Patent ID: 8604019

Claim:
A compound of formula (I): or a pharmaceutically acceptable salt or stereoisomer thereof, wherein: R 1 is hydrogen or a C 1-6 alkyl; R 2 is (1) amino(CH 2 ) 2-6 ; (2) amino(CH 2 ) 1-6 difluoromethyl(CH 2 ) 1-6 ; (3) amino(CH 2 ) 1-6 fluoromethyl(CH 2 ) 1-6 ; (4) amino(CH 2 ) 0-6 oxetanyl(CH 2 ) 1-6 ; (5) amino(CH 2 ) 1-6 oxetanyl(CH 2 ) 0-6 ; or (6) pyrrolidin-3-yl, unsubstituted or 4-substituted by halogen; and X is —O—, —S—, —S(═O)—, —S(O 2 )—, —CH 2 —, —CF 2 — or —NH—.