Diethyl phosphorothioic acid

Diazinon is rapidly biotransformed and excreted in mammals. Estimated half-times of diazinon persistence were 6 to 12 h in rats (Anonymous 1972) and dogs (Iverson et al. 1975). Most of the diazinon metabolites were excreted in the urine as diethyl phosphoric add and diethyl phosphorothioic acid in dogs (Iverson et al. 1975), and as hydroxy diazinon and dehydrodiazinon in sheep (Machin et al. 1974). 

The hydrolysis half-life in three different natural waters was approximately 48 d at 25 °C (Macalady and Wolfe, 1985). At 25 °C, the hydrolysis half-lives were 120 d at pH 6.1 and 53 d at pH 7.4. At pH 7.4 and 37.5 °C, the hydrolysis half-life was 13 d (Freed et al, 1979). At 25 °C and a pH range of 1-7, the hydrolysis half-life was about 78 d (Macalady and Wolfe, 1983). However, the alkaline hydrolysis rate of chlorpyrifos in the sediment-sorbed phase were found to be considerably slower (Macalady and Wolfe, 1985). In the pH range of 9-13, 3,5,6-trichloro-2-pyridinol and 0,0-diethyl phosphorothioic acid formed as major hydrolysis products (Macalady and Wolfe, 1983). The hydrolysis half-lives of chlorpyrifos in a sterile 1% ethanoFwater solution at 25 °C and pH values of 4.5, 5.0, 6.0, 7.0, and 8.0 were 11, 11, 7.0, 4.2, and 2.7 wk, respectively (Chapman and Cole, 1982). 

Photolytlc. Malathion absorbs UV light at wavelengths more than 290 nm indicating direct photolysis should occur (Gore et al, 1971). When malathion was exposed to UV light, malathion monoacid, malathion diacid, 0,0-diethyl phosphorothioic acid, dimethyl phosphate, and phosphoric acid were formed (Mosher and Kadoum, 1972). 

The following metabolites were identified in a soil-oat system paraoxon, aminoparathion, 4-nitrophenol, and 4-aminophenol (Lichtenstein, 1980 Lichtenstein et al., 1982). Mick and Dahm (1970) reported that Rhizobium sp. converted 85% [ CJparathion to aminoparathion and 10% diethyl phosphorothioic acid in 1 d. 

Diethyl phosphate, see Sulfotepp Diethyl phosphoric acid, see Diazinon. Parathion Diethyl phosphorothioate, see Diazinon 0,0-Diethyl phosphorothioic acid, see Chlorpyrifos, Diazinon. Malathion, Parathion Diethyl sulfide, see Chlorpyrifos Diethyl thiomalate, see Malathion Diethylthiomaleate, see Malathion Diethylthiophosphoric acid, see Diazinon. Parathion Diethyl-0-thiophosphoric acid, see Parathion... 

Parathion is also metabolized to diethyl phosphorothioic acid and -nitrophenol in a reaction requiring a cytochrome P-4Jg-containing monooxygenase enzyme system (, 4). Studies with H. 0 have indicated that water in addition to molecular oxygen and NADPH is required in this reaction ( ). Diethyl phosphate and -nitro-phenol can also be formed from parathion in a monooxygenase-catalyzed reaction (6). 

Diethyl phosphorothioic acid and diethyl phosphoric acid have been identified as metabolites of [14C]diazinon following a single intravenous injection in female Beagle dogs (Iverson et al. 1975). In vitro metabolism of ethoxy-l-[14C]diazinon was carried out using rat liver microsomes (Yang et al. 1971). Diazinon was metabolized in a complex reaction via cytochrome P-450 to diazoxon and 2-isopropyl -... 

Following an intravenous injection of [ethyl-14C]diazinon to female Beagle dogs, approximately 58% of the radioactivity was recovered in the urine within 24 hours as diethyl phosphorothioic acid (42%) and diethyl phosphoric acid (16%). No intact diazinon was excreted (Iverson et al. 1975). 

On the other hand, parathion can be dearylated by glutathione S-transferase to produce diethyl phosphorothioic acid and S-(p-nitrophenyl) glutathione (Figure 8.22). 

The metabolic and/or hydrolytic products of parathion encountered as residues in the urine include both diethyl phosphoric acid and diethyl phosphorothioic acid, most probably as their salts (potassium or sodium). Derivatization of these residues with diazomethane would result in the formation of three trialkyl phosphate compounds, namely, 0,0-diethyl O-methyl phosphate (DEMMP), 0,0-diethyl 0-methyl phosphoro-thionate (DEMMTP), and 0,0-diethyl S-methyl phosphorothiolate (DEMMPTh). Earlier (15), it had been shown by combined gas chromatography-mass spectrometry and other analytical data that a later-eluting major product ca. 85%) of the methylation of diethyl phosphorothioic acid formed under the conditions of the analytical method was DEMMPTh, and the minor product formed (ca. 15%) was DEMMTP. Accordingly, all three trialkyl phosphates were observed and confirmed by mass spectrometry in the analysis of the human urine extract. Sufficient internal bond energy differences are associated with the isomeric structures DEMMPTh and DEMMTP that qualitatively and quantitatively dissimilar fragmentation patterns are observed for both isomers as can be seen from the mass spectra of these compounds shown in Figure 4. 

