Metribuzin

Description

Metribuzin · CAS 21087-64-9 · C8H14N4OS. UNII QO836138OV. Boiling Point: 132 °C @ 2 Pa; Melting Point: 257 °F (NIOSH, 2024); Melting Point: 126.2 °C.

Identification

CAS Registry Number	21087-64-9
PubChem CID	30479
Molecular formula	C8H14N4OS
IUPAC name	4-amino-6-tert-butyl-3-methylsulfanyl-1,2,4-triazin-5-one
UNII (FDA)	QO836138OV

Computed Descriptors

Molecular Weight	214.29
XLogP3	1.7
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	2
Exact Mass	214.08883226
Monoisotopic Mass	214.08883226
Topological Polar Surface Area	96.4
Heavy Atom Count	14
Formal Charge	0

Physical & Chemical Properties

Boiling Point	132 °C @ 2 Pa
Melting Point	257 °F (NIOSH, 2024)
Melting Point	126.2 °C
Melting Point	125 °C
Melting Point	257 °F
Solubility	0.1 % (NIOSH, 2024)
Solubility	In water, 1.05X10+3 mg/l @ 20 °C
Solubility	0.1%
Density	1.28 @ 20 °C/4 °C
Density	1.28 g/cm³

Physical description & handling notes

• Metribuzin is a colorless crystalline solid. Used as an herbicide. (NIOSH, 2024)
• Colorless, crystalline solid. [herbicide]; [NIOSH]
• COLOURLESS-TO-WHITE CRYSTALS WITH CHARACTERISTIC ODOUR.
• Colorless, crystalline solid.
• Colorless, crystalline solid. [herbicide]
• Colorless crytals

GHS Hazard Classification

Reported hazard statements	H302, H373, H400, H410, H331 (23.6%), H303

Documented Uses

• Metribuzin is a herbicide used to control weeds in alfalfa, asparagus, barley, carrots, corn, peas, potatoes, soybeans, sugarcane, tomatoes, turf grass, and wheat. [ACGIH]
• Controls a large number of grass and broadleaf weeds in agricultural crops.
• Use of metribuzin in the United States was 4.8 million lbs in the year 1987.
• Absorbed through the leaves from surface treatment, but the major significant route for uptake is via root system. ... Uptake through the roots is best described as osmotic diffusion. Metribuzin is translocated upward in the xylem and moves distally when applied at the base of leaves.
• After absorption, it is rapidly distributed and rapidly excreted unchangd or metabolized (oxidized) and excreted via the urine.
• When (14)C metribuzin was applied to tomatoes, preliminary evidence indicated that the first (14)C metabolite may be a complex with deaminated diketometribuzin or metribuzin.

Synonyms

METRIBUZIN; 21087-64-9; Lexone; Sencor; Metribuzine; Sencorex; Zenkor; Sencoral; Senkor; Lexone DF; Sencor DF; Lexone 4L; Sencor 4F; Sencorer; Bayer 6159H; Bayer 6443H

Frequently Asked Questions

What are the CAS number and molecular formula of Metribuzin?

CAS 21087-64-9; molecular formula C8H14N4OS; molecular weight — g/mol.

What other names is Metribuzin known by?

METRIBUZIN, 21087-64-9, Lexone, Sencor, Metribuzine, Sencorex.

Is Metribuzin classified as hazardous?

Hazard statements reported: H302, H373, H400, H410, H331.

What are the key physical properties of Metribuzin?

Boiling Point: 132 °C @ 2 Pa; Melting Point: 257 °F (NIOSH, 2024); Melting Point: 126.2 °C; Melting Point: 125 °C.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.