Patent ID: 6020373
Filing Date: 2000-02-01
Classification: C07C,C07D

Abstract:
A derivative of methoxypolyethylene glycol, comprising one or more methoxypolyethylene glycols terminated in amide or amine linkages to ethylenediamine, diethylenetriamine, or polyethyleneimines, in which remaining nitrogen bonds are covalently linked to the alpha carbon of acetic acid residues, the carboxylate groups being in the form of a free acid, an ion with a pharmacologically acceptable counter-ion, or an alkyl ester, wherein the derivative has the following formula (I) ##STR7## wherein one of R.sub.1 and R.sub.2 is formula (III) and the other is selected from formulas (II) and (III): ##STR8## and one R.sub.3 is formula (IV) and each of the remaining R.sub.3 is independently selected from formula (IV) ##STR9## or from the group consisting of --CH.sub.2 COOH; --CH.sub.2 COO.sup.- Na.sup.+ ; --CH.sub.2 COO.sup.- Ca.sup.++ /2; --CH.sub.2 COOCH.sub.3 ; --CH.sub.2 COOC.sub.2 H.sub.5 ; and --CH.sub.2 COOC.sub.3 H.sub.7 ;wherein a is 0 to 6; each b is independently 0 to 18; each c is independently 6 to 10; and d is 0 to 1.