Patent ID: 8084612

Claim:
A compound of formula I(a): or a pharmaceutically acceptable salt thereof, wherein: X is S or O; R 1 is —(C 1 -C 10 alkyl), —O(C 1 -C 10 alkyl), —NH(C 1 -C 4 alkyl), —N(C 1 -C 4 alkyl) 2 , R 2 is —(C 1 -C 10 alkyl), —(C 3 -C 8 ) cycloalkyl, phenyl, naphthyl, anthryl, phenanthryl, or -(5 to 7 membered) heteroaryl, each being unsubstituted or substituted with 1, 2, or 3 R 3 groups; each R 3 is independently -halo, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —CN, —OH, —NO 2 , —NH 2 , —NH(C 1 -C 4 alkyl), —N(C 1 -C 4 alkyl) 2 , —(C 1 -C 10 alkyl), —O(C 1 -C 4 alkyl), —CONH 2 , —CONH(C 1 -C 4 alkyl), or —CON(C 1 -C 4 alkyl) 2 ; each R 4 is independently -halo, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —OH, —(C 1 -C 4 alkyl), or —O(C 1 -C 4 alkyl); R 5 is —H, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —(C 1 -C 10 alkyl), —(CH 2 ) r O(C 1 -C 4 alkyl), —(CH 2 ) r NH(C 1 -C 4 alkyl), or —(CH 2 ) r N(C 1 -C 4 alkyl) 2 , where r is an integer selected from the group consisting of 1, 2, 3, and 4; each halo is independently —F, —Cl, —Br, or —I; k is an integer selected from the group consisting of 2, 3, and 4; and each m is independently an integer selected from the group consisting of 0, 1, 2, 3, and 4.