Substituted piperidine compounds and methods of their use

1. A compound of formula I:

wherein:

R 1 is H or alkyl;

R 2a is alkyl or alkenyl;

R 2b is H, alkyl or alkenyl;

R 3 is H, alkyl, alkenyl, aryl, cycloalkyl, cycloalkenyl, cycloalkylalkyl, cycloalkenylalkyl, or aralkyl;

R 4 is:

H,

aryl (optionally substituted by one or more substituents selected from —OH, nitro, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, —N(R 6a )(R 6b ), alkoxycarbonyl, aryloxy, aryl, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)),

aralkyl,

alkyl,

alkenyl, or

alkynyl,

which latter three groups are optionally substituted by one or more substituents selected from —OR 6c , —S(═O) q R 6d , —CN, halo, alkoxycarbonyl, —N(R 6a )(R 6b ), alkanoyl, alkanoyloxy, cycloalkyl, cycloalkanoyl, —N(R 6e )S(═O) 2 R 7a , —P(═O)OR 7b OR 7c , Het 1 , and aryl (which latter group is optionally substituted by one or more substituents selected from —OH, nitro, —N(R 6a )(R 6b ), halo, —CN, —CH 2 CN, —C(═O)NH 2 , CO 2 H, —CHO, aryl, alkyl, alkoxy, aralkoxy, aryloxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms));

R 6a , R 6b , R 6c , R 6d , and R 6e , are each independently H, Het 2 , alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, or aryl (which latter six groups are optionally substituted by one or more substituents selected from OH, nitro, halo, —NHC(═O)R 3 , —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, alkoxycarbonyl, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms));

R 5 is —(CH 2 ) y (CHR 8 ) j (CHR 8a ) z W;

R 8 is each independently aryl (optionally substituted by one or more substituents selected from —OH, nitro, aryl, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, —N(R 6a )(R 6b ), alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)), cycloalkyl, alkyl, alkenyl or alkynyl wherein said alkyl, alkenyl or alkynyl groups are optionally substituted by one or more substituents selected from —OR 6c , —S(O) q R 6d , —CN, halo, —N(R 6a )(R 6b ), —CO 2 H, —C(═O)NH 2 , alkoxycarbonyl, alkanoyl, alkanoyloxy, cycloalkyl, cycloalkanoyl, —N(R 6e )S(═O) 2 R 7a , —P(═O)OR 7b OR 7c , Het 1 , and aryl (which latter group is optionally substituted by one or more substituents selected from —OH, nitro, amino, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, aroyl, aryl, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms));

R 8a is each independently H, aryl (optionally substituted by one or more substituents selected from —OH, nitro, aryl, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, —N(R 6a )(R 6b ), alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)), cycloalkyl, alkyl, alkenyl or alkynyl wherein said alkyl, alkenyl or alkynyl groups are optionally substituted by one or more substituents selected from —OR 6c , —S(O) q R 6d , —CN, halo, amino, —CO 2 H, —C(═O)NH 2 , alkoxycarbonyl, alkanoyl, alkanoyloxy, cycloalkyl, cycloalkanoyl, —N(R 6e )S(═O) 2 R 7a , —P(═O)OR 7b OR 7c , Het 1 , and aryl (which latter group is optionally substituted by one or more substituents selected from —OH, nitro, amino, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, aroyl, aryl, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms));

W is —C(═O)OR 9 , —C(═O)N(R 10a )(R 10b ), or —P(═O)OR 7b OR 7c ;

R 9 is H, alkyl, alkenyl, phenyl, cycloalkyl, cycloalkenyl, cycloalkylalkyl, cycloalkenylalkyl, or aralkyl;

R 10a and R 10b , each independently represent H, alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, Het 3 , or aryl (which latter seven groups are optionally substituted by one or more substituents selected from —OH, nitro, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)); or R 10a and R 10b when taken together with the nitrogen atom to which they are attached form a 4- to 8-membered heterocycloalkyl ring, wherein said heterocycloalkyl ring is optionally fused to an aromatic ring, and wherein said heterocycloalkyl ring, or the aromatic ring to which it is optionally fused, is each independently optionally substituted by one or more substituents selected from —OH, alkyl, or alkoxy; and wherein the heterocycloalkyl ring is also optionally interrupted by one or more O, S or N(R 12 ) groups;

R 7a , R 7b , R 7c , and R 7d , are each independently H, alkyl, cycloalkyl, alkaryl, aralkyl or aryl, which latter five groups are optionally substituted by one or more substituents selected from alkyl, alkoxy, —OH, nitro, amino and halo;

