Monoalkanoyl fluoresceins prodn. - by reacting fluorescein and a higher alkanoyl halide in an aprotic solvent

摘要

Prepn. of compounds of formula (I): (where n is 8-16) comprises reacting a 10-18C alkanoyl halide with fluorescein at 15 degrees-30 degrees C under anhydrous conditions in an inert atmosphere in an aprotic organic solvent selected from DMF, DMSO or hexamethyl phosphoric triamide, the reaction mixt., after completion, is neutralised with a basic material and the product isolated by filtering on an adsorbing filter medium (alumina or silica gel) then eluted with an aromatic solvent-ether mixt. contg. 2-15 vol. of aromatic solventand1 vol. of ether, and crystallising (I) from hexane. (I) are useful in fluorometric methods for determining lipase activity of body fluids (I) are obtd. in sufficient purity and higher yields.