Patent ID: 6861430

Claim:
A compound of formula I wherein R 1 is a group of formula wherein R 6 is (C 1-4 )alkyl, R 7 and R 8 , independently, are hydrogen or (C 1-4 )alkyl and X is hydrogen, (C 1-4 )alkoxy, (C 1-4 )alkylamino or di(C 1-4 )alkylamino, R 2 and R 3 , independently, are (C 1-4 )alkoxy(C 1-4 )alkyl or (C 3-7 )cycloalkyl(C 1-4 )alkyl, or, provided R 1 is not an optionally substituted phenyl group, (C 1-12 )alkyl, R 4 is hydrogen, (C 1-4 )alkyl, (C 1-4 )alkoxy, halogen or trifluoromethyl and R 5 is hydrogen or (C 1-4 )alkyl, in free base or acid addition salt form.