Probing Inclusion Complexes of Pentoxifylline and Pralidoxim inside Cyclic Oligosaccharides by Physicochemical Methodologies

2019 ◽  
Vol 233 (8) ◽  
pp. 1109-1127
Author(s):  
Biraj Kumar Barman ◽  
Kanak Roy ◽  
Mahendra Nath Roy
Keyword(s):  
Surface Tension ◽  
Free Energy ◽  
Inclusion Complexes ◽  
Apparent Molar Volume ◽  
Nmr Spectra ◽  
Drug Delivery Systems ◽  
Surface Tension Data ◽  
H Nmr ◽  
Ft Ir ◽  
Inclusion Phenomena

Abstract Structurally different Molecules namely Pentoxifylline and Pralidoxim were chosen along with α-cyclodextrin and β-cyclodextrin to study host-guest inclusion phenomena. The formations of host guest inclusion complexes were confirmed by studying 1H-NMR spectra, FT-IR spectra, apparent molar volume and viscosity co-efficient. The stabilities of inclusion complexes were compared calculating the binding constant from UV-VIS spectroscopic study. The 1:1 stoichiometry of the inclusion complexes were also determined by analysing the Jobs plot and surface tension data. The values for Gibbs’ free energy were found negative for both the processes. Based on all the above experiments the inclusion processes were found feasible for both the compounds. These types of inclusion complexes are of high interest in the field of research and industry as these are used as drug delivery systems.

Study on Host-Guest Inclusion Complexation of a Drug in Cucurbit [6]uril

2018 ◽  
Vol 232 (2) ◽  
pp. 281-293 ◽  
Author(s):  
Kanak Roy ◽  
Subhadeep Saha ◽  
Biswajit Datta ◽  
Lovely Sarkar ◽  
Mahendra Nath Roy
Keyword(s):  
Surface Tension ◽  
Specific Conductivity ◽  
Inclusion Complexation ◽  
Conductivity Measurements ◽  
Saline Environment ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
The Stability ◽  
Ft Ir Spectroscopy

AbstractAssembly of pyridine-2-aldoxime drug with cucurbit [6]uril (CB[6]) has been investigated by1H-NMR and 2D-ROESY NMR, UV-Vis spectroscopy, FT-IR spectroscopy, surface tension and conductivity measurements in aqueous saline environment. The distinct cationic receptor feature and the cavity dimension of the CB[6] emphasize that the macro-cyclic host molecule remain as complex with the nerve stimulus drug molecule. The results obtained from surface tension and specific conductivity measurements suggest 1:1 inclusion complex formation between drug and CB[6]. The stability constant evaluated by UV-Vis spectroscopic approach is 2.21×105M−1at 298.15 K, which indicates that the complex is sufficiently stable at physiological temperature.

Thermo-mechanical and surface properties of POSS reinforced structurally different diamine cured epoxy nanocomposites

RSC Advances ◽  
2014 ◽  
Vol 4 (85) ◽  
pp. 45433-45441 ◽  
Author(s):  
K. Sethuraman ◽  
P. Prabunathan ◽  
M. Alagar
Keyword(s):  
Bisphenol A ◽  
Surface Properties ◽  
Nmr Spectra ◽  
Epoxy Nanocomposites ◽  
H Nmr ◽  
Ft Ir ◽  
C Nmr

In the present study three structurally different diamines namely bisphenol-A based ether diamine, octane diol based ether diamine, and capron based diamine were synthesized and characterized using FT-IR, 1H-NMR and 13C-NMR spectra.

scholarly journals Preparation and Characterization of Styrene Bearing Diethanolamine Side Group, Styrene Copolymer Systems, and Their Metal Complexes

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Aslışah Açıkses ◽  
Necmittin Çömez ◽  
Fatih Biryan
Keyword(s):  
Free Radical ◽  
Electrical Properties ◽  
Metal Complexes ◽  
Nmr Spectra ◽  
Side Group ◽  
Conductivity Measurements ◽  
H Nmr ◽  
Ft Ir ◽  
Polymerization Method

The two copolymer systems of styrene bearing diethanol amine side group and styrene were prepared by free radical polymerization method at 60°C in presence of 1,4-dioxane as solvent and AIBN as initiator. Their metal complexes were prepared by reaction of the copolymer used as ligand P(DEAMSt-co-St)L′′ and Ni(II) and Co(II) metal ions, which was carried out in presence of ethanol and NaOH at 65°C for 48 h in pH = 7.5. The structures of the copolymers used as ligand and metal complexes were identified by FT-IR, 1H-NMR spectra, and elemental analysis. The properties of the copolymers used as ligand and metal complexes were characterized by SEM-EDX, AAS, DSC, TGA, and DTA techniques. Then, the electrical properties of the copolymers and metal complexes were examined as a function of the temperature and frequency, and the activation energies (Ea) were estimated with conductivity measurements.

