Capsaicinol: Synthesis by Allylic Oxidation and Its Effect on TRPV1-Expressing Cells and Adrenaline Secretion in Rats
作者:Kenji KOBATA、Takahito IWASAWA、Yusaku IWASAKI、Akihito MORITA、Yuichi SUZUKI、Hiroe KIKUZAKI、Nobuji NAKATANI、Tatsuo WATANABE
DOI:10.1271/bbb.60064
日期:2006.8.23
Capsaicinol is an ingredient of hot red pepper. In this study, we developed a novel method for capsaicinol synthesis and examined capsaicinol’s physiological effects on capsaicin receptor (TRPV1)-related actions. Allylic oxidation of capsaicin by palladium acetate (Pd(OAc)2) resulted in the formation of (±)-capsaicinol acetate at a 7.2% yield in a single step. The effectiveness of (±)-capsaicinol in TRPV1 activation (EC50=1.1 μM) was found to be weaker than that of capsaicin (EC50=0.017 μM), whereas the efficacy of (±)-capsaicinol reached 75% of that of capsaicin. Intravenous administration of (±)-capsaicinol in anesthetized rats dose-dependently enhanced adrenaline secretion from the adrenal gland. The response to a 5 mg/kg-dose of (±)-capsaicinol was comparable to that of a 0.05 mg/kg-dose of capsaicin. The relative pungency of capsaicinol to capsaicin was coincident with the relative effectiveness in inducing these TRPV1-related actions.
辣椒素醇是辣椒的一种成分。在这项研究中,我们开发了一种合成辣椒素醇的新方法,并研究了辣椒素醇对辣椒素受体(TRPV1)相关作用的生理效应。通过醋酸钯(Pd(OAc)2)对辣椒素进行烯丙基氧化,可生成(±)-辣椒素醇醋酸酯,单步产率为 7.2%。研究发现,(±)-辣椒素醇激活 TRPV1 的效力(EC50=1.1 μM)弱于辣椒素(EC50=0.017 μM),而(±)-辣椒素醇的效力则达到辣椒素的 75%。麻醉大鼠静脉注射(±)-辣椒素醇可剂量依赖性地促进肾上腺分泌肾上腺素。5 毫克/千克剂量的(±)-辣椒素醇的反应与 0.05 毫克/千克剂量的辣椒素的反应相当。与辣椒素相比,辣椒素醇的辛辣程度与诱导这些 TRPV1 相关作用的相对有效性一致。