The present invention relates to compounds of formula II wherein R1’is CH3； R1is CH3, ethyl, CF3, CH2OH, cyclopropyl or cyano, or R1’and R1may form together a 1,1-dioxo-tetrahydro-thiophen-3-yl ring； R2is hydrogen, CH3, ethyl, isopropyl, tert-butyl, cyclopropyl, cyclopropyl-methyl or hydroxy-methyl； R3is hydrogen, Cl, F, CF3, CH3, isopropyl, methoxy, cyano or cyclopropyl； R4is hydrogen, CH3, F or Cl； or to a pharmaceutically acceptable salt or acid addition salt, to a racemic mixture, or to its corresponding enantiomer and/or optical isomer and/or stereoisomer thereof. The compounds of formula I may be used in the treatment of psychiatric disorders such as schizophrenia, bipolar disorder, obsessive-compulsive disorder or autism spectrum disorder.本發明係關於式I化合物：I 其中 R1'為CH3； R1為CH3、乙基、CF3、CH2OH、環丙基或氰基，或 R1'與R1可一起形成1,1-二側氧基-四氫-噻吩-3-基環； R2為氫、CH3、乙基、異丙基、第三丁基、環丙基、環丙基-甲基或羥基-甲基； R3為氫、Cl、F、CF3、CH3、異丙基、甲氧基、氰基或環丙基； R4為氫、CH3、F或Cl； 或其醫藥上可接受之鹽或酸加成鹽、外消旋混合物或其相應對映異構體及/或光學異構體及/或立體異構體。 該式I化合物可用於治療精神病症，諸如精神分裂症、躁鬱症、強迫症或自閉症類群障礙。
