Quinolizidinone carboxamide m1 receptor positive allosteric modulators

A compound of formula (I):

• wherein R1 is selected from the group consisting of
• (1) hydrogen, or
• (2) —C1-6 alkyl,
• R2 is selected from the group consisting of
• (1) hydrogen,
• (2) —C1-6 alkyl,
• (3) —C2-6 alkenyl,
• (4) —OC1-6 alkyl,
• (5) —C3-8 cycloalkyl,
• (6) —C5-8 cycloalkenyl,
• (7) a heterocyclic group having 4 to 8 ring atoms selected from C, O, N, N→O, C(═O), SO2 or S, at least one of which is O, N, N→O, SO2 or S,
• (8) heteroaryl, which is an aromatic cyclic or polycyclic group, having from five to twelve ring atoms, said ring atoms selected from C, O, N, N→O, C(═O) or S, at least one of which is O, N, N→O or S, or
• (9) —C6-10 aryl,
• wherein the alkyl, cycloalkyl, cycloalkenyl, heterocyclic, heteroaryl or aryl R2 moiety is optionally substituted by one or more
• (a) halogen,
• (b) hydroxyl,
• (c) —C1-6 alkyl,
• (d) —O—C1-6 alkyl,
• (e) —C3-8 cycloalkyl,
• (f) —C6-10 aryl,
• (g) heteroaryl, which is an aromatic cyclic or polycyclic group, having from five to twelve ring atoms, said ring atoms selected from C, O, N, N→O, C(═O), SO2 or S, at least one of which is O, N, N→O, SO2 or S, or
• (h) —(C═O)—C1-6 alkyl,
• (i) —NRARB, wherein RA and RB are selected from the group consisting of
• (i) hydrogen, or
• (ii) —C1-6 alkyl,
• or RA and RB are linked together with the nitrogen to which they are attached to form a 4-6 membered carbocyclic ring, wherein one or two of the ring carbon atoms is optionally replaced by a nitrogen, oxygen or sulfur, and the ring is optionally substituted with one or more
• (i) halogen,
• (ii) hydroxyl,
• (iii) C1-6 alkyl,
• (iv) —O—C1-6 alkyl,
• (v) —C(═O)—(O)n—C1-6 alkyl,
• or R1 and R2 are linked together with the nitrogen to which they are both attached to form a 4-8 membered saturated or unsaturated carbocyclic ring, wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur, and the carbocyclic is optionally substituted with one or more
• (a) halogen,
• (b) hydroxyl,
• (c) —C1-6 alkyl,
• (d) —O—C1-6 alkyl,
• (e) —C3-8 cycloalkyl,
• (f) —C6-10 aryl,
• (g) heteroaryl, which is an aromatic cyclic or polycyclic group, having from five to twelve ring atoms, said ring atoms selected from C, O, N, N→O, C(═O) or S, at least one of which is O, N, N→O or S, or
• (h) —(C═O)—C1-6 alkyl;
• R3 is optionally present at one or more of the phenyl moiety C atoms, and is selected from the group consisting of
• (1) —C1-6 alkyl,
• (2) —OC1-6 alkyl, or
• (3) halogen;
• R4 is selected from the group consisting of
• (1) a heterocyclic group having 4 to 8 ring atoms selected from C, O, N, N→O, C(═O), SO2 or S, at least one of which is O, N, N→O, SO2 or S,
• (2) heteroaryl, which is an aromatic cyclic or polycyclic group, having from five to twelve ring atoms, said ring atoms selected from C, O, N, N→O, C(═O) or S, at least one of which is O, N, N→O or S,
• (3) —C3-8 cycloalkyl,
• (4) —C5-8 cycloalkenyl, or
• (5) —C6-10 aryl,
• wherein the heterocyclic, heteroaryl or aryl moiety is optionally substituted with one or more
• (a) halogen,
• (b) hydroxyl,
• (c) —C1-6 alkyl,
• (d) —O—C1-6 alkyl,
• (e) —C3-8 cycloalkyl,
• (f) —C6-10 aryl,
• (g) heteroaryl, which is an aromatic cyclic or polycyclic group, having from five to twelve ring atoms, said ring atoms selected from C, O, N, N→O, C(═O) or S, at least one of which is O, N, N→O or S, or wherein the alkyl, cycloalkyl, aryl or heteroaryl moiety is optionally substituted with one or more
• (i) halogen,
• (ii) hydroxyl,
• (iii) —C1-6 alkyl, or
• (iv) —O—C1-6 alkyl.
• or a pharmaceutically acceptable salt thereof.