Phosdiphen

The Uses of Phosdiphen

Phosdiphen is used specifically for the control of rice blast diseases (Pyricularia oryzae).

Definition

ChEBI: Phosdiphen is a dichlorobenzene.

Metabolic pathway

Limited information is available in the open literature to describe the degradation and metabolic fate of phosdiphen. Information presented in this summary is abstracted from an unpublished report provided by Mitsui Chemical Industry, 1979). Hydrolytic cleavage of the P-O ester linkages is the primary degradation pathway of phosdiphen in soil, plants and animals (Scheme 1). The cleavage product, dichlorophenol, was recovered as both free and conjugated metabolites.

Degradation

Phosdiphen (1) is stable in acidic solution and hydrolysed under alkaline conditions at 25 °C with DT₅₀ values of 4 days (pH 9) to 7 days (pH 7) (PM). Phosdiphen labelled in both rings degraded rapidly in rice paddy water with DT₅₀ values of 1-3 days. 2,4-Dichlorophenol(2) was the major product detected.