Tubulysins and protein-tubulysin conjugates

A compound having the following formula

• or a pharmaceutically acceptable salt thereof, wherein
• BA is a binding agent;
• L is a linker covalently bound to BA and to T;
• T is
• wherein
• R1 is C1-C10 alkyl;
• R3 is —C(O)C1-C5 alkyl, —C(O)N(H)C1-C10 alkyl, or —(C1-C10 alkylene)-NR3aR3b,
• wherein R3a and R3b are independently in each instance, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R4 and R5 are, independently in each instance, hydrogen or C1-C5 alkyl;
• R6 is —OH, —O—, —NHNH2, or —NHNH—;
• R7 is, independently in each instance, hydrogen, —OH, —O—, halogen, or —NR7aR7b,
• wherein R7a and R7b are independently in each instance, a bond, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, acyl, and amino acid residue, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R8 is, independently in each instance, hydrogen, deuterium, —NHR9, or halogen,
• wherein R9 is hydrogen, —C1-C5 alkyl, or —C(O)C1-C5 alkyl;
• and
• m is one or two;
• Q is —CH2— or —O— wherein
• when Q is —O—, then R2 is C1-C10 alkyl, C1-C10 alkylene, C1-C10 alkynyl, C1-C10 alkynylene, a regioisomeric C1-C10 triazolylene, —C1-C10 alkylene-(5-membered heteroaryl), a regioisomeric —C1-C10 alkylene-(5-membered heteroarylene), —C1-C3 alkylene-Q1-(CH2)naryl, —C1-C3 alkylene-Q1-(CH2)narylene, C1-C3 hydroxyalkyl, or C1-C10 alkylether;
• or
• when Q is —CH2—, then R2 is C5-C10 alkyl, C5-C10 alkylene, C1-C10 alkynyl, C1-C10 alkynylene, a regioisomeric C1-C10 triazolylene, —C1-C10 alkylene-(5-membered heteroaryl), a regioisomeric —C1-C10 alkylene-(5-membered heteroarylene), —C1-C3 alkylene-Q1-(CH2)naryl, —C1-C3 alkylene-Q1-(CH2)narylene, C1-C3 hydroxyalkyl, or C1-C10 alkylether;
• and
• Q1 is —CH2— or —O—;
• wherein said regioisomeric triazolylene is unsubstituted or substituted with alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl;
• wherein said heteroaryl or regioisomeric heteroarylene is unsubstituted or substituted with alkyl, aminoalkyl, -alkylene-NH—, hydroxylalkyl, -alkylene-O—, carboxyalkyl, -alkylene-COO—, benzyl, or phenyl;
• wherein said aryl is unsubstituted or substituted with nitro, amino, or —NH—;
• and
• wherein n is an integer from one to five;
• and
• k is an integer from one to thirty.

A compound having the structure of Formula I:

• or a pharmaceutically acceptable salt thereof, wherein
• R1 is C1-C10 alkyl;
• R3 is —C(O)C1-C5 alkyl, —C(O)N(H)C1-C10 alkyl, or —(C1-C10 alkylene)-NR3aR3b,
• wherein R3a and R3b are independently in each instance, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R4 and R5 are, independently in each instance, hydrogen or C1-C5 alkyl;
• R6 is —OH or —NHNH2;
• R7 is, independently in each instance, hydrogen, —OH, halogen, or —NR7aR7b,
• wherein R7a and R7b are independently in each instance, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, acyl, and amino acid residue, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R8 is, independently in each instance, hydrogen, deuterium, —NHR9, or halogen,
• wherein R9 is hydrogen, —C1-C5 alkyl, or —C(O)C1-C5 alkyl;
• and
• m is one or two;
• Q is —CH2— or —O— wherein
• when Q is —O—, then R2 is C1-C10 alkyl, C1-C10 alkynyl, —C1-C10 alkylene-(5-membered heteroaryl), —C1-C3 alkylene-Q1-(CH2)naryl, or C1-C3 hydroxyalkyl;
• or
• when Q is —CH2—, then R2 is C5-C10 alkyl, C1-C10 alkynyl, —C1-C10 alkylene-(5-membered heteroaryl), —C1-C3 alkylene-Q1-(CH2)naryl, or C1-C3 hydroxyalkyl;
• and
• Q1 is —CH2— or —O—;
• wherein said heteroaryl is unsubstituted or substituted with alkyl, aminoalkyl, hydroxylalkyl, carboxyalkyl, benzyl, or phenyl;
• wherein said aryl is unsubstituted or substituted with nitro or amino;
• and
• wherein n is an integer from one to five.

A linker-payload having the formula

• L-T
• or a pharmaceutically acceptable salt thereof, wherein
• L is a linker covalently bound to T;
• T is
• wherein
• R1 is C1-C10 alkyl;
• R3 is —C(O)C1-C5 alkyl, —C(O)N(H)C1-C10 alkyl, or —(C1-C10 alkylene)-NR3aR3b
• wherein R3a and R3b are independently in each instance, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R4 and R5 are, independently in each instance, hydrogen or C1-C5 alkyl;
• R6 is —OH, —O—, —NHNH2, or —NHNH—;
• R7 is, independently in each instance, hydrogen, —OH, —O—, halogen, or —NR7aR7b,
• wherein R7a and R7b are independently in each instance, a bond, hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, acyl, and amino acid residue, wherein alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl are optionally substituted;
• R8 is, independently in each instance, hydrogen, deuterium, —NHR9, or halogen,
• wherein R9 is hydrogen, —C1-C5 alkyl, or —C(O)C1-C5 alkyl;
• and
• m is one or two;
• Q is —CH2— or —O— wherein
• when Q is —O—, then R2 is C1-C10 alkyl, C1-C10 alkylene, C1-C10 alkynyl, C1-C10 alkynylene, a regioisomeric C1-C10 triazolylene, —C1-C10 alkylene-(5-membered heteroaryl), a regioisomeric —C1-C10 alkylene-(5-membered heteroarylene), —C1-C3 alkylene-Q1-(CH2)naryl, —C1-C3 alkylene-Q1-(CH2)narylene, C1-C3 hydroxyalkyl, or C1-C10 alkylether;
• or
• when Q is —CH2—, then R2 is C5-C1i alkyl, C5-C10 alkylene, C1-C10 alkynyl, C1-C10 alkynylene, a regioisomeric C1-C10 triazolylene, —C1-C10 alkylene-(5-membered heteroaryl), a regioisomeric —C1-C10 alkylene-(5-membered heteroarylene), —C1-C3 alkylene-Q1-(CH2)naryl, —C1-C3 alkylene-Q1-(CH2)narylene, C1-C3 hydroxyalkyl, or C1-C10 alkylether;
• and
• Q1 is —CH2— or —O—;
• wherein said regioisomeric triazolylene is unsubstituted or substituted with alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, and acyl;
• wherein said heteroaryl or regioisomeric heteroarylene is unsubstituted or substituted with alkyl, aminoalkyl, -alkylene-NH—, hydroxylalkyl, -alkylene-O—, carboxyalkyl, -alkylene-COO—, benzyl, or phenyl;
• wherein said aryl is unsubstituted or substituted with nitro, amino, or —NH—;
• and
• wherein n is an integer from one to five.