Glucose Positions Affect the Phloem Mobility of Glucose-fipronil Conjugates

In our previous work, a glucose-fipronil (GTF) conjugate at the C-1 position was synthesized via click chemistry and a glucose moiety converted a non-phloem-mobile insecticide fipronil into a moderately phloem-mobile insecticide. In the present paper, fipronil was introduced into the C-2, C-3, C-4, and C-6 positions of glucose via click chemistry to obtain four new conjugates and to evaluate the effects of the different glucose isomers on phloem mobility. The phloem mobility of the four new synthetic conjugates and GTF was tested using the Ricinus seedling system. The results confirmed that conjugation of glucose at different positions has a significant influence on the phloem mobility of GTF conjugates.