Synthesis and analysis of radioisotope carbon-14 labelled chlorantraniliprole

Two versions of radioisotope carbon-14 labelled chlorantraniliprole, 3-bromo-N-(4-chloro-2-methyl-6-(methylcarbonyl-¹⁴Ccarbamoyl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide ( 2 , 55.6 mCi, radiochemical purity 99.8%, chemical purity 99.1%, specific activity 52.45 mCi/mmol) and 3-bromo-N-(4-chloro-2-methyl-6-(methylcarbamoyl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carbonyl-¹⁴Ccarboxamide ( 3 , 58.6 mCi, radiochemical purity 99.6%, chemical purity 98.4%, specific activity 52.30 mCi/mmol), were synthesized from barium ¹⁴Ccarbonate via eight-step radioactive reactions including Grignard reaction, nucleophilic substitution, amination reaction, condensation, and etc. Pure C-14 labelled products were obtained after RP-HPLC purification in the overall radiochemical yield of 32% and 52%, respectively. The products were characterized by ESI-MS, ¹H NMR and HPLC-FSA. Their technical data was determined by TLC-IIA, HPLC-LSC, HPLC-FSA/PDA/MS and LSC, respectively. These products could be used as radiotracers and meet the requirement of the study on the metabolism of chlorantraniliprole for registration in China.