Syntheses in the Homologous Series of Capsaicin

Part I. Syntheses of N-(4-hydroxy-3-methoxybenzyl)-3, 7-dimethyl-octanamide and N-(4-hydroxy-3-methoxybenzyl)-nonanamide

Abstract

A new pungent compound, vanillyl 3, 7-dimethyloctanoylamide, has been synthesized by the condensation of vanillylamine with 3, 7-dimethyloctanoic acid which obtained from the catalytic hydrogenation followed by oxidation of geraniol occured more widely distributed in nature. The synthesis of another title compound is also reported. The pungency of these compounds was examined and compared with natural capsaicin mixture by panel test, and the result was shown as follows: vanillyl 3, 7-dimethyloctanoylamide > vanillyl n-nonylamide > natural capsaicin mixture. As the skin irritating effect, vanillyl 3, 7-dimethyloctanoylamide shows approximately one half the irritating action of vanillyl n-nonoylamide.