Title: Metribuzin
CAS Registry Number: 21087-64-9
CAS Name: 4-Amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4
H)-one
Synonyms: 4-amino-6-
tert-butyl-3-(methylthio)-
as-triazin-5(4
H)-one
Manufacturers' Codes: Bay 94337
Trademarks: Lexone (DuPont); Sencor (Bayer CropSci.); Sencoral (Bayer CropSci.)
Molecular Formula: C8H14N4OS
Molecular Weight: 214.29
Percent Composition: C 44.84%, H 6.59%, N 26.15%, O 7.47%, S 14.96%
Literature References: Pre- and post-emergence triazone herbicide. Prepn:
BE 697083; K. Westphal
et al., US 3671523 (1967, 1972 both to Bayer AG). Physicochemical properties, toxicology and herbicidal activity: L. Eue,
Pflanzenschutz-Nachr. 25, 175 (1972). Toxicity data: E. Loeser, G. Kimmerle,
ibid. 186. HPLC determn in plant tissues: C. E. Parker, G. H. Degen,
J. Liq. Chromatogr. 6, 725 (1983).
Properties: White crystalline solid, mp 125-126.5°. d420 1.28. Vapor pressure at 20°: <10-5 mm Hg. Sol in methanol, ethanol. Soly in water: 1200 ppm. LD50 orally in rats: 2200 mg/kg; LC50 in rainbow trout: >10 ppm (Loeser, Kimmerle).
Melting point: mp 125-126.5°
Density: d420 1.28
Toxicity data: LD50 orally in rats: 2200 mg/kg; LC50 in rainbow trout: >10 ppm (Loeser, Kimmerle)
CAUTION: Potential symptoms of overexposure in exptl animals are CNS depression; thyroid, liver and enzyme changes.
See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 216.
Use: Herbicide.