New insights on the molecular features and electrophysiological properties of dinotefuran, imidacloprid and acetamiprid neonicotinoid insecticides

Molecular features and toxicological properties of four common pesticides, acetamiprid, deltamethrin, chlorpyriphos and fipronil

“…This result is in agreement with the importance of electron delocalization characteristic of the push-pull fragment of neonicotinoids that we have pointed out in a recent study and with the expected increase of electron density (and consequently of hydrogen-bond basicity) of the pulling group. 10,53 This preference of the nitrile nitrogen with respect to the pyridinic nitrogen is also in line with the decrease of electron density of the Nsp 2 atom induced by the electronwithdrawing effect of the chlorine atom.…”

“…We previously investigated in details the structural features of this neonicotinoid at the DFT level with the MPWB1K functional. 10 Since the more recent metahybrid M06-2X functional is now recommended for applications involving kinetic properties and non-covalent interactions, 18 we have re-examined the structural properties of ACE at this level of theory and completed the previous results by taking into account the influence of water surroundings. In the case of ACE (Figure 1), three dihedral angles have been identified as degrees of freedom: D1(C10-C6-C5-N2); D2(C6-C5-N2-C2) and D3(C5-N2-C2-N1).…”

“…9 In this context, quantum chemical studies, structural bioinformatics and molecular modelling methodologies (docking, 3D-QSAR, molecular dynamic simulations) have appeared as promising and complementary tools. The first allows quantifying accurately relevant properties of insecticides, [10][11][12][13] the second gives the possibility of building the protein targets through homology modelling and the last provides detailed (static or dynamic) pictures of the insecticides-receptor interactions. [14][15][16] In this paper, we investigate, through Density Functional Theory calculations, the structural features and some physicochemical properties of four common pesticides belonging to different chemical classes, namely acetamiprid (ACE, neonicotinoid), chlorpyriphos (CHL, organophosphate), deltamethrin (DEL, pyrethroid) and fipronil (FIP, phenylpyrazole) ( Figure 1).…”

“…The pioneering works of Murray and Politzer,[22][23][24][25] pointed out the interest of molecular electrostatic potential descriptors for the prediction and analyses of the interaction sites of organic molecules. Since that, it has been consistently demonstrated that non-covalent molecular interaction properties, in particular hydrogen-bond properties, and electrostatic potential based descriptors are well correlated, owing to the main electrostatic character of the hydrogen-bond interaction 10,[26][27][28][29]. In the current work, we have analysed the absolute minimum values of the electrostatic potential, V min , located on each hydrogen-bond acceptor site, its use being recommended in many studies instead of the computed values on the molecular surface (V s,min ) for investigations dedicated to hydrogen-bond basicity properties [29][30][31][32][33][34].…”

The Differential Effect of Low-Dose Mixtures of Four Pesticides on the Pea Aphid Acyrthosiphon pisum

“…Insecticide groups include the IRAC groups, pyrethroids (3A), neonicotinoids (4A), organophosphates (1B), and fiproles (2B) [5]. Pyrethroids like deltamethrin (DEL) kill insects by acting on sodium channels [6], and neonicotinoids like acetamiprid (ACE) act as agonists of the nicotinic acetylcholine receptors [7,8], whereas organophosphates like chlorpyrifos (CHL) inhibit the action of the acetylcholinesterase, resulting in increased acetylcholine concentrations at the synapses [9,10]. More recent compounds like the phenylpyrazol fipronil (FIP) act as agonists of the insect RDL GABA receptors [11,12].…”