Novel azetidine derivatives

A compound of formula (I)

• wherein
• one of A1 and A2 is —NR9— and the other one is —CH2—;
• R1 is halogen;
• R2 is hydrogen, halogen, alkyl or haloalkyl;
• R3 is hydrogen, halogen, alkyl or haloalkyl;
• R4 and R5 are both hydrogen at the same time;
• or R4 and R5 together with the carbon atom to which they are attached form cycloalkyl;
• R6 is hydrogen, halogen, alkyl, haloalkyl or cycloalkyl;
• R7 is hydrogen, halogen, alkyl, haloalkyl or cycloalkyl;
• R8 is hydrogen, alkyl, haloalkyl, alkoxy, haloalkoxy, cycloalkyl, alkylpyrdinyl, alkyl-1H-pyrazolyl, phenyl, substituted phenyl, heterocyclyl or substituted heterocyclyl, wherein heterocyclyl is pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, pyrrolyl, pyrazolyl, imidazolyl, triazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiophenyl, thiazolyl, thiadiazolyl, piperidinyl, piperazinyl, pyrrolidinyl or morpholinyl, wherein substituted phenyl is phenyl substituted with one to three substituents independently selected from alkyl, halogen, cycloalkyl, haloalkyl, alkoxy, haloalkoxy, halocycloalkyl and nitrile and wherein substituted heterocyclyl is heterocyclyl substituted with one to three substituents independently selected from alkyl, halogen, cycloalkyl, haloalkyl, alkoxy, haloalkoxy, halocycloalkyl and nitrile;
• and
• R9 is hydrogen, alkyl, haloalkyl, cycloalkyl, acyl or alkoxycarbonyl;
• or a pharmaceutically acceptable salt or ester thereof.