The present invention relates to compounds of formula I wherein Y is C-R1’； R1’ is hydrogen, F or Cl； R1 is F or Cl； R2 is hydrogen or lower alkyl； R3 is phenyl, pyridinyl or isothiazolyl, wherein the N atom in the pyridinyl group may be in different positions, optionally substituted by one or two halgen atoms； R4 is hydrogen or lower alkyl； Het is a 5-membered heteroaryl group, containg two or three heteroatoms, selected from N, O or S, optionally substituted by lower alkyl, cycloalkyl, lower alkoxyalkyl, heterocycloalkyl, wherein the hetero-atom is O, or lower alkyl substituted by hydroxy, or is a bicyclic heteroaromatic ring, containing two or three N-heteroatoms selected from the groups,,or；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 may be used for the treatment of Parkinson’s disease, anxiety, emesis, obsessive compulsive disorder, autism, neuroprotection, cancer, depression and diabetes type 2.本發明係關於式I化合物，其中Y係C-R1’；R1’係氫、F或Cl；R1係F或Cl；R2係氫或低碳烷基；R3係視情況由一個或兩個鹵素原子取代之苯基、吡啶基或異噻唑基，其中該吡啶基中之N原子可在不同位置；R4係氫或低碳烷基；Het係5員雜芳基，其含有兩個或三個選自N、O或S之雜原子，視情況由低碳烷基、環烷基、低碳烷氧基烷基、雜環烷基(其中該雜原子係O)或羥基取代之低碳烷基取代，或係選自以下基團之含有兩個或三個N-雜原子之二環雜芳香族環：、、或或其醫藥上可接受之鹽或酸加成鹽、外消旋混合物，或其相應鏡像異構物及/或光學異構物及/或立體異構物。該等化合物可用於治療帕金森氏病(Parkinson’s disease)、焦慮症、嘔吐、強迫症、自閉症、神經保護、癌症、抑鬱症及2型糖尿病。
