Patent ID: 7368260

Claim:
A method of synthesizing an insulin polypeptide-oligomer conjugate comprising: contacting a proinsulin polypeptide comprising an insulin polypeptide coupled to one or more peptides by peptide bond(s) capable of being cleaved to yield the insulin polypeptide with an oligomer comprising the structure of Formula II: A-X(CH 2 ) m Y(C 2 H 4 O) n R (II) wherein: A is —C(O)—OH, C(S)—OH, —C(S)—SH, —OH, —SH, or NH 2 ; X is an oxygen atom or a covalent bond, with the proviso that X is not an oxygen atom when A is —OH; Y is an ester, an ether, a carbamate, a carbonate, or an amide bonding moiety; m is between 1 and 30; n is between 1 and 50; and R is an alkyl moiety, a sugar moiety, cholesterol, adamantane, an alcohol moiety, or a fatty acid moiety; under conditions sufficient to couple the oligomer to the insulin polypeptide portion of the proinsulin polypeptide and provide a proinsulin polypeptide-oligomer conjugate; and cleaving the one or more peptides from the proinsulin polypeptide-oligomer conjugate to provide the insulin polypeptide-oligomer conjugate.