Patent ID: 11944689
Assignee: SEAGEN INC.
Field: Pharmaceuticals (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 17:
18. The Ligand Drug Conjugate compound of claim 1 wherein the compound is represented by the structure of Formula 1a or Formula 2a:, or pharmaceutically acceptable salt(s) thereof, wherein
R19B is —CH(CH3)—CH(OH)-Ph, —CH(CO2H)—CH(OH)—CH3, or —CH(CO2H)—CH2Ph;, or
wherein the compound is represented by the structure of Formula 1b or Formula 2b:, or pharmaceutically acceptable salt(s) thereof, wherein
R2A is C(═O)CH3, —CH2CH3, —CH2CH═CH2 or —CH2C(═CH2)CH3;
subscript u is 0 or 1; and

R7B is —OH when subscript u is 1 or is absent when subscript u is 0
wherein in Formula 1a, Formula 2a, Formula 1b and Formula 2b,
S is a sulfur atom of the Ligand Unit, wherein that sulfur atom in Formula 2a is bonded the carbon α or β to the carboxylic acid functional group of the indicated succinic acid amide (M3) moiety,
Ra3 is —H, optionally substituted C1-C6 alkyl or optionally substituted —C1-C4 alkylene-(C6-C10 aryl), wherein the basic nitrogen atom bonded to Ra3 is optionally protonated;
LP is a Parallel Connector Unit;
PEG is a PEG Unit;
subscript v is an integer ranging from 1 to 4;
each RE and RF is independently selected from the group consisting of —H, optionally substituted C1-C6 alkyl, optionally substituted C2-C6 alkylene, optionally substituted C6-C10 arylene or optionally substituted C5-C10 heteroarylene,
or RE and RF together with the carbon atom to which both are attached defines an optionally substituted spiro C3-C6 carbocyclo, or RE and RF from adjacent carbon atoms together with these atoms and any intervening carbon atoms defines an optionally substituted C5-C6 carbocyclo with any remaining RE and RF as previously defined,
XLP is provided by a natural or un-natural amino acid side chain or is selected from the group consisting of −0-, —NRLP—, —S—, —S(═O)—, —S(═O)2—, —C(═O)—, —C(═O)N(RLP)—, —N(RLP)C(═O)N(RLP)—, and —N(RLP)C(═NRLP)N(RLP)—, or C3-C8 heterocyclo;
wherein each RLP is independently selected from the group consisting of hydrogen and optionally substituted C1-C6 alkyl, or two of RLP together along with the carbons atoms to which they are attached and their intervening atoms define a C5-C6 heterocyclo and any remaining RLP are as previously defined.