Polyoxazolines with inert terminating groups, polyoxazolines prepared from protected initiating groups and related compounds

A polyoxazoline-phospholipid conjugate comprising a lipid portion linked to a polyoxazoline portion having the structure:

• -LI-{POZI-POZII}a-S-LII-R* or I-{POZI-POZII}a-S-LII-;
• wherein
• POZI is a polyoxazoline polymer of the structure —[N(CO—R′—Z)CH2CH2]m;
• POZII is a polyoxazoline polymer of the structure [N(COR2)CH2CH2]n;
• R′, LI, and LII are each optional linking groups;
• Z is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;
• R2 is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;
• R* is an unsubstituted or substituted alkyl, alkenyl, aralkyl, heterocycylalkyl group or an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;
• I′ is a group present at the initiator position;
• n is an integer from 0-1000, provided that when n=0, then m is >1;
• m is an integer 1-1000;
• and
• a is ran, which indicates a random copolymer, or block, which indicates a block copolymer.