Heterocyclic compound
The present invention provides a compound represented by the formula (1): wherein each symbol is as defined in the specification, or a salt thereof, a prodrug of the compound or a salt thereof, a medicament containing the compound or a salt thereof, the medicament which is a phosphodiesterase 10A inhibitor, and a medicament which is for preventing or treating schizophrenia.
1. A compound represented by formula (1)
wherein
R 1 is an optionally substituted C 1-6 alkoxy group,
R 2 is a hydrogen atom or an optionally substituted C 1-6 alkyl group,
R 3 is selected from the group consisting of the following fused rings
wherein
ring Aa is an optionally substituted 5- or 6-membered heterocycle wherein the substituents for ring Aa are optionally bonded to form a ring; and
the benzene ring or pyridine ring contained in the fused ring is optionally substituted, or
wherein
ring A b is a substituted pyridine ring, an optionally substituted pyrazole ring, an optionally substituted thiazole ring, an optionally substituted pyrazine ring, an optionally substituted pyridazine ring, an optionally substituted pyrimidine ring or an optionally substituted imidazole ring, and
R 4 is an optionally substituted C 1-6 alkyl group or an optionally substituted phenyl group, provided that the following compounds:
a compound wherein R 1 is a C 1-6 alkoxy group substituted by substituent(s) having optionally substituted cyclic group(s),
5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)-1-(2,2,6-trifluoro-1,3-benzodioxol-5-yl)pyridazin-4(1H)-one, and
5-methoxy-1-(2,2,3,3,7-pentafluoro-2,3-dihydro-1,4-benzodioxin-6-yl)-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one
are excluded,
or a salt thereof.
2. The compound or salt of claim 1 , wherein R 3 is
wherein
R 5 is a substituent, and
Aa, the benzene ring and the pyridine ring are as defined in claim 1 .
3. The compound or salt of claim 2 , wherein R 5 is a halogen atom or an optionally substituted C 1-6 alkoxy group.
4. The compound or salt of claim 1 , wherein R 3 is
wherein ring A b is a substituted pyridine ring or a substituted pyrazole ring.
5. 5-{3-[1-(3-Chlorophenyl)-1H-pyrazol-5-yl]-5-methoxy-4-oxopyridazin-1(4H)-yl}-4-fluoro-1,3,3-trimethyl-1,3-dihydro-2H-indol-2-one or a salt thereof.
6. 1-(Cyclopropylmethyl)-4-fluoro-5-[5-methoxy-4-oxo-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-1(4H)-yl]-3,3-dimethyl-1,3-dihydro-2H-indol-2-one or a salt thereof.
7. 1-[1-(1-Cyclopropylethyl)-1H-pyrazol-4-yl]-5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one or a salt thereof.
8. 5-Methoxy-1-[2-methoxy-6-(3,3,4,4-tetrafluoropyrrolidin-1-yl)pyridin-3-yl]-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one or a salt thereof.
9. 1-[6-(3,4-difluoro-1H-pyrrol-1-yl)-2-methoxypyridin-3-yl]-5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one or a salt thereof.
10. A pharmaceutical composition comprising the compound or salt of claim 1 , and a pharmacologically acceptable carrier.
11. The pharmaceutical composition of claim 10 , which is a phosphodiesterase 10A inhibitor.
12. A method for treating schizophrenia which comprises administering an effective amount of the compound or salt of claim 1 to a mammal.