Synthesis and morphogenetic activity of derivatives and analogs of aryl geranyl ether juvenoids

1-(4′-Ethylphenoxy) -3,7-dimethyl-6,7-epoxy-trans-2-octene (the ethyl epoxide juvenoid) and its nonepoxidized intermediate (the ethyldiene) were used to prepare compounds involving 34 modifications of the geranyl moiety including 13 mono-and bicyclic derivatives. Mechanisms are proposed for tetrahydrofurandiol formation on oxidative cyclization of the ethyldiene, ethyl epoxide, and their 6,7-diol derivative. Additional syntheses yielded analogs involving 17 modifications in the aryl moiety. The ethyl epoxide is more active in the Tenebrio molitor juvenoid assay than any of its chemical degradation products. Some 7-alkoxide derivatives are more potent than the ethyl epoxide in Tenebrio assays but they are less active in the ecdysone-stimulated Drosophila imaginal disk evagination assay. High potency in the Tenebrio test may depend, in part, on structural features appropriate to enter a pool or combine with a site in the insect where the juvenoid is refractory to degradation.