Novel pyridine derivatives

A compound of formula (I)

• wherein
• A1 is —S— or —S(O)2—;
• A2 is nitrogen or —(CH)—;
• R1 is halogen or haloalkyl;
• R2 is hydrogen or halogen;
• R3 is hydrogen, halogen, haloalkyl, pyrazolyl, [1,2,3]-triazolyl or [1,2,4]-triazolyl;
• R4 and R6 are independently selected from hydrogen, alkyl, haloalkyl and halophenyl;
• and
• R5 is hydrogen, halogen, haloalkyl, alkoxy, haloalkoxy, alkylpyridinyl, halopyridinyl or alkylpyrazolyl;
• or a pharmaceutically acceptable salt thereof.