The Insecticidal Activity of Jasmolin II and Its Isolation from Pyrethrum (Chrysanthemum cinerariaefolium Vis.)1

The isolation and the insecticidal activity of jasmolin II, 4',5'-dihydropyrethnn II, a new constituent of pyrethrum ( Chrysanthemum cinerariaefolium Vis.) are described. Jasmolin II was nearly as toxic as cinerin II against Musca domestica L.; both were about ⅖ as toxic as a commercial pyrethrum extract. With a synergist, piperonyl butoxide [1 part insecticide to 8 parts synergist (w/w) ], jasmolin II was considerably less toxic than either pyrethrum extract or cinerin IL Jasmolin II was about 1/200 as toxic as pyrethrum extract against Tribolium castaneum Herbst, 1/17 as toxic against Aedes aegypti (L.), and Phasdon cochleariae (F.), about 1/14 as toxic against Daphnia magna Straus, and ¼ as toxic against Tenebrio molitor L.