Host-guest complexation with various hydrophobic drugs has been used to enhance the solubility, permeability, and stability of guest drugs. Physical changes in hydrophobic drugs by complexation have been related to corresponding increases in the bioavailability of these drugs. Carbohydrates, including various derivatives of cyclodextrins, cyclosophoraoses, and some linear oligosaccharides, are ...

BACKGROUND This study aims to investigate the influence of different stirring time for synthesis of silver nanoparticles in glutathione (GSH) aqueous solution. The silver nanoparticles (Ag-NPs) were prepared by green synthesis method using GSH as reducing agent and stabilizer, under moderate temperature at different stirring times. Silver nitrate (AgNO3) was taken as the metal precursor while A...

Zn(II) sorption onto Al and Si oxides was studied as a function of pH (5.1-7.52), sorption density, and ionic strength. This study was carried out to determine the role of the various reaction conditions and sorbent phases in Zn complexation at oxide surfaces. Extended X-ray absorption fine structure (EXAFS) spectroscopy was used to probe the Zn atomic environment at the metal oxide/aqueous int...

Raman spectra of the cyclic hexapeptide cyclo-(L-prolylglycyl)3 and its Na+, K+, and Ca2+ complexes are reported for the solid state and for samples in solution. Model compounds and N-deuteration were used to aid mode identification. Spectra of the uncomplexed ionophore in solution are consistent with previously proposed solution conformations and permit the identification of spectral lines cha...

Using a co-complexation methodology the unsolvated lithium zincate [LiZn(HMDS)Me2] ( 4, HMDS = 1,1,1,3,3,3-hexamethyldisilazide) was prepared by reaction of an equimolar amount of LiHMDS with Me2Zn in a non-polar toluene-hexane solvent mixture. X-Ray crystallographic studies reveal that the asymmetric unit of 4 has a dinuclear arrangement, based on a planar LiNZnC four-membered ring. As a resul...

The aza-Diels-Alder cycloaddition of 1,2,4-triazines with alkynes offers a rapid and convenient method for the synthesis of highly substituted pyridines, but often requires harsh conditions and long reaction times. The present study offers a solution to these limitations by use of a temporary tether established by a Lewis acid-base complexation of in situ generated alkynylboranes and triazines ...

Donor-acceptor [2]catenanes based on cyclobis(paraquat-p-phenylene) as the pi-acceptor ring have been used prominently in the construction of functional molecular devices. We report here their thermodynamically controlled synthesis from isolated pi-donor and pi-acceptor rings under the catalytic influence of tetra butylammonium iodide. The initial nucleophilic attack of iodide ion, which opens ...

The title salt, Na(+)·C(6)H(13)O(9)S(-)·H(2)O, crystallizes with three independent cations, molecular anions and solvent water molecules in the asymmetric unit. This crystalline monohydrate addition product, formed by reaction of d-glucose and sodium hydrogen sulfite in water, forms a three-dimensional network through complex cation coordination and extensive inter-molecular hydrogen bonding. E...

Simple, rapid and sensitive spectrophotometric methods were developed for the determination of chlorodiazepoxide drugs in pharmaceutical dosage forms. This method is based on ion pair and charge transfer complexation reactions. The method is based on the reaction of the chlorodiazepoxide drug with Mo(V)–thiocyanate in hydrochloric acid medium followed by an extraction of the coloured ion-pair w...

5-Fluoro-2'-deoxyuridylate causes a rapid inactivation of thymidylate synthetase that is dependent upon prior complexation of the cofactor 5,10-methylenetetrahydrofolate. The enzyme-5-fluoro-2'-deoxyuridylate complex may be isolated on nitrocellulose membranes and is not disrupted by 6 M urea. Upon reaction of 5-fluoro-2'-deoxyuridylate with the enzyme in the presence of 5,10-methylenetetrahydr...