Patent ID: 7425551

Claim:
A compound of formula I wherein A 1 is —CHR— or —C(O)—; A 2 is —C(O)— and R 2 and R 3 are each independently hydrogen, lower alkyl, halogen, hydroxy or lower alkoxy; or A 2 is —O—C(O)— and R 2 and R 3 are each independently hydrogen or lower alkyl; R is hydrogen or lower alkyl substituted by halogen; R 1 is hydrogen, or is lower alkyl or —(CH 2 ) n -aryl, each of which is optionally substituted by halogen; R 4 is lower alkyl substituted by halogen; and n is 0, 1 or 2; or a pharmaceutically acceptable acid addition salt, optically pure enantiomer, racemate or diastereomeric mixture thereof.