Qi-Bo Li,Min Liao,Qing Liu,Tong Feng,Zhi-Yuan Xu,Chang-Hui Rui,Shang-Zhong Liu
New 1,3,5-trimethylpyrazole-containing malonamide derivatives based on pyflubumide were designed, synthesized, and characterized using1H-NMR,13C-NMR, and high-resolution mass spectra (HRMS). The results of preliminary bioassays showed that the target compounds possessed good activities againstTetranychus cinnabarinus,Plutella xylostella, andAphis craccivora. Most of the target compounds exhibited moderate to good acaricidal activity againstTetranychus cinnabarinusat a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds8mand8pexhibited 70.0% mortality. In addition, some of the target compounds exhibited good insecticidal activities againstPlutella xylostellaat a concentration of 200 µg/mL, especially compounds8iand8o,which achieved 100.0% mortality at a concentration of 100 µg/mL. Interestingly, some of the target compounds exhibited potent anti-aphid activity againstAphis craccivoraat a concentration of 200 µg/mL; furthermore, compounds8pand8qdemonstrated 100.0% anti-aphid activity at a concentration of 50 µg/mL. The preliminary analyses of the structure–activity relationships (SAR) indicated that the acaricidal and insecticidal activities varied significantly depending on the type of substituent and substitution pattern, which provides guidance for the further investigation of such structural modifications.Keywords:malonamide;pyflubumide;synthesis;acaricidal and insecticidal activities
Mengnan Li,Jinling Wang,Xiaoyong Xu,Guobin Ren,Bin Zhu,Minghuang Hong,Zhong Li
Cycloxaprid (CYC) is a potentially commercially available pesticide with high activity, but its further development is limited due to the poor solubility and stability. In this paper, the co-crystallization strategy is applied to improve the physical and chemical properties of CYC for the first time. The cycloxaprid-succinimide (CYC–SM) co-crystal and the cycloxaprid-trifluoromethanesulfonamide (CYC–TS) co-crystal with a stoichiometric ratio of 1:1 between API and co-crystal former were successfully prepared through experimental screening and systemically characterized by powder X-ray diffraction, nuclear magnetic resonance, differential scanning calorimetry, thermogravimetry, Fourier transform infrared spectroscopy, and single-crystal X-ray diffraction techniques. The weak interaction of CYC–SM and CYC–TS co-crystals was quantified and analyzed by quantum chemistry calculations. Compared with CYC–TS, the molecular orbital and lattice energy calculation results of CYC–SM show lower chemical reactivity and better stability, which is consistent with the results of solid-state and solution stability tests. The partially weak interaction remained in the solution, and the weakly basic nature of SM and the relatively slow release of CYC from CYC–SM contributed to the promoted solution stability of CYC–SM. In addition, due to the introduction of SM molecules, the solubility of CYC–SM was significantly improved. The CYC–SM co-crystal could be a candidate solid-state form that provides an opportunity for the further development of CYC.
危险品化学品经营许可证（带存储）