Abstract:With vanillin, decanoic acid and sulfinyl chloride as initial material, capsaicinoid of N-( 4-hydroxy-3-methoxybenzyl )-decanoylamide was synthesized successfully by three synthesis procedures only. According to IR, 1HNMR, 13CNMR and elemental analysis data, its molecular structure was confirmed. Comparative research on physiological activity for natural capsaicinoid and target compound was made.And the experiment results on physiological activity were as follows: N-( 4-hydroxy-3-methoxybenzyl )-decanoylamide was similar to natural capsaicinoid in potency of pungency and the former was 0.4% smaller than the latter in pungency; the antinociceptive effect of target compound was stronger 30% than natural capsaicin; they were almost same and stronger than sodium benzoate in antibacterial activity; they were also similar as a repellent for mice. The target compound and natural capsaicinoid were both in the toxicity grade of 3 (low toxicity) As a conclusion, the synthetic capsaicinoid of N-( 4-hydroxy-3-methoxybenzyl )-decanoylamide had the value of replacing natural capsaicin in the above biological activity.