Seven sinapine analogs (6a-6g) were synthesized using cinnamon acid or benzoic acid and their derivatives as starting materials, which obtained from substituted benzaldehyde and malonate. The structures of target compounds were characterized by IR, 1H NMR and elemental analysis. The effects of compounds 6a-6g on the smooth muscle of intestine isolated from rabbit were studied, and the experimental results showed that compounds 6a, 6d and 6g had diastolic action, while 6f had contractile action.