Disclosed herein is a composition having activity of inhibiting acyl-CoA:
cholesterol acyltransf erase, which comprises retrofractamide A,
pipercide, piperrolein B, piperchabamide D, pellitorin or combinations
thereof, or a pharmaceutically acceptable salt thereof . The composition
is effective for preventing and treating vascular diseases, such as
hyperlipidemia, arteriosclerosis, etc.