Chloride channel opener

1. A method for treating disease by opening ClC channels in a mammalian subject, wherein the disease is selected from the group consisting of myotonia atrophica, calculus renum, constipation, anxiety, insomnia, epilepsia, anesthesia, asthma, bronchitis and neuropathy, which comprises administering an effective amount of a prostaglandin compound to the subject, wherein said prostaglandin compound is the compound as shown by the following general formula (I):

wherein L, M and N are hydrogen atom, hydroxy, halogen atom, lower alkyl, hydroxy(lower)alkyl, or oxo, wherein at least one of L and M is a group other than hydrogen, and the five-membered ring of formula (I) may have one or more double bonds;

A is —CH 2 OH, —COCH 2 OH, —COOH or a pharmaceutically acceptable salt, ether, ester or amide thereof;

B is —CH 2 —CH 2 —, —CH═CH— or —C≡C—;

Zis

wherein R 4 and R 5 are hydrogen, hydroxy, halogen, lower alkyl, lower alkoxy or hydroxy(lower)alkyl, wherein R 4 and R 5 are not hydroxy and lower alkoxy at the same time;

R 1 is a saturated or unsaturated bivalent lower or medium aliphatic hydrocarbon residue, which is unsubstituted or substituted with halogen, alkyl, hydroxy, oxo, or aryl, and at least one carbon atom in the aliphatic hydrocarbon is optionally substituted by oxygen, nitrogen or sulfur; and

Ra is a saturated or unsaturated lower or medium aliphatic hydrocarbon residue, which is unsubstituted or substituted with halogen, oxo, hydroxy, lower alkoxy, lower alkanoyloxy, cyclo(lower)alkyl, cyclo(lower)alkyloxy, aryl, or aryloxy; cyclo(lower)alkyl; cyclo(lower)alkyloxy; aryl; or aryloxy.

2. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or dihalogen-prostaglandin compound.

3. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or dihalogen-prostaglandin compound.

4. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or difluoro-prostaglandin compound.

5. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or difluoro-prostaglandin compound.

6. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or dihalogen-prostaglandin E compound.

7. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or dihalogen-prostaglandin E compound.

8. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-16,16-difluoro prostaglandin E 1 compound.

9. The method as described in claim 1 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-prostaglandin E1 compound or 13,14-dihydro-15-keto-16,16-difluoro-18-methyl-prostaglandin E 1 compound.

10. The method as described in claim 1 , wherein A is represented by the formula (V):

—CONR′R″ (V)

wherein R′ and R″ are hydrogen, lower alkyl, aryl, alkyl- or aryl-sulfonyl, lower alkenyl or lower alkynyl.

11. The method as described in claim 10 , wherein the prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-PGE 1 N-ethyl amide.

12. The method as described in claim 10 , wherein the prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-PGF 1α N-ethyl amide.

13. A method for treating cystic fibrosis, which comprises by administrating an effective amount of a prostaglandin compound to a subject in need of such treatment, wherein said prostaglandin compound is a compound as shown by the following general formula (I):

wherein L, M and N are hydrogen atom, hydroxy, halogen atom, lower alkyl, hydroxy(lower)alkyl, or oxo, wherein at least one of L and M is a group other than hydrogen, and the five-membered ring of formula (I) may have one or more double bonds;

A is —CH 2 OH, —COCH 2 OH, —COOH or a pharmaceutically acceptable salt, ether, ester or amide thereof;

B is —CH 2 —CH 2 —, —CH═CH— or —C≡C—;

Z is

wherein R 4 and R 5 are hydrogen, hydroxy, halogen, lower alkyl, lower alkoxy or hydroxy(lower)alkyl, wherein R 4 and R 5 are not hydroxy and lower alkoxy at the same time;

R 1 is a saturated or unsaturated bivalent lower or medium aliphatic hydrocarbon residue, which is unsubstituted or substituted with halogen, alkyl, hydroxy, oxo, or aryl, and at least one carbon atom in the aliphatic hydrocarbon is optionally substituted by oxygen, nitrogen or sulfur; and

Ra is a saturated or unsaturated lower or medium aliphatic hydrocarbon residue, which is substituted with halogen, oxo, hydroxy, lower alkoxy, or lower aryloxy; cyclo(lower)alkyl; cyclo(lower)alkyloxy; aryl; or aryloxy, provided that Ra is substituted by halogen.

14. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or dihalogen-prostaglandin compound.

15. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or dihalogen-prostaglandin compound.

16. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or difluoro-prostaglandin compound.

17. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or difluoro-prostaglandin compound.

18. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-16-mono or dihalogen-prostaglandin E compound.

19. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16-mono or dihalogen-prostaglandin E compound.

20. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-16,16-difluoroprostaglandin E 1 compound.

21. The method as described in claim 13 , wherein said prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-prostaglandin E 1 compound or 13,14-dihydro-15-keto-16,16-difluoro-18-methyl-prostaglandin E 1 compound.

22. The method as described in claim 13 , wherein A is represented by the formula (V):

—CONR′R″ (V)

wherein R′ and R″ are hydrogen, lower alkyl, aryl, alkyl- or aryl-sulfonyl, lower alkenyl or lower alkynyl.

23. The method as described in claim 22 , wherein the prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-PGE 1 N-ethyl amide.

24. The method as described in claim 22 , wherein the prostaglandin compound is 13,14-dihydro-15-keto-16,16-difluoro-PGF 1α N-ethyl amide.

25. A method for treating a condition associated with reduced chloride ion permeability wherein the condition is selected from the group consisting of myotonia atrophica, calculus renum, anxiety, insomnia, epilepsia, anesthesia and neuropathy, which comprises administering to a subject in need thereof an effective amount of a prostaglandin compound as shown by the following general formula (I):

wherein L, M and N are hydrogen atom, hydroxy, halogen atom, lower alkyl, hydroxy(lower)alkyl, or oxo, wherein at least one of L and M is a group other than hydrogen, and the five-membered ring of formula (I) may have one or more double bonds;

A is —CH 2 OH, —COCH 2 OH, —COGH or a pharmaceutically acceptable salt, ether, ester or amide thereof;

B is —CH 2 —CH 2 —, —CH═CH— or —C≡C—;

Z is

wherein R 4 and R 5 are hydrogen, hydroxy, halogen, lower alkyl, lower alkoxy or hydroxy(lower)alkyl, wherein R 4 and R 5 are not hydroxy and lower alkoxy at the same time;

R 1 is a saturated or unsaturated bivalent lower or medium aliphatic hydrocarbon residue, which is unsubstituted or substituted with halogen, alkyl, hydroxy, oxo or aryl, and at least one carbon atom in the aliphatic hydrocarbon is optionally substituted by oxygen, nitrogen or sulfur; and

Ra is a saturated or unsaturated lower or medium aliphatic hydrocarbon residue, which is unsubstituted or substituted with halogen, oxo, hydroxy, lower alkoxy, lower alkanoyloxy, cyclo(lower)alkyl, cyclo(lower)alkyloxy, aryl, or aryloxy; cyclo(lower)alkyl; cyclo(lower)alkyloxy; aryl; or aryloxy.