Patent ID: 7858652

Claim:
A compound of formula I, wherein R 1 is selected from the group consisting of hydrogen and lower alkyl; each R 2 is independently selected from the group consisting of hydrogen and lower alkyl; each R 3 is independently selected from the group consisting of lower alkoxy, phenyloxy, and benzyloxy; R 4 is selected from the group consisting of hydrogen and lower alkyl; X is selected from the group consisting of —CH 2 —, —CH— and —O—; Y is selected from the group consisting of —CH 2 —, —CH 2 CH 2 —, and a bond; with the proviso that, when X is —O—, Y is —CH 2 —; Z is selected from the group consisting of —CH 2 — and —CH—; m is 1 or 2; and n is 1 or 2; or a pharmaceutically-acceptable acid-addition salt thereof.