The present invention relates to compounds of formulas IA and IBor 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 in 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IA及IB化合物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。