Imidazo[1,2-b]pyridazine analogues as anxiolytics and cognition enhancers
The present invention provides a compound of formula I: wherein X 1 represents hydrogen, halogen, C 1-6 alkyl, trifluoromethyl or C 1-6 alkoxy; X 2 represents hydrogen or halogen; Y represents a chemical bond, an oxygen atom, or a —NH— linkage; Z represents an optionally substituted aryl or heteroaryl group; R 1 represents hydrogen, hydrocarbon, a heterocyclic group, halogen, cyano, trifluoromethyl, nitro, —OR a , —SR a , —SOR a , —SO 2 R a , —SO 2 NR a R b , —NR a R b , —NR a COR b , —NR a CO 2 R b , —COR a , —CO 2 R a , —CONR a R b or —CR a ═NOR b ; and R a and R b independently represent hydrogen, hydrocarbon or a heterocyclic group; pharmaceutical compositions comprising this compound and methods of treating and/or preventing anxiety and convulsions using it.
1. A compound of formula IIB, or a pharmaceutically acceptable salt thereof:
wherein:
R 6 represents hydrogen or fluoro;
R 11 represents trifluoromethyl or methyl;
X 11 represents hydrogen or fluoro; and
X 12 represents hydrogen or fluoro.
2. The compound of claim 1 wherein R 6 is hydrogen.
3. The compound of claim 1 wherein R 6 is fluoro which is attached to the phenyl ring at the 4-, 5- or 6-position (relative to the cyano group at the 2-position of the phenyl ring).
4. The compound of claim 1 wherein R 11 is trifluoromethyl.
5. The compound of claim 1 wherein R 11 is methyl.
6. The compound of claim 1 wherein X 11 is fluoro.
7. The compound of claim 1 wherein X 12 is hydrogen.
8. The compound of claim 1 wherein X 12 is fluoro.
9. A pharmaceutical composition comprising the compound of claim 1 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient.
10. A compound which is selected from:
3′-(7-Methylimidazo[1,2-b]pyridazin-3-yl)biphenyl-2-carbonitrile, or a pharmaceutically acceptable salt thereof.
11. A pharmaceutical composition comprising the compound of claim 10 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient.