The present invention provides compounds of Formula I for the treatment of neurodegenerative or cognitive diseases. The method further provides for piperidine-2-one and piperidine-2-thione intermediates to compounds of formula I.本發明提供了具有式I之化合物用於治療神經退行性或認知疾病。該方法進一步提供了具有式I之化合物之哌啶-2-酮以及哌啶-2-硫酮中間體。