Het 1 , Het 2 and Het 3 each independently represent a 3- to 8-membered heterocyclic ring, wherein said heterocyclic ring contains at least one heteroatom selected from oxygen, sulfur, nitrogen or combinations thereof, wherein said heterocyclic ring is optionally fused to an aromatic ring, and wherein said heterocyclic ring, or the aromatic ring to which it is optionally fused, is each independently optionally substituted by one or more substituents selected from —OH, ═O, nitro, amino, halo, —CN, —CO 2 H, aryl, alkyl, alkoxy and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms);

R 11 represents H, alkyl, cycloalkyl, cycloalkylalkyl, or aralkyl;

R 12 represents H, alkyl, cycloalkyl, cycloalkylalkyl, or aralkyl;

j is the integer 0, 1, 2, 3, or 4;

m is the integer 0, 1, 2, 3, or 4;

q is the integer 0, 1, or 2;

y is the integer 0, 1, 2, 3, 4, or 5; and

z is the integer 0, 1, 2, 3, or 4;

with the provisos that:

when j and z are each the integer 0, y must be the integer 5; and

when R 8a is H and i is 0, the sum of y+z must be the integer 5;

or a stereoisomer, prodrug, pharmaceutically acceptable salt, hydrate, solvate, acid hydrate, N-oxide or isomorphic crystalline form thereof.

2. A compound according to claim 1 , wherein R 1 is H.

3. A compound according to claim 1 , wherein R 2a and R 2b are trans to each other.

4. A compound according to claim 1 , of formula II:

5. A compound according to claim 1 , wherein R 2a and R 2b are each methyl.

6. A compound according to claim 1 , of formula III:

wherein:

R 3 is H, alkyl, or aralkyl.

7. A compound according to claim 1 , of formula IV:

wherein:

R 3 is H, alkyl, or aralkyl.

8. A compound according to claim 7 , wherein R 4 is H.

9. A compound according to claim 7 , wherein R 3 is:

10. A compound according to claim 7 , of formula V:

11. A compound according to claim 10 , wherein R 4 is H.

12. A compound according to claim 10 , of formula VIa:

13. A compound according to claim 10 , of formula VIb:

14. A compound according to claim 12 or claim 13 , wherein W is —CO 2 H, and R 2a and R 2b are each methyl.

15. A compound according to claim 12 or claim 13 , wherein R 8 is alkyl substituted with aryl, optionally substituted by one or more substituents selected from —OH, nitro, amino, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, aroyl, aryl, —N(R 6a )(R 6b ), alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms).

16. A compound according to claim 15 , wherein R 8 is optionally substituted benzyl.

17. A compound according to claim 16 , wherein said benzyl is substituted by one or more substituents selected from —OH, nitro, halo, aroyl, or aryl.

18. A compound according to claim 12 or claim 13 , wherein R 3 is:

19. A compound according to claim 1 , wherein W is —CO 2 H.

20. A compound according to claim 1 , wherein R 4 is benzyl.

21. A compound according to claim 1 , wherein R 4 is H.

22. A compound according to claim 1 , wherein m is the integer 1.

23. A compound according to claim 1 , wherein R 4 is benzyl and m is the integer 1.

24. A compound according to claim 1 , wherein R 4 is benzyl, m is the integer 1, and W is —CO 2 H.

25. A compound according to claim 1 , wherein R 3 is H, m is the integer 1, and R 4 is aryl (optionally substituted by one or more substituents selected from —OH, nitro, halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, —N(R 6a )(R 6b ), alkoxycarbonyl, aryloxy, aryl, alkyl, alkoxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)), alkyl, alkenyl, or alkynyl, which latter three groups are optionally substituted by one or more substituents selected from —OR 6c , —S(═O) q R 6d , —CN, halo, alkoxycarbonyl, amino, alkanoyl, alkanoyloxy, cycloalkyl, cycloalkanoyl, —N(R 6e )S(═O)2R 7a , P(═O)OR 7b OR 7c , Het 1 , and aryl (which latter group is optionally substituted by one or more substituents selected from —OH, nitro, N(R 6a )(R 6b ), halo, —CN, —CH 2 CN, —C(═O)NH 2 , —CO 2 H, —CHO, aryl, alkyl, alkoxy, aralkoxy, aryloxy, and alkanoyl (which latter three groups are optionally substituted by one or more halo atoms)).

26. A pharmaceutical composition, comprising:

a pharmaceutically acceptable carrier; and

an effective amount of a compound according to claim 1 .

27. A method for preventing or treating ileus, comprising the step of:

administering to a patient in need of such treatment, a composition comprising an effective amount of a compound according to claim 1 .