The present invention relates to a novel two cyclic cinnamide compound and a pharmaceutical agent comprising the compound as an active ingredient. The two cyclic cinnamide compound represented by the general formula (I): wherein represents a single bond or a double bond; Ar1 represents a phenyl group or pyridinyl group that may be substituted with 1 to 3 substituents; R1 and R2 each represent a C1-6 alkyl group, a hydroxyl group, or the like; Z1 represents a methylene group or vinylene group, which may be substituted with 1 or 2 substituents selected from Substituent Group A1, an oxygen atom, or an imino group that may be substituted with a substituent selected from Substituent Group A1; and p, q, and r each represent an integer of 0 to 2, which has an effect of reducing Aβ40 and Aβ42 production, and thus is particularly useful as a prophylactic or therapeutic agent for a neurodegenerative disease caused by Aβ such as Alzheimer's disease or Down's syndrome.