Synthesis of a Physiologically Active Compound of the Pellitorine Structure

Abstract

PELLITORINE, isolated from the roots of pellitory, Anacyclus pyrethrum, has aroused renewed interest since it has been shown to possess insecticidal activity. It has been stated by Jacobson¹ to possess a 'knockdown value' against house-flies equal to, and a toxicity somewhat more than half, that of the pyrethrins tested at the same concentration. Pellitorine (m.p. 72°) was shown by Gulland and Hopton² to be the isobutylamide of a n-nonadiene-1-carboxylic acid, and Jacobson¹ has since located the two double bonds in the 1 : 2 and 5 : 6 positions. Very recently, Raphael and Sondheimer³ have reported the synthesis of a liquid geometrical isomer of pellitorine, the cis-cis; while Jacobson⁴ has prepared another geometrical isomer (m.p. 54—55°) of unspecified configuration. Neither of these isomers possesses the pungency and the sialogogue characteristic of natural pellitorine and that of Jacobson is non-toxic to house-flies. These reports prompt us to describe briefly our own progress in this field.