Etrimfos is a colorless liquid, mp 3.35 C, vp 6.5 mPa
(20 C). Solubility in water is 40 mg/L (23–24 C). It is
miscible with most organic solvents. Log Kow > 3.3. Neat
etrimfos is unstable and degrades ca. 40% in 28 d at
50 C, but the dilute solutions in nonpolar solvents and its
formulations are stable (about 5% loss in 1 y at ca. 20 C).
It is hydrolyzed in aqueous media; DT50 (25 C) at pH 3, 6,
and 9 are 0.4, 16, and 14 d, respectively.
Pure product is colorless oily liquid, m.p. -3.4℃, relative density 1.195 (20℃), refractive index n20D1.5068, can be mutually soluble with acetone, chloroform, methanol, ethanol, hexanol, dimethyl sulfoxide, xylene, solubility in water 10g/L, 25℃ hydrolysis half-life of 0.4d (pH=3), 16d (pH=6), 14d (pH=9). Ethylpyrimidine sulfide is unstable in pure form, but is stable in dilute solutions in nonpolar solvents for which suitable stabilizers have been reported.
Satisfar is a pesticide sprayed on plants and vegetables as insecticide to fend off pests.
Etrimfos is used to control chewing insects in top fruit, vines,
olives and a number of other crops. It is also used to control stem borers in
rice and insect and acarid pests of stored products.
Agricultural insecticide.
ChEBI: Etrimfos is an organic thiophosphate.
The commercial production of etrimfos typically starts with the preparation of the pyrimidine derivative, which is then reacted with dimethyl phosphorochloridothioate under controlled conditions to form the final phosphorothioate ester. The reaction is carried out in organic solvents such as acetone or ethanol, where etrimfos is fully miscible, and the product is purified through distillation or crystallisation to achieve the desired technical grade.
Contact and stomach action, non-systemic. Acetylcholinesterase (AChE) inhibitor.
Etrimfos is principally degraded in soil and plants via dearylation of
etrimfos itself or by hydrolysis of etrimfos oxon to the pyrimidinol
(6-ethoxy-4-hydroxy-2-ethylpyrimidine), further metabolism of which
involves de-ethylation to a dihydroxypyrimidine (2-ethyl-4,6-dihydroxypyrimidine).
In mammals both hydrolysis and demethylation to desmethyl
etrimfos are involved in detoxification. Additionally, the ethyl and
ethoxy groups of the pyrimidinol hydrolysis product may be hydroxylated
and conjugated. Etrimfos oxon is metabolically highly unstable and
is often not detected.
The acute oral LD50 for rats is 1,600–1,800 mg/kg.
Inhalation LC50 (1 h) for rats is >200 mg/L air. NOEL
(2 yr) for rats is 6 mg/kg diet (0.3 mg/kg/d). ADI is
3 μg/kg b.w. The principal degradation pathway in
mammals, plants, and soils is pyrimidinyl ester bond
cleavage: the major metabolites are 6-ethoxy-4-hydroxy-
2-ethylpyrimidine and its further transformed products.
Degradation in mammals involves demethylation to
desmethyl etrimfos. The DT50 in soils at pH 6.8 was
3–10 d.
Etrimfos is unstable when pure but dilute solutions in non-polar solvents
and formulations are stable. Half-lives in water at pH 3,6 and 9 were 0.4,
16 and 14 days, respectively. Etrimfos is stable to light (PM).
