Hydration of Complexes of Some Univalent Cations with Polyethylene Glycol Ligands in Nitrobenzene Saturated with Water

1992 ◽  
Vol 57 (2) ◽  
pp. 289-295 ◽  
Author(s):  
Emanuel Makrlík
Keyword(s):  
Polyethylene Glycol ◽  
Hydration Numbers ◽  
Univalent Cations ◽  
Peg 400

The hydration numbers of the complexes ML+ formed by some univalent cations (M+ = Li+, Na+, NH4+, K+, Rb+ and Cs+) and polyethylene glycol ligands (L = PEG 200, PEG 300 and PEG 400) in nitrobenzene saturated with water were determined. The highest differences between the hydration numbers of the cations M+ and the complexes ML+ were found in the systems with the Na+ cation.

Extraction of strontium and barium by nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1982 ◽  
Vol 47 (5) ◽  
pp. 1444-1464 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík ◽  
Jiří Rais ◽  
Miroslav Kyrš
Keyword(s):  
Polyethylene Glycol ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Hydration Numbers ◽  
Nitrobenzene Solution ◽  
Karl Fischer Titration ◽  
Peg 400 ◽  
Extraction Constants

Extraction of microamounts of Sr2+ and Ba2+ from 0.2-1.0M-HClO4 by the nitrobenzene solutions of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (PEG) (Mr = 200, 300, 400) has been investigated. It has been found that the extraction of the protonized polyethylene glycol molecule (H+ + L ##e HL+, where the bar denotes species present in the organic phase) and the extraction of the complex between the extracted ion and polyethylene glycol, i.e., M2+ +L + 2 H+ ##e ML2+ + 2 H+, are the predominant reactions in this system. The respective equilibrium constants have been determined. The hydration numbers of HL+ and ML2+ ions in the organic phase have been obtained from the determination of water content by Karl Fischer titration method. The extraction constants and stability constants in the organic phase increase in the sequence H+ < Sr2+ < Ba2+ and PEG 200 < PEG 300 < PEG 400, while the hydration numbers decrease in the same sequence. Correlations between the hydration numbers and the extraction constants for these cations have been found.

A Simple Approach to the One-Pot Three Component Synthesis of 4Hpyrimido [2,1-b] benzothiazole Derivatives Using Polyethylene Glycol (PEG-400)

2015 ◽  
Vol 12 (3) ◽  
pp. 197-204 ◽  
Author(s):  
Prabhakar Rairala ◽  
Bandi Yadagiri ◽  
Rajashaker Bantu ◽  
Vijayacharan Guguloth ◽  
Lingaiah Nagarapu
Keyword(s):  
Polyethylene Glycol ◽  
Simple Approach ◽  
One Pot ◽  
Benzothiazole Derivatives ◽  
Peg 400 ◽  
The One

Extraction of polyethylene glycols with dicarbolide solutions in nitrobenzene

1990 ◽  
Vol 55 (8) ◽  
pp. 1959-1967 ◽  
Author(s):  
Petr Vaňura ◽  
Pavel Selucký
Keyword(s):  
Polyethylene Glycol ◽  
Molecular Mass ◽  
Extraction Constant ◽  
Metal Extraction ◽  
Polyethylene Glycols ◽  
Relative Molecular Mass ◽  
Published Data ◽  
Average Molecular Mass ◽  
Peg 400 ◽  
Extraction Constants

The extraction of polyethylene glycol of average molecular mass 400 (PEG 400) with dicarbolide solution in nitrobenzene and of longer-chain polyethylene glycol, of average molecular mass 1 500 (PEG 1 500), with chlorinated dicarbolide solution in nitrobenzene was studied. During the extraction of PEG 400, the polyethylene glycol solvates the Horg+ ion in the organic phase giving rise to the HLorg+ species (L is polyethylene glycol). The obtained value of the extraction constant Kex(HLorg+) = 933 is consistent with published data of metal extraction. Extraction of PEG 1 500 was treated applying the simplified assumption that the thermodynamic behaviour of PEG 1 500 is the same as that of n molecules of polyethylene glycol with relative molecular mass 1 500/n, each solvating one cation. For this model, the value of n = 3.2 ± 1.1 and the values of the extraction constants of the HL1/n,org+ and HL2/n,org+ species were obtained by using the adapted program LETAGROP. This value of n is consistent with published extraction data in the presence of polyethylene glycol with a relative molecular mass from 200 to 1 000.

