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Attraction of Popillia japonica Newman to 15 substituted phenethyl acetates and 20 related acetates, each in combination with eugenol as 7:3 mixtures, was compared with attraction to the standard lure, phenethyl propionate + eugenol (7:3). The most active lure, o -nitro-phenethyl acetate + eugenol, was 60% as active as the standard. However, when 4 chemicals found in apple essences and 7 homologues of 2 of these chemicals were added to the standard lure, 1 additive, heptyl 2-melhyl-butyrate, increased activity 30%.

Sixty compounds, comprising a large variety of structures, were tested in the laboratory for juvenile hormone (HI) activity against the pests Lygus lineolaris (Palisot de Beauvois), A phis gossypii Glover, Tetranychus cinnabarinus (Boisduval), and beneficial predators Chrysopa carnea Stephens, Geocoris punctipes (Say), Hippodamia convergens Geerin-Meneville that are associated with cotton. Against L. lincolaris, some compounds-particularly those with an unsaturated arylterpenoid structure-evoked a significant JH response. However, the activity was relatively low, and compounds that affected this species also had a deleterious effect on some of the beneficial species. The JH analogue ZR-512 had sufficient activity against A. gossypii to merit additional investigation, but none affected T. cinnabarinus except at extremely high doses.

The highly active juvenile hormone mimic JH-25 (7-ethoxy-1. ( P -ethylphenoxy)-3,7-dimethyl-2-octene) was incorporated into bleached flour at rates of 1 to 5 ppm, and the flour was then aged. No normal adults emerged from samples of the flour exposed periodically to Tribolium castaneum (Herbst) throughout the 400-day test. Chemical analyses of an extract of the flour by liquid chromatography with UV detection and bioassays of the extract against Tenebrio molitor L. showed that ca. ½ the JH-25 remained in the flour spiked with 1 ppm JH-25 after aging 1 year.

Commercial samples of deet, N, N -diethyl- m -toluamide, which usually contain varying amounts of the ortho and para isomers, can be analyzed rapidly by gas chromatography on a glass column containing 0.2% SP-1000 on 60/80 mesh Carbopak A, a graphitized carbon black. The normally difficult to resolve meta and para isomers are separated easily, and the isomers are determined quantitatively either by normalization or by utilization of an internal standard (acenaphithene). The isomeric contents of mixtures of known composition were readily determined to within 1% of the known absolute values.

Three alkanesulfonamides derived from nitrogen-containing heterocyclics showed promise as repellents vs. the yellowfever mosquito, Aedes aegypti (L.), when they were tested on clothing. In skin tests vs. A. aegypti with 20–25% ethanolic solutions, 1 of the 3, 1-(butylsulfonyl)pyrrolidine, was as effective as the standard, deet. Against German cockroach, Blattella germanica (L.), 1-(butylsulfonyl) piperidine gave 97–100% protection for at least 14 days.

Juvenile hormone activity of 42 mixed ethers containing an aromatic and a terpenoid moiety was compared with that of four 3,4-(methylenedioxy) phenyl analogues against the large milkweed bug, Oncopeltus fasciatus (Dallas), and the yellow mealworm, Tenebrio molitor L. Wide differences in activity between the 2 species were observed for the compounds with 17 different aromatic substituents. Several ethers were more active than their 3,4-(methylenedioxy) phenyl analogues.

Fifty-five analogues of disparlure, the sex attractant of Porthetria dispar (L.), were synthesized and tested at 2 levels of concentration in the field vs. disparlure for attraction of male gypsy moths. Most of the analogues were ineffective; the best of these, which were 40- to 100-fold less active than disparlure, were those most closely related to disparlure in structure. The data may aid in deciphering the mechanism of odor reception.