Patent ID: 8084463

Claim:
A compound of formula I in pharmaceutically acceptable salt form wherein R 1 and R 2 are each independently phenyl, one or both of R 1 and R 2 being substituted at one position by halo, C 1 -C 4 -alkyl or C 1 -C 4 -alkoxy, and R 3 is hydroxy; or R 1 and R 2 are each unsubstituted phenyl, and R 3 is hydrogen, C 1 -C 4 -alkyl or C 1 -C 4 -alkoxy; or R 1 is C 3 -C 6 -cycloalkyl, and R 2 is phenyl, thiophenyl or furanyl, and R 3 is hydroxy; and R 4 is C 1 -C 4 -alkyl substituted at one, two or three positions by; —CO—NHR 6 where R 6 is a isoxazolyl optionally substituted by phenyl, or R 6 is pyrazinyl or pyrimidinyl.