Histamine h3 receptor agents, preparation and therapeutic uses

A compound structurally represented by Formula I

• or a pharmaceutically acceptable salt thereof, wherein:
• Y independently represents carbon;
• X independently represents carbon or nitrogen;
• R1 is independently
• -halogen, —CN, —NO2, —(C1-C7) alkyl(optionally substituted with 1 to 3 halogens), —(C3-C8) cycloalkyl, —(C1-C7) alkyl-S(O)2—(C1-C3) alkyl, —(C1-C7) alkyl-C(O)—O—R3, —(C1-C7) alkyl-S(O)2-phenyl(R2)(R2)(R2), —(C1-C7) alkyl-S—(C1-C7) alkyl, —(C1-C7) alkyl-(C3-C8) cycloalkyl, —(C1-C7) alkyl-phenyl(R2)(R2)(R2), —C(O)-phenyl(R2)(R2)(R2), —C(O)—(C1-C7) alkyl, —C(O)—(C3-C8) cycloalkyl, —(C1-C7) alkyl-C(O)-phenyl(R2)(R2)(R2), —S—(C1-C7) alkyl, —S—(C1-C7) alkyl-phenyl(R2)(R2)(R2), —S—(C3-C8) cycloalkyl-(C1-C7) alkyl, —S—(C3-C8) cycloalkyl, —S—(C2-C7) alkenyl, —S-phenyl(R2)(R2)(R2), —SO2-phenyl(R2)(R2)(R2), —SO2R7, —S(O)R7, —(C2-C7) alkenyl, —(C3-C8) cycloalkenyl, —(C2-C7) alkenyl-S(O)2—(C1-C3) alkyl, —(C2-C7) alkenyl-C(O)—O—R3, —(C2-C7) alkenyl-S(O)2-phenyl(R2)(R2)(R2), —(C2-C7) alkenyl-S—(C1-C7) alkyl, —(C2-C7) alkenyl-(C3-C8) cycloalkyl, or —(C2-C7) alkenyl-phenyl(R2)(R2)(R2);
• R2 is independently at each occurrence
• —H, -halogen, —(C1-C7) alkyl(optionally substituted with 1 to 3 halogens), —C(O)R7, —C(O)OR7, —C(O)(C3-C8)cycloalkyl, —OCF3, —OR7, —SR7, —SO2R7, —SO2CF3, or —S(O)R7;
• R3 is independently at each occurrence
• —H, or —(C1-C3) alkyl(optionally substituted with 1 to 3 halogens);
• R4 and R5 are independently at each occurrence
• —H, -halogen, —(C1-C3) alkyl(optionally substituted with 1 to 3 halogens), or —OR3, provided that when X is nitrogen, then R4 or R5 are not attached to X;
• R6 is independently at each occurrence
• —H, -halogen, —CF3, —(C1-C3) alkyl(optionally substituted with 1 to 3 halogens), or —OR3;
• and
• R7 is independently at each occurrence
• —H, —(C1-C7) alkyl(optionally substituted with 1 to 3 halogens), or —(C2-C7) alkenyl.