The present article describes novel oxidative protocols for direct esterification of alcohols. The protocols involve successful demonstrations of both "cross" and "self" esterification of a wide variety of alcohols. The cross-esterification proceeds under a simple transition-metal-free condition, containing catalytic amounts of TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy)/TBAB (tetra-n-butylamm...

We studied cholesterol synthesis from [14C]acetate, cholesterol esterification from [14C]oleate, and cellular cholesterol and cholesteryl ester levels after incubating cells with apoE-free high density lipoproteins (HDL) or low density lipoproteins (LDL). LDL suppressed synthesis by up to 60%, stimulated esterification by up to 280%, and increased cell cholesteryl ester content about 4-fold. Es...

The rate of degradation of oxidatively modified low density lipoprotein (Ox-LDL) by human endothelial cells was similar to that of unmodified low density lipoprotein (LDL), and was approximately 2-fold greater than the rate of degradation of acetylated LDL (Ac-LDL). While LDL and Ac-LDL both stimulated cholesterol esterification in endothelial cells, Ox-LDL inhibited cholesterol esterification ...

The esterification of bagasse with glutaric anhydride could increase surface adhesion compatibility and the surface of derived polymers has the potential of immobilizing peptides or proteins for biomedical application. Due to its complicated components, the esterification mechanism of bagasse esterified with glutaric anhydride in ionic liquids has not been studied. In this paper, the homogenous...

The esterification activity of microbial lipase (triacyl glycerol hydrolase, E.C. 3.1.1.3) in water-organic biphasic solvent system has been investigated. The lipase produced from Rhizopus arrhizus NCM997 strain by solid-state fermentation, using rice bran as substrate, exhibited novel capability of catalyzing esterification reaction. The partially purified lipase was coated with nonionic surfa...

BACKGROUND Enzymatic biodiesel production by transesterification in solvent media has been investigated intensively, but glycerol, as a by-product, could block the immobilized enzyme and excess n-hexane, as a solution aid, would reduce the productivity of the enzyme. Esterification, a solvent-free and no-glycerol-release system for biodiesel production, has been developed, and two-step catalysi...

a most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. in this process an azeotroping agent, toluene, was used to facilitate continuous removal of water by dis...

In this study, waste shrimp shells from industry were used as a heterogeneous bio-based catalyst for trans-esterification reaction of fresh palm oil. CaO was prepared calcination. Surface area, phase composition, and basicity the calcined shell catalysts studied using N2 adsorption (BET), X-ray diffraction (XRD), CO2 temperature-programmed-desorption (CO2-TPD), respectively. The influence calci...

Book: M. P. Doyle, M. A. McKervey, T. Ye Modern Catalytic Methods for Organic Synthesis with Diazo Compounds: From Cyclopropanes to Ylides; Wiley-VCH: New York, 1998. Comment: The authors propose an intriguing mechanistic pathways to explain the selectivity in the cyclopropanation with diazo reagents bearing two carboxy groups. It is proposed that the chiral rhodium complex preferentially binds...

Objectives: The objective of this study was to analyze the fatty acid content, antioxidant, and antibacterial activities of hydro-methanolic extract of Adonis wolgensis L. (A. wolgensis L.) growing wild in north of Iran. Materials and Methods: Oils of A. wolgensis L. was obtained by means of Soxhlet apparatus from leaves and stems. Methyl esters were derived from the oily mixtures by trans-este...