1H-imidazo[4,5-d]thieno[3,2-b]pyridine based tricyclic compounds and pharmaceutical compositions comprising same

A compound of formula (I),

• or pharmaceutically acceptable salt thereof, wherein
• R1 is selected from C1-3 alkyl;
• R2 is hydrogen;
• R5 is —NR3R4;
• R3 and R4 are independently selected from
• (a) hydrogen, or
• (b) alkyl;
• R6 is
• aryl, which may be optionally independently substituted as valence allows with one or more Z1d, Z2d and Z3d;
• R7 is
• (a) hydrogen, or halo,
• Z1d, Z2d and Z3d are independently
• (1) H
• (7) —U1-halo,
• (10) —U1—NY2Y3,
• (11) —U1—N(Y4)—C(O)—Y1,
• Y1, Y2, Y3, Y4 and Y5
• (1) are each independently hydrogen, alkyl, (alkoxy)alkyl, cycloalkyl, (cycloalkyl)alkyl, aryl, (aryl)alkyl, piperidinyl, pyrrolidinyl, thiadiazolyl, pyridinyl, pyradizinyl, pyrazinyl, isoxazolyl, imidazolyl, or (imidazolyl)alkyl, any of which may be optionally independently substituted as valence allows with one or more Z4, Z5 and Z6;
• or
• Z4, Z5, and Z6 are optional substituents at each occurrence independently selected from
• (1) H
• (2) alkyl;
• (3) —U1—O—Y5a,
• (8) —U1-cyano,
• (10) —U1—NY2aY3a,
• (11) —U1—N(Y4a)—C(O)—Y1a,
• (16) —U1—N(Y4a)—S(O)2—Y1a,
• Y1a, Y2a, Y3a, Y4a and Y5a
• (1) are each independently hydrogen, or alkyl;
• U1 is independently
• (1) a single bond,
• (2) alkylene.