Tricyclic compounds useful as angiotensin II agonists

A compound of formula I,

• 20
• wherein
• one of X1 and X2 represents —N— and the other represents —C(R1)—;
• X3 represents —N— or —C(R2)—;
• X4 represents —N— or —C(R3)—;
• R1, R2 and R3 independently represent H, C1-6 alkyl, C1-6 alkoxy, C1-6 alkoxy-C1-6-alkyl or halo;
• provided that, when X1 represents —C(R1)—, X3 represents —C(R2)— and X4 represents —C(R3)—, then R1 represents H;
• Y1, Y2, Y3, and Y4 independently represent —CH— or —CF—;
• Z1 represents —CH—, —O—, —S—, —N— or —CH═CH—;
• Z2 represents —CH—, —O—, —S— or —N—;
• provided that:
• (a) Z1 and Z2 are not the same;
• (b) when Z1 represents —CH═CH—, then Z2 may only represent —CH— or —N—;
• and
• (c) other than in the specific case in which Z1 represents —CH═CH—, and Z2 represents —CH—, when one Z1 and Z2 represents —CH—, then the other represents —O— or —S—;
• R4 represents —S(O)2N(H)C(O)R6, —S(O)2N(H)S(O)2R6, —C(O)N(H)S(O)2R6, or, when Z1 represents —CH═CH—, R4 may represent —N(H)S(O)2N(H)C(O)R7 or —N(H)C(O)N(H)S(O)2R7;
• R5 represents C1-6 alkyl, C1-6 alkoxy, C1-6 alkoxy-C1-6-alkyl or di-C1-3-alkylamino-C1-4-alkyl;
• R6 represents C1-6 alkyl, C1-6 alkoxy, C1-6 alkoxy-C1-6-alkyl, C1-3 alkoxy-C1-6-alkoxy, C1-6 alkylamino or di-C1-6alkylamino;
• and
• R7 represents C1-6alkyl,
• or a pharmaceutically-acceptable salt thereof.