The present invention is directed to phenylcyanoquinolinone compounds which may be useful as therapeutic agents for the treatment of central nervous system disorders associated with phosphodiesterase 9 (PDE9). The present invention also relates to the use of such compounds for treating neurological and psychiatric disorders, such as schizophrenia, psychosis or Huntingtons disease, and those associated with striatal hypofunction or basal ganglia dysfunction.
