甲胺基-三聚乙二醇-羧酸

反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Under an inert atmosphere of argon, in a round bottom flask, with magnetic stirring, 120.1 mg of 3-[2-(2-{2-[2-(2,2,2-trifluoro-acetylamino)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-propionic acid methyl ester, 1 ml of anhydrous THF and 59.8 μl of CH3I and successively introduced. The reaction medium is cooled with a ice/water bath at about 0° C., and 16.1 mg of NaH (50% pure in oil) is slowly added by small portions. After 15 min at 0° C., and 1 hr at RT, the crude reaction medium is concentrated to dryness under RP, and diluted with 0.5 ml of THF and 0.8 ml of water. At RT, 30.6 mg of LiOH is then added to the reaction medium. The crude reaction medium is kept 2 hrs at RT, 16 hrs at −20° C., and then purified by flash-chromatography on 30 g of C18-grafted silica gel (gradient of elution water:acetonitrile from 95:5 to 5:95 by volume). After concentration of fractions containing the desired product under RP, 115.3 mg of 3-(2-{2-[2-(2-methylamino-ethoxy)-ethoxy]-ethoxy}-ethoxy)-propionic acid are obtained in the form of a yellow oil. 1 hr at RT, the crude reaction medium is concentrated to dryness under RP diluted with 0.5 ml of THF and 0.8 ml of water At RT, 30.6 mg of LiOH is then added to the reaction medium The crude reaction medium is kept 2 hrs at RT, 16 hrs at −20° C. purified by flash-chromatography on 30 g of C18-grafted silica gel (gradient of elution water:acetonitrile from 95:5 to 5:95 by volume) After concentration of fractions containing the desired product under RP, 115.3 mg of 3-(2-{2-[2-(2-methylamino-ethoxy)-ethoxy]-ethoxy}-ethoxy)-propionic acid are obtained in the form of a yellow oil