Patent ID: 11931414
Assignee: SEAGEN INC.
Field: Pharmaceuticals (Chemistry)
Classification: CPC A  C | IPC A  C

Claim 3:
4. The Ligand Drug Conjugate compound of claim 1, wherein HN-DA has the structure of:, or a salt thereof, and HN+-DA has the structure of:, or a salt thereof, wherein
R4 is independently selected from the group consisting of hydrogen and optionally substituted C1-C4 alkyl; and
the pound sign (#) indicates the point of covalent attachment to LO;
the wavy line indicates the site of covalent attachment to IN, and
wherein the sp2 carbon atom proximal to the carbonyl carbon atom is the site (as indicated) of said formal optional cyclization to HN/HN+ through an introduced optionally substituted non-aromatic carbon atom or an optionally substituted aromatic heteroatom.