a general, mild and efficient protocol has been developed for the synthesis of esters and thioesters. the process has been taking place using tetra n-butylammonium iodide (tbai) as a phase-transfer catalyst and in the presence of potassium carbonate (k2co3). a wide range of esters and thioesters was prepared in high yields and suitable times by the treatment of alcohols, phenols and thiols with...

To a dried extract Containing hippuric acid (HA), 1.0 mL of acetic anhydride and 2.0 mL of 0.5% p-dlmethyiamlnobenzaldehyde (DAB) solution In pyridine were added, and the solution was kept at 40 O C for 1 h after thorough mlxing. The absorbance was then determlned at 458 nm agalnst a blank containing acetic anhydride, DAB, and pyridine. This method was in good agreement with Beer’s law within 1...

Insulin receptors from human placenta have been labeled by using an oxidative iodination procedure (iodogen-mediated or chloramine-T-mediated), Bolton-Hunter reagent or [3H]acetic anhydride. The oxidative iodination procedure reduces the affinity for 131I-insulin and the receptor protein becomes fragmented into smaller pieces with an s20,w value of 5-6. However, treatment with Bolton-Hunter rea...

The aim of this study was to investigate the effect of esterification via acetic or propionic anhydride on the surface roughness of eastern cottonwood. Eastern cottonwood (Populous deltoides) was esterified by using acetic or propionic anhydride without using any solvent or catalyst under different conditions. Two different weight percentage gains (WPGs) were obtained for each of the modifying ...

Azalactone 1 can be synthesized via treatment of 4chlorobenzoyl glycine with p-anisaldehyde in the presence of acetic anhydride and sod Acetate. The behaviour of azalactone 1 towards nitrogen nucleophiles, for example, anthranilic acid, 6-aminopyrimidin-2,4-dione and 2-amino-6-phenyl 1,3,4thiadiazole can be investigated. Benzoxazone 2 can be treated with hydrazine hydrate, hydroxylamine hydroch...

The structure of antibiotic A33853, isolated from the culture broth of Streptomyces sp., NRRL 12068, is reported. The structure was deduced from an X-ray crystallographic study of its tetraacetyl derivative. Tetraacetyl A33853 is unique because it contains an anhydride moiety, an unexpected product from the reaction of A33853 with acetic anhydride and pyridine.

The effect of chemical modification on a D(+)-galactose-specific lectin isolated from winged-bean tubers was investigated to identify the type of amino acid involved in its haemagglutinating activity. Various anhydrides of dicarboxylic acids, such as acetic anhydride, succinic anhydride, maleic anhydride and citraconic anhydride, modified 57-68% of the amino groups of the winged-bean tuber lect...

Photochemically inactive diarylethene derivatives having a N-(O-hydroxyphenyl) group underwent photochromic reaction when they were esterified by the addition of acetic anhydride.

0144-8617/$ see front matter Published by Elsevier doi:10.1016/j.carbpol.2009.11.048 q Names are necessary to report factually on availa neither guarantees nor warrants the standards of the name USDA implies no approval of the products to the also be suitable. * Corresponding authors. Tel.: +1 504 286 4450; Cheng), tel.: +1 309 681 6406 (A. Biswas). E-mail addresses: [email protected] (H.N....