A reinvestigation of the reaction of 5 6-anhydro-1,2-0-isopro-pylidene-k-D-glucofuranose with phosphorothioic acids, (EtO) P(S)OH (see Vol. 14f P i>7), has shown that the products are an equilibrium mixture of the esters (27) - (29) In the case of the diethyl-phosphorothioic acid, the cyclic ester (28) predominated if ethanol was continually azeotropically removed from the reaction mixture. More vigorous conditions gave the episulphide (30) irreversibly. 

Chemical name Phosphorothioic acid O.O-diethyl 0-(3,5,6-trichloro-2-pyridinyl) ester... 

Diazinon (phosphorothioic acid 0,0-diethyl 0-(6-mcthyl-2-(l-mcthylcthyl)-4-pyrimidinyl) ester) is an organophosphorus compound with an anticholinesterase mode of action. It is used extensively to control hies, lice, insect pests of ornamental plants and food crops, as well as nematodes and soil insects in lawns and croplands. Diazinon degrades rapidly in the environment, with half-time persistence usually less than 14 days. But under conditions of low temperature, low moisture, high alkalinity, and lack of suitable microbial degraders, diazinon may remain biologically active in soils for 6 months or longer. 

Phosphoric acid, tri-2-tolyl ester, see Tri-o-cresyl phosphate Phosphorothioic acid, 0,0-diethyl 0-(4-nitrophenyl) ester, see Parathion... 

Chloroform, Chloropicrin, 1,1-Dichloroethylene, Endrin, Hexachlorocyclopentadiene, Methyl chloride. Methylene chloride, Tetrachloroethylene, 1,1,1 -Trichloroethane, Trichloroethylene Phosphine, see Pentachlorobenzene, Phorate Phosphoric acid, see Dichlorvos, Ethephon. Glvphosate. Malathion, Mevinphos, Parathion, Sulfotepp, Tributyl phosphate, Trichlorfon Phosphoric acid, dimethyl ester, see Mevinphos, Oxvdemeton-methvl Phosphorothioic acid, see Parathion Photoaldrin, see Aldrin Photoaldrin chlorohydrin, see Dieldrin Photodieldrin, see Aldrin, Dieldrin Photoheptachlor, see Heptachlor Photoketoaldrin, see Aldrin Phthalaldehyde, see Naphthalene Phthalaldehydes, see Tolnene Phthalic acid, see Anthracene, Benzo[a]anthracene, Benzyl bntyl phthalate, Dichlone. Diethyl phthalate, Dimethyl phthalate, Naphthalene, Naptalam. I ene... 

Phcsphorodichloridic Acid, Ethyl Ester Phosphorothioic Acid, 0,0-Diethyl Ester Phosphorothioic Acid, 0,0-Diethyl O-P-Ni Ester... 

G-2448D, Basudin, Diazol, Garden Tox, Sarodex, Spectracide, 0,0-diethyl-0-(2-isopropyl-6-methyl-4-pyrimidinyl) phosphorothioate, phosphorothioic acid 0,0-diethyl-0-[6-methyl-2-(l-methylethyl)-4-pyrimidinyl] ester, thiophosphoric acid 2-isopropyl-4-methyl-6-pyrimidynyl diethyl ester. 

SYNS PHOSPHOROTHIOIC ACID, 0,0-DIETHYL o-(4-(((((METHYLAi nNO)CARBONYL)OXY)L IINO)METHVL) PHENYL)ESTER R 14487 STAUFFER R 14487... 

DKB170 CAS 3513-92-6 HR 3 0,0-DIETHYL o-TETRAHYDROFURFUR-YL ESTER PHOSPHOROTHIOIC ACID... 

SYNS BAYER 19564 ENT 23,444 PHOSPHOROTHIOIC ACID, o,o-DIETHYL o-((TETRAHYDRO-2-FURANYL)METHYL) ESTER... 

EN 18133 ENT 25,580 EXPERIMENTAL NEMA-TOCIDE 18,133 NEMAFOS NEMAPHOS NEMA-TOCIDE PHOSPHOROTHIOIC ACID-O.O-DIETHYL-0-2-PYRAZINYL ESTER PYRAZINOL-O-ESTER with 0,0-DIETHYL PHOSPHOROTHIOATE RCRA WASTE NUMBER P404 THIONAZIN ZINOPHOS... 

SYN PHOSPHOROTHIOIC ACID-0,0-DIETHYL, 0-(p-NITROPHENYL)ESTER, mixed with compressed gas... 

PHK250 CAS 3734-95-0 HR 3 PHOSPHOROTHIOIC ACID-S-(((1-CYANO-1 -METHYL-ETHYL)CAR-BAM0YL)METHYL)-0,0-DIETHYL ESTER... 

DICHLORO-PHENOL-O-ESTER with 0,0-DIETHYL PHOSPHOROTHIOATE see DFK600 (2,4-DICHLOROPHENOXY)ACETIC ACID, ISOPROPYL ESTER see lOYOOO (2-4-DICHLOROPHENOXY)ACETIC ACID-1-METHYLETHYL ESTER (9CI) see lOYOOO... 

---