To cope with the global food shortage and insect pest, there is
an urgent need to discover new pesticides with novel modes of actions.
Ryanodine receptor (RyR) insecticides showed great promise in integrated
pest management. Herein, we report the synthesis of novel anthranilic
diamide derivatives incorporating pyrrole moieties targeting at insect
RyRs. The structures were confirmed by 1H NMR, 13C NMR, 19F NMR, and high-resolution mass spectrometry.
The preliminary bioassay results indicated that most of the title
compounds showed good to excellent insecticidal activities against
the oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella). For the oriental armyworm, Ij displayed the same
level of larvicidal activity as the positive control chlorantraniliprole,
with an LC50 value of 0.21 mg/L. For the diamondback moth, In, Io, Ip, and Iq exhibited
higher insecticidal activities than chlorantraniliprole. In particular, In had 50% larvicidal activity at 0.00001 mg/L. The calcium
imaging technique was applied to study the effect of Ij, In, and Ip on the intracellular calcium
ion concentration ([Ca2+]i) in central neurons
isolated from the oriental armyworm. The results indicated that the
tested compounds, such as chlorantraniliprole, could activate the
insect RyRs. Furthermore, comparative molecular field analysis and
density functional theory calculations were carried out to study the
structure–activity relationship.