A novel method for the rapid preparation of starch esters is described herein, by rapid heating using microwave or conventional means. A 5-min method to prepare starch maleates with degree of substitution (DS) up to 0.25 was developed when microwave or conventional source assisted fast heating of starch in dimethyl sulfoxide (DMSO) reacted with 0.5 equiv. maleic anhydride in the presence of 0.5...

Asparaginase from Esckerickio coli B has been modified with increasing amounts of [r4C]succinic anhydride. Enzyme activity is enhanced when 15 % and 25 % of the lysyl residues are succinylated. Up to 40% of the lysyl residues were succinylated without destroying enzyme activity and without causing dissociation of this oligomeric protein. More extensive succinylation causes dissociation into sub...

Successive modification of starch with octenyl succinic anhydride (OSA) and plant-derived geraniol allows for a largely bio-derived derivative that can undergo facile reaction elemental sulfur to generate sustainable composite materials.

Non-covalent binding of avidin to biotinylated erythrocytes results in complement-dependent haemolysis. Biotinylated erythrocytes, as well as native cells, are not lysed by complement. Complement activation requires a tight contact between avidin and the erythrocyte membrane, since avidin does not in itself activate complement and does not inhibit lysis of sensitized sheep erythrocytes. The-eff...

The chemical modification of wood can be directed to improve various properties, e.g., the dimensional stability, hardness and/or durability against weathering. In this study, a Romanian softwood species Abies alba Mill. was treated and chemically modified using two cyclic acid anhydrides, i.e., maleic succinic, its interfacial properties relative unmodified wood. Structural changes, with focus...

ABSTRACT An efficient and economically viable approach for the large-scale conversion of artemisinin into the antimalarial frontline drug artesunate was developed. This advanced synthesis includes an NaBH4-induced reduction, followed by an esterification with succinic anhydride under basic conditions. The entire conversion follows the principles of green chemistry, i.e., application of reusable...

Esterified kraft lignins (KL) were prepared by reaction with maleic anhydride (MA), succinic anhydride (SA), and phthalic anhydride (PA) in acetone solutions. The esterified lignins were characterized using ATRFTIR, solid state CP-MAS 13C NMR spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). PA modification resulted in the highest weight gain percent (...

In this work was synthesized an amino-steroid derivative (4); the route involved preparation of dihydrotestosterone-hemisuccinate (2) by the esterification of dihydrotestosterone (1) using succinic anhydride and pyridine (method A) or using succinic acid and 1,3 dicyclohexylcarbodiimide in presence of p-toluensulfonic acid (method B). After 2 was coupled to 4-hidroxy benzoic acid using 1,3 dicy...