Bicyclic peptide ligands and uses thereof

A compound of formula I:

• or a pharmaceutically acceptable salt thereof, wherein:
• each of L1, L2, and L3 is independently a covalent bond or a C1-8 bivalent hydrocarbon chain wherein one, two or three methylene units of the chain are optionally and independently replaced by —S—, —N(R)—,—O—,—C(O)—,—OC(O)—, —C(O)O—, —C(O)N(R)—, —N(R)C(O)—,—S(O)—,—S(O)2— or —N(R)CH2C(O)—;
• each R is independently hydrogen or C1-4 alkyl;
• Scaffold is selected from the group consisting of
• Loop A
• and Loop B is
• or
• Loop A is
• and Loop B is
• indicates the site of attachment to the N-terminus of the Bicycle;
• indicates the site of attachment to the C-terminus of the Bicycle;
• Peptide1 is hydrogen, or a natural or unnatural amino acid wherein the acid is connected to the N-terminus of the Bicycle via an amide bond;
• Peptide2 is —OH, —NH2, or a natural or unnatural amino acid wherein the amino group is connected to the C-terminus of the Bicycle via an amide bond;
• each of R1 and R2 is independently
• each of R4 is independently hydrogen, C1-4 aliphatic, and
• each of n is independently 0 or 1, and
• wherein a value of n=0 for R′ results in a terminal amine, —NH2, and a value of n=0 for R2 results in a terminal carboxamide, —C(O)NH2.