Patent ID: 6872720

Claim:
A compound of formula I, or a pharmaceutically acceptable salt thereof: wherein Y represents C 1-6 alkyl; Z represents halogen; or C 1-6 alkyl, C 3-7 cycloalkyl, C 4-7 cycloalkenyl, C 6-8 bicycloalkyl, aryl, C 3-7 heterocycloalkyl, heteroaryl or di(C 1-6 )alkylamino, any of which groups may be optionally substituted; R 1 represents C 3-7 cycloalkyl, phenyl, furyl, thienyl, pyridinyl or pyrazinyl, any of which groups may be optionally substituted; and R 2 represents C 3-7 cycloalkyl(C 1-6 )alkyl, aryl(C 1-6 )alkyl or heteroaryl(C 1-6 )alkyl, any of which groups may be optionally substituted.