Azacycloalkane derivatives of structural formula I are selective inhibitors of stearoyl-coenzyme A delta-9 desaturase (SCD1) relative to other known stearoyl-coenzyme A desaturases. The compounds of the present invention are useful for the prevention and treatment of conditions related to abnormal lipid synthesis and metabolism, including cardiovascular disease, such as atherosclerosis； obesity； diabetes； neurological disease； metabolic syndrome； insulin resistance； and liver steatosis.
