Compound having a structure represented by one or more of the formulas I-a1 and I-c1: or a pharmaceutically acceptable salt, solvate,
hydrate,
crystal form,
tautomer or
diastereomer thereof, wherein: A is a tumor-
directed unit with a molecular weight of 3000 Da or less and is a PSMA-binding unit; B is a spacer; C is a splittable or non-splittable left; D is a self-destructing spacer; c and d can each be 0 or an integer of 1 or more; preferably 0, 1, 2 or 3; wherein each occurrence of B, C and D may be in any order; and wherein each of E-a1 and E-c1 is a TLR7
agonist unit which is a structure of the formula E-a1 or E-c1 respectively. This includes: where Z a1 C3-Alkynyl is; U 1 -W 1Selected from: and R is selected from H, C 1-3 -
Alkyl, C 1-3 -Haloalkyl and C 1-3 -Heteroalkyl; and R 1 selected from C 1-8 -
Alkyl, C 2-8 -Cycloalkyl, (C 3-6 -Cycloalkyl) C 1-3 -
alkyl, C 1-7 -Heteroalkyl, C 2-7 -Cycloheteroalkyl, -C (=O) NH (C 1-3 -
alkyl), -C 1-3 -
Alkyl (C=O) OME, -C(=O)NH (C 2-8 -Cycloalkyl), (C 2-7 -Cycloheteroaryl) C 1-3 -
alkyl and (C 6-10 -
Aryl) C 1-3 -alkyl; each optionally substituted with one or more substituents, preferably selected from OH, CH3, OMe, CN, -C(=O)Me, F2CH, SO2Me and
halogen.