Patent ID: 8026285

Claim:
An oligomer or pharmaceutically acceptable salt thereof of formula I or II: [R 1 —O—(Y) b —C(O)CH 2 —(X) a —OC(O)] w —R I [R 2 —C(O)O—(X 1 ) a —CH 2 C(O)—(Y 1 ) b —O] w —R II wherein: R 1 —O— is a biologically active compound residue; R 2 —C(═O)O— is a biologically active compound residue; X is selected from: —OC(═O)CH 2 — (inverse glycolic acid moiety), —OC(═O)CH(CH 3 )— (inverse lactic acid moiety), —OC(═O)CH 2 OCH 2 CH 2 — (inverse dioxanone acid moiety), —OC(═O)CH 2 CH 2 CH 2 CH 2 CH 2 — (inverse caprolactone acid moiety), —OC(═O)(CH 2 ) y —, or —OC(═O)CH 2 (OCH 2 CH 2 ) z —; X 1 is selected from: —CH 2 C(═O)O— (glycolic acid moiety), —CH(CH 3 )C(═O)O— (lactic acid moiety), —CH 2 CH 2 OCH 2 C(═O)O— (dioxanone acid moiety), —CH 2 CH 2 CH 2 CH 2 CH 2 C(═O)O— (caprolactone acid moiety), —(CH 2 ) y C(═O)O—, or —(CH 2 CH 2 O) n CH 2 C(═O)O—; Y is selected from: —C(═O)CH 2 O— (glycolic ester moiety), —C(═O)CH(CH 3 )O— (lactic ester moiety), —C(═O)CH 2 OCH 2 CH 2 O— (dioxanone ester moiety), —C(═O)CH 2 CH 2 CH 2 CH 2 CH 2 O— (caprolactone ester moiety), —C(═O)(CH 2 ) m O—, or —C(═O)CH 2 —O—(CH 2 CH 2 O) n —; Y 1 is selected from: —OCH 2 C(═O)— (inverse glycolic ester moiety), —OCH(CH 3 )C(═O)— (inverse lactic ester moiety), —OCH 2 CH 2 OCH 2 C(═O)— (inverse dioxanone ester moiety), —OCH 2 CH 2 CH 2 CH 2 CH 2 C(═O)— (inverse caprolactone ester moiety), —O(CH 2 ) m C(═O)—, or —O(CH 2 CH 2 O) n OCH 2 C(═O)—; R is a di-, tri, tetra-, penta- or hexaradical derived from C 2-25 alkyl, aryl, or aryl-(C 1-6 alkyl) 1-3 -, wherein from 1-3 of the CH 2 groups within the alkyl chain are optionally independently replaced by O atoms, such that each of said O atom is attached only to carbon atoms in the alkyl chain, with the proviso that multiple O atoms that replace CH 2 groups within the alkyl chain must be separated from each other by at least two carbon atoms and from the di-, tri, tetra-, penta- or hexaradical chain ends by at least one carbon atom; or R is the backbone of a polymer or copolymer bearing carboxylic acid and/or hydroxyl functional groups, where the average molecular weight of the polymer or copolymer is between 500 to 5000 and wherein w is an integer from about 6 to about 50; each a and b is independently an integer from about 1 to about 10; each m, n, y, and z is independently an integer from about 2 to about 24; and w is an integer from about 2 to about 6.