Universal abt compounds and uses thereof

A compound of one of formulae II-a, II-b, II-c, II-d, II-e or II-f:

• of a pharmaceutically acceptable salt thereof, wherein:
• each of R1, R3 and R5 is independently hydrogen or an optionally substituted group selected from C1-6 aliphatic, a 3-8 membered saturated or partially unsaturated monocyclic carbocyclic ring, phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring, a 4-8 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen oxygen, of sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• or:
• R1 and R1′ are optionally taken together with their intervening carbon atom to form a 3-8 membered saturated or partially unsaturated spirocyclic carbocyclic ring or a 4-8 membered saturated or partially unsaturated spirocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• R3 and R3′ are optionally taken together with their intervening carbon atom to form a 3-8 membered saturated or partially unsaturated spirocyclic carbocyclic ring or a 4-8 membered saturated or partially unsaturated spirocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• an R5 group and the R5′ group attached to the same carbon atom are optionally taken together with their intervening carbon atom to form a 3-8 membered saturated or partially unsaturated spirocyclic carbocyclic ring or a 4-8 membered saturated or partially unsaturated spirocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen oxygen, or sulfur;
• or
• two R5 groups are optionally taken together with their intervening atoms to form a C1-10 bivalent straight or branched saturated or unsaturated hydrocarbon chain wherein 1-3 methylene units of the chain are independently and optionally replaced with —S—, —SS—, —N(R)—, —O—C(O)—, —OC(O)—, —C(O)O—, —C(O)N(R)—, —N(R)C(O)—, —S(O)—, —S(O)2—, or -Cy1-, wherein each -Cy1- is independently a 5-6 membered heteroarylenyl with 1-4 heteroatoms independently selected from nitrogen oxygen or sulfur;
• each of R1′, R3′ and R5′ is independently hydrogen or C1-3 aliphatic;
• each of R2, R4 and R6 is independently hydrogen, or C1-4 aliphatic, or:
• R2 and R1 are optionally taken together with their intervening atoms to form a 4-8 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen or sulfur,
• R4 and R3 are optionally taken together with their intervening atoms to form a 4-8 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• or
• an R6 group and its adjacent R5 group are optionally taken together with their intervening atoms to form a 4-8 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• and
• L1 is a trivalent linker moiety.

A compound having the structure of formula I-b:

• or a pharmaceutically acceptable salt thereof, wherein:
• each Xaa is independently an amino acid residue;
• each z is independently 1-50;
• each L is independently a linker moiety;
• TBT is a target binding moiety,
• each Rc is independently -La-R′;
• each of a1 and a2 is independently 0-200, wherein at least one of a1 and a2 is not 0;
• b is 1-200;
• each La is independently a covalent bond, or an optionally substituted bivalent group selected C1-C20 aliphatic or C1-C20 heteroaliphatic having 1-5 heteroatoms, wherein one or more methylene units of the group are optionally and independently replaced with —C(R′)2—, -Cy-, —O—, —S—, —S—S—, —N(R′)—, —C(O)—, —C(S)—, —C(NR′)—, —C(O)N(R′)—, —N(R′)C(O)N(R′)—, —N(R′)C(O)O—, —S(O)—, —S(O)2—, —S(O)2N(R′)—, —C(O)S— or —C(O)O—;
• each -Cy- is independently an optionally substituted bivalent group selected from a C3-20 cycloaliphatic ring, a C6-20 aryl ring, a 5-20 membered heteroaryl ring having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon, and a 3-20 membered heterocyclyl ring having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon;
• each R′ is independently —R, —C(O)R, —CO2R, or —SO2R;
• each R is independently —H, or an optionally substituted group selected from C1-30 aliphatic, C1-30 heteroaliphatic having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon, C6-30 aryl, C6-30 arylaliphatic, C6-30 arylheteroaliphatic having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon, 5-30 membered heteroaryl having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon, and 3-30 membered heterocyclyl having 1-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon, or
• two R groups are optionally and independently taken together to form a covalent bond, or:
• two or more R groups on the same atom are optionally and independently taken together with the atom to form an optionally substituted, 3-30 membered, monocyclic, bicyclic or polycyclic ring having, in addition to the atom, 0-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon;
• or
• two or more R groups on two or more atoms are optionally and independently taken together with their intervening atoms to form an optionally substituted, 3-30 membered, monocyclic, bicyclic or polycyclic ring having, in addition to the intervening atoms, 0-10 heteroatoms independently selected from oxygen, nitrogen, sulfur, phosphorus and silicon.