ABSTRACT
Two methods including gas chromatography tandem mass spectrometry (GC-MS/MS) and high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) were established to detect common alkyl sulfonates and aryl sulfonates genotoxic impurities. Four alkyl sulfonates and methyl benzenesulfonate were determined by GC-MS/MS using butyl methanesulfonate as the internal standard, the chromatographic column was HP-5MS UI (30 mm × 0.25 mm, 0.25 µm), the carrier gas was helium, the flow rate was 1.0 mL·min-1 in a constant flow mode, the sample inlet temperature was set to 250 ℃, the split ratio was 10∶1, and the initial temperature of the heating program was 80 ℃, maintained for 1 minute, and then increased to 240 ℃ at a heating rate of 30 ℃·min-1 for 2 minutes. The mass spectrometry detector was an electron bombardment ion source (EI source), the data collection condition was multi reaction monitoring mode (MRM), and method validation using the raw material of clinical drug citalopram hydrobromide as a sample. The results showed that the linear range of four alkyl sulfonates and methyl benzenesulfonate were good at 3-50 ng·mL-1 and 9-150 ng·mL-1, with a correlation coefficient of r > 0.999, The spiked recovery was 80%-120%. The detection limits were 1 and 3 ng·mL-1; Ten aryl sulfonates determined by LC-MS/MS, the chromatographic column was CSH Fluoro phenyl (100 mm × 2.1 mm, 1.7 µm), the mobile phase was methanol (B)-5 mmol·L-1 ammonium formate (D), with a flow rate of 0.2 mL·min-1, and gradient elution was performed. The gradient program (T/% B) was set as 0/20, 25/90, 35/90, 42/20. The mass spectrometer detector was electro spray ionization with positive ionization mode (ESI+), the data collection was in dynamic multi reaction monitoring mode (dMRM), and the method was validated using the raw material of the clinical drug citalopram hydrobromide as a sample. The results showed that the linear range of aryl sulfonates were good at 9-2 000 ng·mL-1, 3-100 ng·mL-1 and 0.9-30 ng·mL-1, respectively. The correlation coefficient r > 0.999, the spiked recovery was 80%-120%. The detection limits were 30, 1 and 0.3 ng·mL-1. Two detection methods did not detect potential sulfonate genotoxicity impurities in the above APIs. The established analytical methods are reliable and effective, which can provide reference for drug quality control and detection.
ABSTRACT
To explore insecticides targeting the γ-aminobutyric acid (GABA) receptor, two series of novel isoxazoline derivatives containing sulfonic and carboxylic esters were designed and synthesized. Their insecticidal activities against Plutella xylostella, Mythimna separata, and Aedes aegypti larvae and their structure-activity relationship were investigated. The sulfonate-containing isoxazoline derivatives (10k-q) exhibited promising insecticidal activities against the three insect larvae. Compound 10o displayed excellent activities with LC50 values of 8.32, 5.23, and 0.35 µg/mL at 48 h against P. xylostella, M. separata, and A. aegypti larvae, respectively, which were better than or similar to those of avermectin. Furthermore, compound 10o exhibited a faster insecticidal effect than avermectin against M. separata. The mode of action of 10o was preliminarily verified by molecular docking, theoretical calculations, and measurement of glutamate decarboxylase and glutamic pyruvic transaminase activities. Compound 10o is a novel insecticidal candidate acting on GABA receptors, which could guide the discovery of isoxazoline insecticides.
