Title: Diazinon
CAS Registry Number: 333-41-5
CAS Name: Phosphorothioic acid O,O-diethyl O-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester
Additional Names: thiophosphoric acid 2-isopropyl-4-methyl-6-pyrimidyl diethyl ester; O,O-diethyl O-2-isopropyl-4-methyl-6-pyrimidyl thiophosphate; diethyl 2-isopropyl-4-methyl-6-pyrimidyl thionophosphate; dimpylate
Manufacturers' Codes: G-24480
Trademarks: Antigal (Streuli); Basudin (Syngenta); Diazol (Makhteshim-Agan); HelfaCat (Helvepharm); HelfaDog (Helvepharm); Neocidol (Novartis); Parasitex (Virbac); Sarolex; Spectracide; Taberdog (Nipa); Tabergat (Nipa)
Molecular Formula: C12H21N2O3PS
Molecular Weight: 304.35
Percent Composition: C 47.36%, H 6.95%, N 9.20%, O 15.77%, P 10.18%, S 10.54%
Literature References: Cholinesterase inhibitor. Prepn: Gysin, Margot, US 2754243 (1956 to Geigy). Insecticidal properties: Gasser, Z. Naturforsch. 8b, 225 (1953). Toxicity data: T. B. Gaines, Toxicol. Appl. Pharmacol. 14, 515 (1969). Review of toxicology and human exposure: Toxicological Profile for Diazinon (PB97-121107, 1996) 245 pp.
Properties: Liquid. Faint ester-like odor. d420 1.116-1.118. bp0.002 83-84°. nD20 1.4978-1.4981. Vapor pressure at 20°: 1.4´10-4; at 40°: 1.1´10-3 (~5 times vapor pressure of parathion). Volatility at 20°: 2.4 mg/m3; at 40°: 17.6 mg/m3. Decomposes above 120°. Soly in water at 20°: 0.004%. Miscible with alcohol, ether, petr ether, cyclohexane, benzene, and similar hydrocarbons. More stable in alkaline formulations, then when at neutral or acid pH. LD50 in male, female rats (mg/kg): 250, 285 orally (Gaines).
Boiling point: bp0.002 83-84°
Index of refraction: nD20 1.4978-1.4981
Density: d420 1.116-1.118
Toxicity data: LD50 in male, female rats (mg/kg): 250, 285 orally (Gaines)
CAUTION: Potential symptoms of overexposure are eye irritation; miosis, blurred vision; dizziness, confusion, weakness, convulsions; dyspnea; salivation, abdominal cramps, nausea, vomiting. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 92.
Use: Insecticide.
Therap-Cat-Vet: Ectoparasiticide.
Diaziquone Diazoacetic Ester Diazoaminobenzene Diazolidinyl Urea Diazomethane

CAS number 333-41-5 YesY
PubChem 3017
ChemSpider 2909 YesY
KEGG D07856 YesY
ChEBI CHEBI:34682 YesY
ATCvet code QP53AF03
Jmol-3D images Image 1
Molecular formula C12H21N2O3PS
Molar mass 304.35 g mol−1
Appearance Colorless to dark brown liquid
Density 1.116-1.118 g/cm3 at 20 °C[1]
Solubility in water 40 mg/L[2]
log P 3.81 (octanol/water)[3]
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Diazinon (IUPAC name: O,O-Diethyl O-[4-methyl-6-(propan-2-yl)pyrimidin-2-yl] phosphorothioate, INN - Dimpylate), a colorless to dark brown liquid, is a thiophosphoric acid ester developed in 1952 by Ciba-Geigy, a Swiss chemical company (later Novartis and then Syngenta). It is a nonsystemic organophosphate insecticide formerly used to control cockroaches, silverfish, ants, and fleas in residential, non-food buildings. Diazinon was heavily used during the 1970s and early 1980s for general-purpose gardening use and indoor pest control. A bait form was used to control scavenger wasps in the western U.S. Diazinon is used in flea collars for domestic pets in Australia and New Zealand. Residential uses of diazinon were outlawed in the U.S. in 2004 but it is still approved for agricultural uses. An emergency antidote is atropine.[4]