Cyclic Acetals as Novel Long-Lasting Mosquito Repellents

Abstract

The use of skin repellents against hematophagous mosquitoes is an important personal protection practice wherever these insects are abundant and where they are vectors of diseases. DEET and Icaridin are the major synthetic insect repellents in commercial formulations and are considered the most effective. Here, we tested against the mosquito Aedes albopictus several cyclic hydroxyacetals synthesized by acetalization of commercially available aliphatic carbonyl compounds (ranging from C3 to C15) with either glycerol, 1,1,1-trismethyloletane, or 1,1,1-trismethylolpropane and compared their efficacy with commercial repellents. We found that several hydroxyacetals were comparable with DEET and Icaridin both in terms of the required dose and repellence duration, while a few performed better. For those most active, toxicity was investigated, finding that a few of them were less cytotoxic than DEET and less prone to permeate through cell layers. Therefore, such results indicate that novel safe mosquito repellents could be developed among cyclic hydroxyacetals.

Structure–Activity Relationship (SAR) Modeling of Mosquito Repellents: Deciphering the Importance of the 1-Octanol/Water Partition Coefficient on the Prediction Results

“…Analysis of the literature shows that lipophilicity is a physicochemical property that is found to be more or less important [14,24,[57][58][59][60] for describing and modeling the biting deterrence or repellent activity of molecules against mosquitoes. This difference is easily explainable because these studies always involve a very small number of molecules showing specific structural or functional characteristics.…”

Chemical Ecology and Management of Dengue Vectors

“…Plants identified as repellent for mosquitoes in chemical ecology studies are scarce. Most studies report the screening of plant essential oils, obtained by hydrodistillation, whose formulations are compared with the protection times found for the synthetic mosquito repellent DEET (N, N-diethyl-m-toluamide) (65,73). Despite DEET not being a semiochemical, its repellency has been shown to be olfactory based (122).…”