piperidines and (2-hydroxymethylcyclohexyl)acetic-acid-lactone

Four repellents, N,N-diethyl-3-methyl-benzamide (deet), 2-hydroxy-methyl-cyclohexyl acetic acid lactone (CIC-4), and 2 piperidines (1-[3-cyclohexen-1-ylcarbonyl] piperidine [AI3-35765] and 1-[3-cyclohexen-1-ylcarbonyl]-2-methylpiperidine [AI3-37220]) were evaluated alone and in combination against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus using a modified in vitro test system. This method was a valuable tool for comparing effective concentrations of the new compounds. Because of the controlled conditions of the test, it was possible to use the results of assays that had been conducted over a 5-year period and to perform the many replications necessary to evaluate combinations of compounds. The new candidate repellents were generally as effective as deet. Although speculative at this time, there was some evidence of synergistic interaction. Repellent combinations of CIC-4/AI3-37220/AI3-35767, deet/AI3-35765, and deet/AI3-37220/AI3-35765 against An. stephensi and CIC-4/AI3-35765, deet/AI3-37220/AI3-35765, AI3-37220/AI3-35765, and CIC-4/AI3-37220 against Ae. aegypti were more effective than the component compounds alone.

Topics: Aedes; Animals; Anopheles; Chromones; Culex; DEET; Evaluation Studies as Topic; Female; Insect Repellents; Mosquito Control; Piperidines

The repellents diethylmethylbenzamide (deet), (2-hydroxymethylcyclohexyl) acetic acid lactone (CIC-4), and 1-(3-cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220) were compared for their effectiveness in protecting 5 soldiers against the bites of Anopheles spp. at a village in Papua New Guinea. All 3 repellents, applied as 25% ethanol concentrations, provided > or = 95% protection against primarily An. farauti 4 for at least 3 h after application.

Topics: Animals; Anopheles; Chromones; DEET; Evaluation Studies as Topic; Humans; Insect Repellents; Mosquito Control; Papua New Guinea; Piperidines

Laboratory and field tests of the repellents diethyl methylbenzamide (deet), 1-(3-cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220), and (2-hydroxymethylcyclohexyl) acetic acid lactone (CIC-4) were conducted against Anopheles farauti s.s. Laveran, an important malaria vector in the southwest Pacific region. In the laboratory, An. farauti was tolerant of all 3 repellents, but deet and CIC-4 provided significantly better protection than AI3-37220. The field study was conducted in rain forest located near Innisfail, northern Queensland, and tested 25% (vol:vol) ethanol solutions of each repellent against An. farauti. All 3 repellents provided > 95% protection against An. farauti for 5 h after application. In contrast to the laboratory tests, protection provided by AI3-37220 was significantly better than that by either deet or CIC-4, and there was no difference between protection by deet and CIC-4. The protection by deet and CIC-4 declined 8 h after application and provided < or = 50% protection at 9 h. In contrast, AI3-37220 provided > or = 94% protection for 9 h.

Topics: Animals; Animals, Laboratory; Animals, Wild; Anopheles; Australia; Chromones; DEET; Female; Forearm; Humans; Insect Repellents; Male; Piperidines; Skin

Laboratory and field tests of the repellents diethyl methylbenzamide (deet), 1-(3-Cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220), and (2-hydroxymethylcyclohexyl) acetic acid lactone (CIC-4) were conducted against Anopheles dirus Peyton & Harrison, the principal malaria vector in Thailand. In the laboratory, An. dirus was more sensitive to CIC-4 than either AI3-37220 or deet. The duration of protection provided by each repellent in laboratory tests increased with higher concentrations of repellents and when exposed in cages containing fewer mosquitoes. A field study in Chanthaburi Province, southeastern Thailand, during November 1993 tested 25% (wt:wt) ethanol solutions of each repellent against An. dirus. In contrast to the laboratory experiments, protection provided by AI3-37220 was significantly better than either deet or CIC-4 and there was no significant difference between deet and CIC-4. Protection provided by deet and CIC-4 fell to below 95% 2 h after repellent application, whereas AI3-37220 provided > 95% protection for 4 h. The protection provided by all repellents fell to < or = 65% 7 h after repellent application.

Topics: Aedes; Animals; Anopheles; Chromones; DEET; Female; Humans; Insect Repellents; Mosquito Control; Piperidines; Thailand

Four repellents, deet, AI3-37220, AI3-35765, and CIC-4, prepared as 12.5% ethanol solutions, were evaluated against biting midges on Stansbury Islands, UT. Leptoconops americanus Carter was the only species that was biting human volunteers during the study. This species bit primarily on the ears at rates up to 840 bites per hour. All four repellents significantly reduced the number of bites on treated volunteers. AI3-37220 consistently provided the longest period of protection, giving 97 and 74% protection at 4 and 8 h, respectively. In a direct statistical comparison, AI3-37220 significantly outperformed deet. CIC-4 and AI3-35765 were the least effective repellents, providing 45-47% protection 8 h after application.

Topics: Animals; Ceratopogonidae; Chromones; DEET; Insect Control; Insect Repellents; Piperidines; Utah

Deet, the lactone CIC-4, and the piperidine compounds A13-37220 and A13-35765 were evaluated for initial repellency against laboratory-reared Anopheles albimanus Wiedemann, An. freeborni Aitken, An. gambiae Giles, An. stephensi Liston, and Phlebotomus papatasi (Scopoli) using a dose-response testing procedure on human volunteers. In addition, deet and CIC-4 were tested against Lutzomyia longipalpis (Lutz & Neiva). In general, the repellency of A13-37220, A13-35765, and CIC-4 was not markedly different from that of deet against each species tested; however, the different species varied greatly in response to the repellents. Overall, An. stephensi, L. longipalpis, and P. papatasi were the most sensitive, and An. albimanus the most tolerant species. The four repellents subsequently were tested against An. stephensi and An. albimanus to determine the duration of repellency. AI3-37220 provided effective (> 90%) protection against An. stephensi bites for 7 h, whereas deet, AI3-35765, and CIC-4 provided 6, 5, and 3 h of protection, respectively. Each of the four compounds provided < 1 h of protection against An. albimanus bites.

Topics: Animals; Anopheles; Chromones; DEET; Female; Humans; Insect Bites and Stings; Insect Repellents; Lethal Dose 50; Male; Piperidines; Psychodidae

Deet (N,N-diethyl-3-methyl-benzamide), the lactone CIC-4 ([2-hydroxy-methyl-cyclohexyl] acetic acid lactone), the USDA Proprietary Chemicals AI3-37220 (1- [3-cyclohexen-1-ylcarbonyl]-2-methylpiperidine) and ++[3-35765 (1-[3-cyclohexen-1-ylcarbonyl] piperidine), and the U.S. military extended duration repellent formulation (EDRF) of deet were evaluated for repellency in the laboratory and field against the black flies Prosimulium mixtum and P. fuscum. CIC-4, AI3-37220, and AI3-35765 were as effective as deet at repelling P. mixtum and P. fuscum in laboratory and field experiments. Only the EDRF provided significantly longer protection than the deet standard against these black flies in the field.

Topics: Animals; Chromones; DEET; Female; Humans; Insect Bites and Stings; Insect Repellents; Piperidines; Simuliidae