| 主权项 |
1. A compound of Formula (II):or a salt thereof, wherein:
each A1 is independently selected from a thiol-reactive group, an amine-reactive group, an avidin-binding group, a photoreactive group, an alkyne-reactive group, and an azide-reactive group; each X1 and X3 is independently selected from a covalent bond, C1-20 alkanediyl, substituted C1-20 alkanediyl, C1-20 heteroalkanediyl, substituted C1-20 heteroalkanediyl, C3-12 cycloalkanediyl, substituted C3-12 cycloalkanediyl, C3-12 heterocycloalkanediyl, substituted C3-12 heterocycloalkanediyl, C4-20 alkanecycloalkanediyl, substituted C4-20 alkanecycloalkanediyl, C4-20 heteroalkanecycloalkanediyl, substituted C4-20 heteroalkanecycloalkanediyl, C6-20 arenediyl, substituted C6-20 arenediyl, C6-20 heteroarenediyl, substituted C6-20 heteroarenediyl, C7-20 alkanearenediyl, substituted C7-20 alkanearenediyl, C6-20 heteroalkanearenediyl, substituted C6-20 heteroalkanearenediyl, and —(CH2)n1—(CH2—CH2—O)n2—(CH2)n3—, wherein:
each n1 and n3 is independently an integer selected from 0 to 5; andeach n2 is independently an integer selected from 1 to 25; each X2 is independently selected from a covalent bond, —O—, —S—, —N—, —N═, —N═N—, —N═C—, —SO—, —SO2—, —SO2N—, —SS—, —C(O)—, —C(O)O—, —C(O)N—, —C(O)S—, —C(O)N—N═, —OP(O)(OH)O—, —OC(O)O—, —OC(O)N—, —NC(O)N—, and —NC(S)N; each R1 and R2 is independently selected from hydrogen, C1-6 alkyl, substituted C1-6 alkyl, C1-6 heteroalkyl, substituted C1-6 heteroalkyl, C6-10 aryl, substituted C6-10 aryl, C6-10 heteroaryl, and substituted C6-10 heteroaryl; D is selected from a therapeutic agent having at least one primary amine group, a therapeutic agent having at least one secondary amine group, a therapeutic agent having at least one hydroxy group, and a therapeutic agent having at least one thiol group; and n5 is an integer selected from 1 to 20. |
