Predicting mosquito repellent potency of N,N-diethyl-m-toluamide (DEET) analogs from molecular electronic properties

Specific molecular electronic properties of 30 N,N-diethyl-m-toluamide (DEE T) analogs demonstrate functional dependence with their reported duration o f protection against mosquito bites, thus providing predictors of insect re pellent efficacy. No single electronic property is sufficient to predict re pellent efficacy as measured by protection time, rather a set of specific e lectronic properties is required. Thus, the values of the van der Waals sur face electrostatic potential by the amide nitrogen and oxygen atoms, the at omic charge at the amide nitrogen atom, and the dipole moment must all be i n optimal ranges for potent repellency. The electronic properties were calc ulated using the AM1 semi-empirical quantum chemical method using commercia l software. These easily calculable predictors of repellent efficacy should be useful in predicting the relative efficacy of newly designed compounds, thus guiding the selection of new repellents for testing.