Toll-like receptor 7 (TLR7) agonists having heteroatom-linked aromatic moieties, conjugates thereof, and methods and uses therefor
Compounds having a structure according to formula (I) or (II) where R 1 , R 2 , R 3 , R 4 , Ar and X 1 are as defined herein, are agonists for the Toll-like receptor 7 (TLR7) and can be used as adjuvants for stimulating the immune system. Some such compounds can be used in conjugates for targeted delivery to the organ or tissue of intended action.
1. A compound represented by formula (I) or (II)
wherein
R 1 is (C 1 -C 5 alkyl)O, (C 1 -C 2 alkyl)O(CH 2 ) 2-3 O, (C 1 -C 5 alkyl)C(═O)O, (C 1 -C 5 alkyl)NH, (C 1 -C 2 alkyl)O(CH 2 ) 2-3 NH, or (C 1 -C 5 alkyl)C(═O)NH;
R 2 is, independently for each occurrence thereof, H, C 1 -C 3 alkyl, halo, O(C 1 -C 3 alkyl), CN, or NO 2 ;
X is, independently for each occurrence thereof, CR 2 or N;
R 3 is O, S, NH, or N(C 1 -C 3 alkyl);
Ar is
where one of Y, Y′ and Y″ is selected from —O—, —S—, —NH— and —N(C 1 -C 3 alkyl)- and the other two of Y, Y′, and Y″ are selected from ═N— and ═CR 2 —;
R 4 is H, C 1 -C 3 alkyl, halo, O(C 1 -C 3 alkyl), CN, NO 2 , or (CH 2 ) x R 5 , where the subscript x is 1, 2, 3, or 4; and
R 5 is H, halo, OH, CN, NH 2 , NH(C 1 -C 5 alkyl), N(C 1 -C 5 alkyl) 2 , NH(C 3 -C 6 cycloalkyl), NH(C 4 -C 8 bicycloalkyl), NH(C 6 -C 10 spirocycloalkyl), N(C 3 -C 6 cycloalkyl) 2 , NH(CH 2 ) 1-3 (aryl), N((CH 2 ) 1-3 (aryl)) 2 , a cyclic amine moiety having the structure
a 6-membered aromatic or heteroaromatic moiety or a 5-membered heteroaromatic moiety;
wherein
an alkyl, cycloalkyl, bicycloalkyl, spriocycloalkyl, cyclic amine, 6-membered aromatic or heteroaromatic, or 5-membered heteroaromatic moiety is optionally substituted with one or more substituents selected from OH, halo, CN, (C 1 -C 3 alkyl), O(C 1 -C 3 alkyl), C(═O)(Me), SO 2 (C 1 -C 3 alkyl), C(═O)(Et), NH 2 , NH(Me), N(Me) 2 , NH(Et), N(Et) 2 , and N(C 1 -C 3 alkyl) 2 ; and
a cycloalkyl, bicycloalkyl, spiroalkyl, or cyclic amine moiety may have a CH 2 group replaced by O, S, NH, N(C 1 -C 3 alkyl), or N(Boc).
2. A compound according to claim 1 , represented by formula (I′)
wherein each X′ is independently CH or N.
3. A compound according to claim 2 , wherein R 4 is CH 2 R 5 and R 5 is OH, Cl,
4. A compound according to claim 1 , represented by formula (Ia)
5. A compound according to claim 4 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
6. A compound according to claim 1 , represented by formula (Ib)
7. A compound according to claim 6 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
8. A compound according to claim 1 , represented by formula (Ic)
9. A compound according to claim 8 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
10. A compound according to claim 1 , represented by formula (Id)
11. A compound according to claim 10 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
12. A compound according to claim 1 , represented by formula (Ie)
13. A compound according to claim 1 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
14. A compound according to claim 1 , represented by formula (If)
15. A compound according to claim 14 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
16. A compound according to claim 1 , represented by formula (IIa)
17. A compound according to claim 16 , wherein R 1 is n-BuO, x is 1, and R 5 is OH, Cl,
18. A compound according to claim 1 , having a structure represented by formula (Ig):
19. A method of treating a subject suffering from a condition amenable to treatment by activation of Toll-like Receptor 7, comprising administering to such subject a therapeutically effective amount of a compound according to claim 1 ; wherein the condition is selected from fibrosis, inflammatory disorders and pathogenic infections.