration of 0.014 mg/mL. The polymer PAIHN prepared after tweaking exhibits green fluorescence at 538 nm due to the significant effect of naphthalimide moieties, whereas before tweaking the polymer poly (1-allyl indole-3-carbaldehyde) (PAIC) exhibits blue fluorescence at 425 nm due to indole repeating units of the polymer.

Exploring inclusion complexes of cyclodextrins with quinolinone based gastro protective drug for enhancing bioavailability and sustained dischargement

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Niloy Roy ◽  
Beauty Mahato ◽  
Debadrita Roy ◽  
Koyeli Das ◽  
Mahendra Nath Roy
Keyword(s):  
Controlled Release ◽  
Inclusion Complexes ◽  
Inclusion Complexation ◽  
The Body ◽  
H Nmr ◽  
Prolonged Effect ◽  
Solvent Systems ◽  
Uv Visible ◽  
The Stability ◽  
2D Roesy

AbstractSolid rebamipide based inclusion complexes were achieved by freeze-dry method and characterized by FTIR, UV–visible, 1H-NMR, 2D-ROESY, fluorescence spectroscopy, SEM and conductance. The enzyme substituted emission spectrum of the two comparative inclusion complexes with β-cyclodextrin (β-CD) and HP-β-CD in the diverse solvent systems determined the controlled release of the drug were the mid of interest. Amylase increased the stability of the inclusion complexation, proved that if it is taken together with the inclusion complex, the effectiveness and impact of the inclusion complexes will have a prolonged effect in the body. It could significantly improve the bioavailability of rebamipide.

scholarly journals Host-Guest Complexations of Amine Boranes and Isoelectronic/Isostructural Quaternary Alkylammonium Cations by Cucurbit[7]uril in Aqueous Solution

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Mona A. Gamal-Eldin ◽  
Donal H. Macartney
Keyword(s):  
Aqueous Solution ◽  
Hydrophobic Effect ◽  
Host Molecule ◽  
Guest Complex ◽  
H Nmr ◽  
Hydrophobic Cavity ◽  
Host Guest Complex ◽  
Dipole Interactions ◽  
The Stability ◽  
Amine Boranes

The host-guest complexation of six amine boranes (R3NBH3) by the macrocyclic host molecule cucurbit[7]uril (CB[7]) in aqueous solution has been investigated using 1H and 11B NMR spectroscopy. The limiting complexation-induced 1H and 11B chemical shift changes indicate that the amine boranes are included in the hydrophobic cavity of the host molecule. The host-guest stability constants for neutral  R3NBH3∙CB[7]  complexes (in the range of 105-107M-1) have been determined by 1H NMR competition experiments and are compared with the corresponding values for the isoelectronic/isostructural  R3NCH3∙CB[7] + complexes. Ammonia borane (H3NBH3) does not form a host-guest complex with CB[7]. The trends in the host-guest stability constant with the guest molar volume are examined, and the stability is ascribed to the hydrophobic effect (packing coefficient) and quadrupole-dipole interactions.

Synthesis of Novel Oxazolidines and Study of Its Naked Eye CO2 Detecting Properties

2020 ◽  
Vol 20 (10) ◽  
pp. 6428-6434
Author(s):  
Rangaraju Satish Kumar ◽  
Heon Seung Lee ◽  
Jiwon Ryu ◽  
Young-A Son
Keyword(s):  
Ethanol Solution ◽  
Visible Absorption Spectrum ◽  
Visible Absorption ◽  
H Nmr ◽  
Naked Eye ◽  
Nmr Techniques ◽  
Uv Visible ◽  
The Stability ◽  
Repeatability Test ◽  
C Nmr

Herewith, we synthesized the new oxazolidines (SP-1, SP-2 and SP-3) by without using any withdrawing or donating substitution, and for these molecules we demonstrated CO2 sensing properties in naked eye condition with different colors (yellow and magenta). All the dyes showed different colors in the presence and absence of CO2 in ethanol solution with the concept of ring closing and opening. In UV-visible absorption spectrum all the compounds showed visible light absorptions after purging of CO2. To confirm this mechanism for SP-1 molecule case, we approached the 1H-NMR and 13C-NMR techniques deuterated methanol as a solvent and we clearly identified. The stability of the SP-1 molecule in ethanol for CO2 purging case, we studied repeatability test up to ten cycles and we confirmed that there is no any decrease in sensing ability.

The features of cerium coordination chemistry in the complexes with tetra-15-crown-5-phthalocyanine

2006 ◽  
Vol 10 (07) ◽  
pp. 931-936 ◽  
Author(s):  
Kirill P. Birin ◽  
Yuliya G. Gorbunova ◽  
Aslan Yu. Tsivadze
Keyword(s):  
Direct Interaction ◽  
Lanthanide Ions ◽  
H Nmr ◽  
Double Decker ◽  
Composition And Structure ◽  
Cerium Ion ◽  
Sandwich Type ◽  
The Stability ◽  
First Time

For the first time, using a method of direct interaction of crownphthalocyanine and cerium(III) acetate in the presence of strong organic base, a sandwich-type double-decker cerium(IV) bis[tetra-(15-crown-5)-phthalocyaninate] [ Ce 4+( R 4 Pc 2−)2]0 ( R 4 Pc 2− = [4,5,4',5',4″,5″,4‴,5‴-tetrakis-(1,4,7,10,13-pentaoxapentadecamethylene)-phthalocyaninate-anion]) is synthesized with 60% yield. The composition and structure of the obtained complex are confirmed using spectral methods. UV-vis, IR and 1 H NMR spectroscopy and MALDI-TOF mass-spectrometry were used for characterization of the complex. It has been shown, that a particular feature of cerium ion in the complex with tetra-15-crown-5-phthalocyanine is the stability of oxidation state +4, unlike other lanthanide ions. The Ce(IV) complex has been obtained despite using a Ce(III) salt in synthesis. It has been found that the introduction of crown ether substituents in the phthalocyanine molecule results in a decreased stability of the compound to oxidation in comparison with unsubstituted and tert-butylsubstituted cerium phthalocyaninates.

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

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, {Mo<sub>132</sub>} with chiral lactate ligands with the composition [Mo<sub>132</sub>O<sub>372</sub>(H<sub>2</sub>O)<sub>72</sub>(<i>x-</i>Lactate)<sub>30</sub>]<sup>42-</sup> (<i>x</i> = D or L), it was possible to study the interaction with a chiral guest, L/D-carnitine and (<i>R</i>/<i>S</i>)-2-butanol in aqueous solution. The enantioselective recognition was studied by quantitative <sup>1</sup>H NMR and <sup>1</sup>H 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 (K<i><sub>S</sub></i>/K<i><sub>R</sub></i> = 3) is observed for recognition within the capsule interior of (<i>R</i>)- and (<i>S</i>)-2-butanol.

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