Synthesis of seven sinapine analogs and their effects on the tension of smooth muscle of intestines isolated from rabbit

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.