Modeling of the Thermodynamic Properties of Liquid Fe-Ni and Fe-Co Alloys From the Surface Tension Data

2011 ◽  
Vol 56 (1) ◽  
pp. 13-23 ◽  
Author(s):  
W. Gąsior ◽  
P. Fima ◽  
Z. Moser
Keyword(s):  
Surface Tension ◽  
Free Energy ◽  
Surface Layer ◽  
Thermodynamic Properties ◽  
Gibbs Free Energy ◽  
Thermodynamic Data ◽  
Excess Gibbs Free Energy ◽  
Surface Tension Data ◽  
Co Alloys ◽  
Good Agreement

Modeling of the Thermodynamic Properties of Liquid Fe-Ni and Fe-Co Alloys From the Surface Tension DataRecently proposed method of modeling of thermodynamic properties of liquid binary alloys from their surface tension data is described. The method utilizes Melford and Hoar equation, relating surface tension with excess Gibbs free energy, combined with new description of the monatomic surface layer and β parameter. The method is tested on Fe-Ni and Fe-Co alloys and the obtained results show very good agreement with experimental thermodynamic data of other authors. The model allows also to calculate the surface tension from thermodynamic data, and it gives better agreement with experimental results than those modeled with the use of Butler equation and traditionally defined monatomic surface layer and β = 0.83.

Synthesis and Property of Liquid Crystal Polymers Containing Photosensitive Groups

2011 ◽  
Vol 181-182 ◽  
pp. 131-134
Author(s):  
Ji Lei Li ◽  
Wei Min Zhang ◽  
Yu Lei Zhao ◽  
Jia Ling Pu
Keyword(s):  
Thermal Properties ◽  
Liquid Crystal ◽  
Nematic Phase ◽  
Nmr Spectra ◽  
Liquid Crystalline ◽  
Liquid Crystal Polymers ◽  
Crystal Temperature ◽  
Mesogenic Group ◽  
H Nmr ◽  
Ft Ir

The synthesis and free-radical polymerization of the acrylates monomer containing photosensitive chalcone group and the acrylates monomer containing mesogenic group are described in this paper. The monomers and polymers were characterized by FT-IR and 1 H NMR spectra. The thermal properties of polymers were measured by DSC and the liquid crystalline texture was measured by POM. And the results indicated that the polymers showed typical nematic phase and liquid crystal temperature range was 74 °C-103 °C.

scholarly journals SYNTHESIS OF SURFACTANS DILAUROYL MALTOSE THROUGH ACETILATION REACTION OF MALTOSE FOLLOWED BY TRANSESTERIFICATION REACTION WITH METHYL LAURATE

2010 ◽  
Vol 9 (3) ◽  
pp. 445-451
Author(s):  
Daniel Tarigan
Keyword(s):  
Surface Tension ◽  
Nmr Spectroscopy ◽  
Acetic Anhydride ◽  
Column Chromatography ◽  
Transesterification Reaction ◽  
Methyl Laurate ◽  
H Nmr ◽  
Ft Ir

Maltose has been partially acetylated from the reaction of melted maltose and acetic anhydride without solvent and catalyst to produce maltocyl acetate with the yield of 67%. Lauryc acid can be methanolized using H2SO4 as the catalyst to produce methyl laurate with the yield of 92%. The transesterification of methyl laurate and maltocyl acetate in methanol using sodium methoxyde as the catalyst at reflux, yielded a novel compound dilauroyl maltose after isolated by column chromatography, with the yield of 59%. Methyl laurate, maltocyl acetate, and dilauroyl maltose were confirmed by FT-IR and 'H-NMR spectroscopy, and the surface tension of dilauroyl maltose solution  was determined by Du-Nuoy tensiometer to obtain the HLB value of 2.67.   Keywords: Surfactant Transesterification, Maltose

scholarly journals Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Mohammad Reza Poor Heravi ◽  
Marjan Ashori
Keyword(s):  
Boric Acid ◽  
Nmr Spectra ◽  
Aqueous Media ◽  
Reaction Conditions ◽  
Efficient Catalyst ◽  
H Nmr ◽  
Convenient Synthesis ◽  
Ft Ir ◽  
Acid Catalyzed ◽  
C Nmr

