Patent ID: 8563577

Claim:
A compound of formula (I): wherein: R 1 is selected from the group consisting of (C 1 -C 6 )alkyl, aryl, (C 3 -C 8 )cycloalkyl, aryl(C 1 -C 6 )alkyl, and heteroaryl, optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NH 2 , —NO 2 , —CN, —CONHR 5 , —CON(R 5 ) 2 , —NHCOR 5 , —COR 5 , —CO 2 R 5 , (C 1 -C 6 )alkylsulfanyl, (C 1 -C 10 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 1 -C 6 )alkoxy, and (C 1 -C 6 )haloalkoxy; R 2 is be H or (C 1 -C 6 )alkyl optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NH 2 , —NO 2 , —CN, —ONHR 5 , —CON(R 5 ) 2 , —NHCOR 5 , —COR 5 , —CO 2 R 5 , (C 1 -C 6 )alkylsulfanyl, (C 1 -C 6 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 1 -C 6 )alkoxy, and (C 1 -C 6 )haloalkoxy; R 3 is H or is selected from the group consisting of (C 1 -C 6 )alkyl, aryl, (C 3 -C 8 )cycloalkyl, and heteroaryl, optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NH 2 , —NO 2 , —CN, —CONHR 5 , —CON(R 5 ) 2 , —CO 2 R 5 , (C 1 -C 6 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 1 -C 6 )alkoxy, and (C 1 -C 6 )haloalkoxy; R 6 represents a group of formula (i): wherein A − is a physiologically acceptable anion; R 4 is a group of formula (Y): —(CH 2 ) p —P—(CH 2 ) q —W (Y) wherein p is 0 or an integer of 1 to 4; q is 0 or an integer of 1 to 4; P is a heteroaryl, optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NO 2 , —CN, —CON(R 5 ) 2 , —NH 2 , —NHCOR 5 , —CO 2 R 5 , (C 1 -C 6 )alkylsulfanyl, (C 1 -C 6 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, and (C 1 -C 6 )alkoxy; W is selected from the group consisting of aryl, (C 3 -C 8 )cycloalkyl and heteroaryl, optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NH 2 , —NO 2 , —CN, —CONHR 5 , —CON(R 5 ) 2 , —NHCOR 5 , —COR 5 , —CO 2 R 5 , (C 1 -C 6 )alkylsulfanyl, (C 1 -C 6 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 1 -C 6 )alkoxy, and (C 1 -C 6 )haloalkoxy; R 5 is H or is selected from the group consisting of (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 2 -C 6 )alkenyl, (C 3 -C 8 )cycloalkyl, heteroaryl, and aryl optionally substituted by one or more substituents selected from the group consisting of halogen atoms, —OH, oxo, —SH, —NH 2 , —NO 2 , —CN, —CONH 2 , —COOH, (C 1 -C 10 )alkoxycarbonyl, (C 1 -C 6 )alkylsulfanyl, (C 1 -C 6 )alkylsulfinyl, (C 1 -C 6 )alkylsulfonyl, (C 1 -C 6 )alkyl, (C 1 -C 6 )haloalkyl, (C 1 -C 6 )alkoxy, and (C 1 -C 6 )haloalkoxy; or a pharmaceutically acceptable salt thereof.