Hybrid block copolymer micelles with mixed stereochemistry for encapsulation of hydrophobic agents

A multiblock copolymer of formula I:

• wherein:
• n is 10-2500;
• m is 0 to 1000;
• m′ is 2 to 1000;
• Rx is a natural or unnatural amino acid side-chain group that is capable of crosslinking;
• Ry forms a hydrophobic D,L-mixed poly(amino acid) block;
• R1 is -Z(CH2CH2Y)p(CH2)tR3, wherein:
• Z is —O—, —S—, —C≡C—, or —CH2—;
• each Y is independently —O— or —S—;
• p is 0-10;
• t is 0-10;
• and
• R3 is hydrogen, —N3, —CN, a mono-protected amine, a di-protected amine, a protected aldehyde, a protected hydroxyl, a protected carboxylic acid, a protected thiol, a 9-30 membered crown ether, or an optionally substituted group selected from aliphatic, a 5-8 membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, an 8-10 membered saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a detectable moiety;
• Q is a valence bond or a bivalent, saturated or unsaturated, straight or branched C1-12 hydrocarbon chain, wherein 0-6 methylene units of Q are independently replaced by -Cy-, —O—, —NH—, —S—, —OC(O)—, —C(O)O—, —C(O)—, —SO—, —SO2—, —NHSO2—, —SO2NH—, —NHC(O)—, —C(O)NH—, —OC(O)NH—, or —NHC(O)O—, wherein:
• -Cy- is an optionally substituted 5-8 membered bivalent, saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• R2a is a mono-protected amine, a di-protected amine, —N(R4)2, —NR4C(O)R4, —NR4C(O)N(R4)2, —NR4C(O)OR4, or —NR4SO2R4;
• and
• each R4 is independently hydrogen or an optionally substituted group selected from aliphatic, a 5-8 membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, an 8-10 membered saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a detectable moiety, or:
• two R4 on the same nitrogen atom are taken together with said nitrogen atom to form an optionally substituted 4-7 membered saturated, partially unsaturated, or aryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.