ChemInform Abstract: Polyethylene Glycol (PEG-400): A Mild and Efficient Reaction Medium for One-Pot Synthesis of 3-Hydroxy-3-(pyridin-2-ylmethyl)indolin-2-ones.

ChemInform ◽  
2013 ◽  
Vol 44 (42) ◽  
pp. no-no
Author(s):  
M. Raghu ◽  
M. Rajasekhar ◽  
B. Chandra Obula Reddy ◽  
C. Suresh Reddy ◽  
B. V. Subba Reddy
Keyword(s):  
Polyethylene Glycol ◽  
Reaction Medium ◽  
One Pot ◽  
Peg 400 ◽  
One Pot Synthesis

Facile Polyethylene Glycol (PEG-400) Promoted Synthesis of Some New Heteryl (E)-styryl Sulfones

2009 ◽  
Vol 2009 (4) ◽  
pp. 237-239 ◽  
Author(s):  
Nalajam Guravaiah ◽  
Vedula Rajeswar Rao
Keyword(s):  
Polyethylene Glycol ◽  
Room Temperature ◽  
Reaction Medium ◽  
Peg 400 ◽  
Convenient Synthesis

An efficient and convenient synthesis of heteryl ( E)-styryl sulfones is described. Reaction of an 3-(2-bromoacetyl)coumarin with sodium ( E)-styrenesulfinates yields the corresponding styryl sulfones promoted by polyethylene glycol (PEG-400) as an efficient reaction medium at room temperature

scholarly journals FORMULATION AND EVALUATION OF ATORVASTATIN CALCIUM NANOCRYSTALS CONTAINING P-GLYCOPROTEIN INHIBITORS FOR ENHANCING ORAL DELIVERY

2021 ◽  
pp. 19-23
Author(s):  
SARAH LABIB ◽  
MOHAMED NASR ◽  
MOHAMED NASR
Keyword(s):  
Polyethylene Glycol ◽  
Oral Drug Delivery ◽  
Tween 80 ◽  
Degree Of Crystallinity ◽  
Oral Drug ◽  
Tween 20 ◽  
Atorvastatin Calcium ◽  
Peg 400 ◽  
P Glycoprotein ◽  
Saturated Solubility

Objective: The main objective of this study was to develop atorvastatin calcium (ATR) as an oral drug delivery system for a P-glycoprotein (P-gp) substrate drug using different pharmaceutical excipients that inhibit P-glycoprotein and evaluate the influence of nanocrystals on the dissolution characteristics and bioavailability compared to the plain drug. Methods: A nanosuspension was prepared by Solvent-antisolvent precipitation method using a solvent containing stabilizer that act as a p-gp inhibitor dissolved in distilled water as polyethylene glycol 300, polyethylene glycol 400 (PEG 300, PEG 400), tween 20 and tween 80 while the solvent selected for atorvastatin calcium was methanol. The concentrations were as follows: PEG 300 and 400 = 0.25% w/v, tween 20 and 80 = 0.75% v/v. Nanocrystals were extracted from the suspension and characterized. Results: Particle size of the drug was 1307±127.79 nm while the formulas prepared ranged from 223±17.67 to 887±58.12 nm. Pure ATR had a saturated solubility of 0.059±0.005 mg/ml and the prepared nanocrystals ranged from 0.32±0.021 to 0.88±0.019 mg/ml. The Percentage of drug released of plain atorvastatin calcium reached 41.49% while the formula ranged from 44.32 to 61.5%. Both XRD and SEM discussed the degree of crystallinity as follows: F1<F2<F4<F3<ATR. Conclusion: 0.3% of PEG 300 and PEG 400 were not enough to formulate proper nanocrystals while 0.75% tween 20 and tween 80 achieved acceptable formulas. F4 which is prepared with tween 80 exhibited the highest enhancement in saturated solubility, dissolution rate and subsequently expected to have improved oral bioavailability.

Polyethylene glycol (PEG-400): a mild and efficient reaction medium for one-pot synthesis of 3-hydroxy-3-(pyridin-2-ylmethyl)indolin-2-ones

2013 ◽  
Vol 54 (27) ◽  
pp. 3503-3506 ◽  
Author(s):  
M. Raghu ◽  
M. Rajasekhar ◽  
B. Chandra Obula Reddy ◽  
C. Suresh Reddy ◽  
B.V. Subba Reddy
Keyword(s):  
Polyethylene Glycol ◽  
Reaction Medium ◽  
One Pot ◽  
Peg 400 ◽  
One Pot Synthesis
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