Folate conjugates of albumin-binding entities

Compounds of formula I,

• wherein
• Z is a pteroate or derivative thereof,
• L1,L4 are independently of each other a covalent bond or a straight-chain or branched C(1-8)alkyl, which is unsubstituted or substituted by at least one CN, Hal, OR′, NHR′, CO2R′ or NO2, wherein R′ represents H or C(1-8)alkyl,
• L2 is a covalent bond or a linking group, such as straight-chain or branched C(1-8)alkyl, which is unsubstituted or substituted by at least one OR′, NHR′, or CO2R′, and wherein one or more of the non-adjacent CH2 groups may independently be replaced by a group selected from —O—, —CO—, —CO—O—, —O—CO—, —NR′—, —NR′—CO—, —CO—NR′, wherein R′ represents H or C(1-8)alkyl,
• L3 is a covalent bond or a linking group, such as straight-chain or branched C(1-8)alkyl, which is unsubstituted or substituted by at least one CN, Hal, OR′, NHR′, CO2R′ or NO2, and wherein one or more of the non-adjacent CH2 groups may independently be replaced by a group selected from —O—, —CO—, —CO—O—, —O—CO—, —NR′—, —NR′—CO—, —CO—NR′—, —NR′—CO—O—, —O—CO—NR′—, —NR′—CO—NR′—, —CH═CH—, —C≡C—, —O—CO—O—, —S—R′—, —SO3R′—, and a five-membered azaheterocycle, wherein R′ represents H or C(1-8)alkyl,
• Y1,Y3 are independently of each other O, N or S,
• A1, A2, A3 are independently of each other H, a capping group, or an albumin binder,
• M is a radionuclide-based therapeutic or diagnostic moiety,
• m1, m2 are independently of each other 0, 1, 2 or 3,
• with the proviso that at least one, preferably one, of A1, A2 and A3 is an albumin binder.