Short-efficient non-stereospecific syntheses of methyl cis-10,11-epoxy-7-ethyl-3,11-dimethyltrideca-trans-2,trans-6-dienoate (Ia) and methyl cis-10,11-epoxy-3,7,11-trimethyltrideca-trans-2,trans-6-dienoate (Ib), the Cecropia-derived insect juvenile hormones, are described. The pathways elaborated permit separation of isomers en route and thereby provide synthetic approaches to both the pure hormones and their biologically active isomers.