Drug conjugates of ion channel modulating compounds

1. A drug conjugate comprising a drug moiety and an ion channel modulating compound, wherein the drug conjugate has the following formula (DC-I), or a pharmaceutically acceptable salt thereof:

wherein:

X is selected from a direct bond, —C(R 6 ,R 14 )—Y— and —C(R 13 )═CH—, with the proviso that when X is a direct bond and A is formula (III), then at least one of R 7 , R 8 and R 9 is not hydrogen;

Y is selected from a direct bond, O, S and C 1 -C 4 alkylene;

R 13 is selected from hydrogen, C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, aryl and benzyl;

R 1 and R 2 , taken together with the nitrogen atom to which they are directly attached in formula (DC-I), form a ring denoted by formula (DC-II-Z):

wherein the ring of formula (DC-II-Z) is formed from the nitrogen as shown as well as three to nine additional ring atoms independently selected from carbon, nitrogen, oxygen, and sulfur; where any two adjacent ring atoms may be joined together by single or double bonds, and where any one or more of the additional carbon ring atoms may be substituted with one or two substituents selected from hydrogen, hydroxy, C 1 -C 3 hydroxyalkyl, oxo, C 2 -C 4 acyl, C 1 -C 3 alkyl, C 2 -C 4 alkylcarboxy, C 1 -C 3 alkoxy, C 1 -C 20 alkanoyloxy, or may be substituted to form a spiro five- or six-membered heterocyclic ring containing one or two heteroatoms selected from oxygen and sulfur; and any two adjacent additional carbon ring atoms may be fused to a C 3 -C 8 -carbocyclic ring, and any one or more of the additional nitrogen ring atoms may be substituted with substituents selected from hydrogen, C 1 -C 6 alkyl, C 2 -C 4 acyl, C 2 -C 4 hydroxyalkyl and C 3 -C 8 alkoxyalkyl; or

LB is a linkage group;

L is an optional linker;

DM is the drug moiety selected from;

R 3 and R 4 are independently attached to the cyclohexane ring shown in formula (DC-I) at the 3-, 4-, 5- or 6-positions and are independently selected from hydrogen, hydroxy, C 1 -C 6 alkyl and C 1 -C 6 alkoxy, and, when both R 3 and R 4 are attached to the same cyclohexane ring atom, may together form a spiro five- or six-membered heterocyclic ring containing one or two heteroatoms selected from oxygen and sulfur;

R 5 , R 6 and R 14 are independently selected from hydrogen, C 1 -C 6 alkyl, aryl and benzyl, or R 6 and R 14 , when taken together with the carbon to which they are attached, may form a spiro C 3 -C 5 cycloalkyl;

A is selected from C 5 -C 12 alkyl, a C 3 -C 13 carbocyclic ring, and ring systems selected from formulae (III), (IV), (V), (VI), (VII) and (VIII):

where R 7 , R 8 and R 9 are independently selected from bromine, chlorine, fluorine, carboxy, hydrogen, hydroxy, hydroxymethyl, methanesulfonamido, nitro, sulfamyl, trifluoromethyl, C 2 -C 7 alkanoyloxy, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 2 -C 7 alkoxycarbonyl, C 1 -C 6 thioalkyl and N(R 15 ,R 16 ) where R 15 and R 16 are independently selected from hydrogen, acetyl, methanesulfonyl and C 1 -C 6 alkyl;

where R 10 and R 11 are independently selected from bromine, chlorine, fluorine, carboxy, hydrogen, hydroxy, hydroxymethyl, methanesulfonamido, nitro, sulfamyl, trifluoromethyl, C 2 -C 7 alkanoyloxy, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 2 -C 7 alkoxycarbonyl, C 1 -C 6 thioalkyl, and N(R 15 ,R 16 ) where R 15 and R 16 are independently selected from hydrogen, acetyl, methanesulfonyl, and C 1 -C 6 alkyl;

where R 12 is selected from bromine, chlorine, fluorine, carboxy, hydrogen, hydroxy, hydroxymethyl, methanesulfonamido, nitro, sulfamyl, trifluoromethyl, C 2 -C 7 alkanoyloxy, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 2 -C 7 alkoxycarbonyl, C 1 -C 6 thioalkyl, and N(R 15 ,R 16 ) where R 15 and R 16 are independently selected from hydrogen, acetyl, methanesulfonyl, and C 1 -C 6 alkyl; and Z is selected from CH, CH 2 , O, N and S, where Z may be directly bonded to “X” as shown in formula (DC-I) when Z is CH or N, or Z may be directly bonded to R 17 when Z is N, and R 17 is selected from hydrogen, C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, aryl and benzyl;

including isolated enantiomeric and diastereomeric isomers thereof, and mixtures thereof.

2. A pharmaceutical composition comprising the drug conjugate of claim 1 and a pharmaceutically acceptable excipient.

3. The drug conjugate of claim 1 selected from the group consisting of:

4. The drug conjugate of claim 1 wherein the drug conjugate is

5. The drug conjugate of claim 1 wherein the ion channel modulating compound is a compound of formula (IA), or pharmaceutically acceptable salts thereof:

wherein, R 7 , R 8 and R 9 are independently selected from hydrogen, hydroxy and C 1 -C 6 alkoxy, including isolated enantiomeric and diastereomeric thereof, and mixtures thereof, with the proviso that R 7 , R 8 and R 9 cannot all be hydrogen.

6. The drug conjugate of claim 5 wherein the compound of formula (IA) is Compound A:

or pharmaceutically acceptable salts thereof.