Synthesis of benzimidazoles has been developed by theo-phenylenediamine with aldehydes using boric acid an efficient catalyst under mild reaction conditions in aqueous media. The product is applicable to aryl and heteroaryl aldehydes. This reaction led to the formation of benzimidazoles new derivatives in good yields. The FT-IR,19F-NMR,1H-NMR,13C-NMR spectra and elemental analysis confirm the structure of compounds.

scholarly journals Synthesis, Characterization and Antibacterial Activity of Schiff Bases and their Metal Complexes Derived from 4-Acyl-1-phenyl-3-methyl-2-pyrazolin-5-ones and 2-Amino-4(4'-methylphenyl)-thiazole

2010 ◽  
Vol 7 (4) ◽  
pp. 1396-1406 ◽  
Author(s):  
A. S. Thakar ◽  
K. K. Singh ◽  
K. T. Joshi ◽  
A. M. Pancholi ◽  
K. S. Pandya
Keyword(s):  
Antibacterial Activity ◽  
Schiff Bases ◽  
Elemental Analysis ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Electrical Conductance ◽  
H Nmr ◽  
Infrared Spectral ◽  
Ft Ir ◽  
C Nmr

4-Acyl-1-phenyl-3-methyl-2-pyrazolin-5-ones condensed with 2-amino-4(4'-methylphenyl)-thiazole to form Schiff base. These Schiff bases from complexes of type ML22H2O (M=Mn, Fe, Co, Ni and Cu). Elemental analysis, magnetic susceptibility, electrical conductance, electronic and Infrared spectral data suggested octahedral structure for the complexes. All the compounds were tested for their antibacterial activity. The result indicates that the growth of the tested organism was inhibited by most of the compounds. These Schiff bases are characterized by elemental analysis, mass spectra,1H-NMR spectra,13C NMR spectra and FT IR spectra.

Synthesis of 5-Benzoylacenaphthene in the Presence of [Bmim] Cl/AlCl3 Ionic Liquid

2012 ◽  
Vol 443-444 ◽  
pp. 830-836
Author(s):  
Shu Yun Zhu ◽  
De Li Jiang ◽  
Yu Fang ◽  
Ji Min Xie ◽  
Min Chen
Keyword(s):  
Ionic Liquid ◽  
Catalytic Activity ◽  
Nmr Spectra ◽  
Benzoyl Chloride ◽  
Environmentally Friendly ◽  
H Nmr ◽  
Product Separation ◽  
Ft Ir

Acylation of acenaphthene with benzoyl chloride to 5-benzoylacenaphthene catalyzed by [Bmin]Cl/AlCl3 ([Bmin]+ = 1-butyl-3-methylimidazolium cation) ionic liquid was investigated. Pure 5-benzoylacenaphthene was obtained and the structure of 5-benzoylacenaphthene was identified by GC/MS, FT-IR and 1H NMR spectra. The yield of 5-benzoylacenaphthene was up to 85.2 % and the selectivity towards 5-benzoylacenaphthene was up to 89.6 %. The [Bmim]C1/A1C13 ionic liquid catalyst shows well catalytic activity after running for 5 times. The facile product separation and the recycling performance of the ionic liquid catalyst is expected to contribute to the development of clean and environmentally friendly strategy for the synthesis of 5-benzoylacenaphthene.

Synthesis and Dynamic NMR Study of Fluorinated Dialkyl 2-[(tert-butylimino)-methylene]-3-[(2-alkoxy-2-oxoacetyl)-2-fluoroanilino]-succinates

2005 ◽  
Vol 2005 (8) ◽  
pp. 537-539 ◽  
Author(s):  
Issa Yavari ◽  
Farough Nasiri ◽  
Hoorieh Djahaniani ◽  
Hamid R. Bijanzadeh
Keyword(s):  
Free Energy ◽  
Nmr Spectra ◽  
Dynamic Nmr ◽  
Single Bond ◽  
Aryl Group ◽  
Restricted Rotation ◽  
H Nmr ◽  
Dialkyl Acetylenedicarboxylates ◽  
Free Energy Of Activation ◽  
Nmr Study

The 1:1 adduct produced in the reaction between tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped by alkyl 2-fluoro-anilino-2-oxo-acetates or ethyl 2-oxo-2-(trifluoromethylanilino)-acetate to produce functionalised ketenimines in good yields. Dynamic NMR effects were observed in the 1H NMR spectra of these compounds as a result of restricted rotation around the single bond linking the aryl group to the ketenimine system. The free energy of activation (ΔG≠) for this process is 64.9–66.5 kJ mol−1.

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