ORTHOESTER DERIVATIVES OF CROWN ETHERS AS CARRIERS FOR PHARMACEUTICAL AND DIAGNOSTIC COMPOSITIONS

摘要

This invention relates to A crown ether of formula (I) wherein m is 4, 5, 6, 7, or 8 and i is, independently for each occurrence, 1 or 2; at least one occurrence in the crown ether of R1, R2 and the carbon to which R1 and R2 are attached, said carbon being bound directly to an ether oxygen of formula (I), form together a group of formula (II) wherein L is a linker which is absent or selected from a covalent bond and (CR5R6)n, useful as carriers for pharmaceutical and diagnostic compositions.