Catalytic synthesis of chloroacetates with thermoregulated ionic liquids based on vanadium-substituted polyoxometalate.

A series of polyoxometalate-based ionic liquid (POM-IL) catalysts with functional sulfonic acid groups, [TEAPS] PW V O ( = 1, 2, 3) were synthesized and characterized by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectrophotometry (FT-IR), UV-Vis spectrophotometry (UV), potentiometric titration and thermogravimetry-differential scanning calorimetry (TG-DSC). The catalytic ability and reusability of the POM-IL catalysts were evaluated on esterification of chloroacetic acid and -amyl alcohol. The optimum reaction conditions, 0.

Preparative Separation of Phenylethanoid and Secoiridoid Glycosides from Ligustri Lucidi Fructus by High-Speed Counter-Current Chromatography Coupled with Ultrahigh Pressure Extraction.

Three phenylethanoid glycosides, echinacoside (), salidroside (), and acteoside (), and three secoiridoid glycosides, isonuezhenide (), nuezhenoside G13 (), and specnuezhenide (), have been extracted and separated by a combined method of ultrahigh pressure extraction (UPE) and high-speed counter-current chromatography (HSCCC) from Ligustri Lucidi Fructus. For the UPE, the optimal extraction was developed with conditions including solvent of 90% ethanol, sample to solvent ratio of 1:20 g/mL, pressure of 200 MPa, and time of 2 min, which rendered the yields of compounds and were 15.0 and 78.

Synthesis and conductive performance of polyoxometalate acid salt gel electrolytes.

Two vanadium-substituted polyoxometalate acid salt gel electrolytes, [PyPS]HSiWVO and [PyPS]HSiWVO have been synthesized using a 1-(3-sulfonic group) propylpyridine (PyPS) and a Keggin vanadium-substituted heteropoly acid HSiWVO through an ionic self-assembly method, and adjusting the ratio of cation and anion. A substitution effect of the acid salt gel electrolytes has been investigated. Interestingly, when protons of the polyoxometalate acid salt gel electrolytes are substituted, both the conductivity and the phase transformation temperature increase.

Potential advantages of a novel chitosan-N-acetylcysteine surface modified nanostructured lipid carrier on the performance of ophthalmic delivery of curcumin.

The transient precorneal retention time and low penetration capacity into intraocular tissues are the key obstacles that hinder the ophthalmic drug delivery of many therapeutic compounds, especially for drugs with poor solubility and permeability. To break the stalemate, N-acetyl-L-cysteine functionalized chitosan copolymer (CS-NAC), which exhibit marked bioadhesion and permeation enhancing effect, was synthesized. The curcumin encapsulated NLC (CUR-NLC) was produced and optimized followed by surface absorption of CS-NAC.

Effect of particle size on oral absorption of carvedilol nanosuspensions: in vitro and in vivo evaluation.

The purpose of this work was to explore the particle size reduction effect of carvedilol on dissolution and absorption. Three suspensions containing different sized particles were prepared by antisolvent precipitation method or in combination with an ultrasonication process. The suspensions were characterized for particle size, surface morphology, and crystalline state.