5(6)-carboxy-rhodamine 110 isomers were rapidly synthesized by condensation of 3-aminophenol and trimellitic anhydride using microwave irradiation as heating method. after esterification of the two isomers, separation and hydrolyzation provided target products,5-carboxy-rhodamine 110 and 6-carboxy-rhodamine 110, in high yields. the results shows microwave irradiation can effectively reduce the ...

In this study, the kinetics for reaction of tert-butanol esterification with acetic acid in presence Dowex 50Wx8 catalyst was investigated. The kinetic experiments were conducted 1000 milliliter vessel at temperatures ranged from 50 - 80 oC, loading 25-50 g/L, and molar ratios to 1/3 – 3/1. rate found increase increasing temperature loading. It also conversion increases as ratio alcohol Non-ide...

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...

BACKGROUND Natural polysaccharides such as starch are becoming increasingly interesting as renewable starting materials for the synthesis of biodegradable polymers using chemical or enzymatic methods. Given the complexity of polysaccharides, the analysis of reaction products is challenging. RESULTS Esterification of starch with fatty acids has traditionally been monitored by saponification an...

Cytochrome P-450 (CYP) isoforms responsible for the cleavage of Hantzsch pyridine ester at the 3-position of pranidipine were studied in vitro using cDNA-expressed human CYP enzymes. CYP1A1, 1A2, 2D6, and 3A4 cleaved the ester with a catalytic activity of 5.5, 0. 93, 13.1, and 22.4 nmol/30 min/nmol P-450, respectively. CYP2A6, 2B6, 2C8, 2C9, 2C19, and 2E1 were not involved in the de-esterificat...

BACKGROUND Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic acids through esterification alters their solubility and enhances their use as food antioxidant additives as well...

A sulfonated polyethersulfone (SPES)/polyethersulfone (PES) blend catalytic membrane was prepared and used as a heterogeneous catalyst in the esterification of the acidified oil (acid value 153 mg KOH/g) with methanol for producing biodiesel. The results showed that the free fatty acids conversion reached 97.6% using SPES/PES catalytic membrane under the optimal esterification conditions. Meanw...

supercritical carbon dioxide (sc-co2) was used as solvent to synthesize oleyl oleate as an analog of jojoba oil from oleic acid and oleyl alcohol with high conversion (100%) of the acid into ester in a short time of 100 min. utilizing a low cost solid catalyst, p-toluenesulfonic acid monohydrate (ptsa), the esterification reaction was performed, without any prior preparation step, in a flow mod...

In this study, a solid acid was prepared by the sulfonation of surface modified α-zirconium phosphate (ZrP) single-layer nanosheets (SO3H@ZrP), and the prepared solid acid was investigated for the esterification of oleic acid with methanol to produce biodiesel. For comparison, liquid H2SO4 and commercial Amberlyst® 15 catalyst were also evaluated for the same reaction under the same conditions....