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N-Hydroxysuccinimide (NHS) is an organic compound with the formula (CH 2 CO) 2 NOH. It is a white solid that is used as a reagent for preparing active esters in peptide synthesis. It can be synthesized by heating succinic anhydride with hydroxylamine or hydroxylamine hydrochloride. [2]
Hantzsch ester refers to an organic compound with the formula HN(MeC=C(CO 2 Et)) 2 CH 2 where Me = methyl (CH 3) and Et = ethyl (C 2 H 5).It is a light yellow solid. The compound is a 1,4-dihydropyridine.
Nefkens and Tesser developed a technique for generating active esters from N-hydroxyphthalimide [14] for use in peptide synthesis, [15] an approach later extended to using N-hydroxysuccinimide. [16] The ester linkage is formed between the N -hydroxyphthalimide and a carboxylic acid by elimination of water, the coupling achieved with N , N ...
An example of an ester formation is the substitution reaction between a carboxylic acid (R−C(=O)−OH) and an alcohol (R'OH), forming an ester (R−C(=O)−O−R'), where R and R′ are organyl groups, or H in the case of esters of formic acid.
Water purification combines a number of methods to produce potable or drinking water. Downstream processing refers to purification of chemicals, pharmaceuticals and food ingredients produced by fermentation or synthesized by plant and animal tissues, for example antibiotics, citric acid, vitamin E, and insulin.
Active esters are often used in peptide synthesis, e.g., N-hydroxysuccinimide, hydroxybenzotriazole. [1] Active esters of acrylic acid are precursors to polymers with reactive side chains. [4] The concept of active esters extends to esters of phosphoric and sulfuric acids. One such case is dimethylsulfate, a strong methylating agent.
To ensure consistency and repeatability, the methods use in the chemical analysis of water samples are often agreed and published at a national or state level. By convention these are often referred to as "Blue book". [4] [5] Certain analyses are performed in-field (e.g. pH, specific conductance) while others involve sampling and laboratory ...
A synthesis of 1,4-dihydropyridines in aqueous micelles catalyzed by PTSA under ultrasonic irradiation. Using condensation of benzaldehyde , ethyl acetoacetate and ammonium acetate as a model, experiments have proven that when catalyzed by p-toluenesulfonic acid (PTSA) under ultrasonic irradiation, the reaction can have a product yield of 96% ...