Jump to content

Imazosulfuron

From Wikipedia, the free encyclopedia
Imazosulfuron
Names
Preferred IUPAC name
1-(2-chloroimidazo[1,2-a]pyridin-3-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea
Other names
URA-09800-H-0-WG
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.127.566 Edit this at Wikidata
EC Number
  • 602-788-7
KEGG
UNII
  • InChI=1S/C14H13ClN6O5S/c1-25-9-7-10(26-2)18-13(17-9)19-14(22)20-27(23,24)12-11(15)16-8-5-3-4-6-21(8)12/h3-7H,1-2H3,(H2,17,18,19,20,22)
    Key: NAGRVUXEKKZNHT-UHFFFAOYSA-N
  • COC1=CC(=NC(=N1)NC(=O)NS(=O)(=O)C2=C(N=C3N2C=CC=C3)Cl)OC
Properties
C14H13ClN6O5S
Molar mass 412.81 g·mol−1
Density 1.652 g/mL[1]
Melting point 198 °C (388 °F; 471 K)[1]
429 mg/L at pH 7; 3936 mg/L at pH 9[1]
Vapor pressure <3.5 μPa[1]
Hazards
GHS labelling:[1]
GHS09: Environmental hazard
Warning
H410
P273, P391, P501
Lethal dose or concentration (LD, LC):
  • >5000 mg/kg (rat, oral)
  • >2000mg/kg (rat, dermal)[1]
>2.12 mg/L (rat, inhalation)[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Imazosulfuron is a selective sulfonylurea herbicide to control sedges and broadleaf weeds. It is a preёmergent and postemergent herbicide. In the US, it was first registered in 2010 and is approved for residential and commercial use on turfgrass, rice, tomatoes and peppers.[2][1]

It is not approved in the European Union.[2]

The maximum application rate in the US is 0.3 lbs per acre (0.3 kg/Ha) for food use, or 0.67 lbs per acre (0.75 kg/Ha) for turf.[1]

Mode of action

[edit]

Imazosulfuron inhibits the enzyme acetolactate synthase, preventing synthesis of branch chain amino acids like valine, leucine, and isoleucine, which are necessary for cell formation. It is absorbed through roots and foliage, and translocates through xylem and phloem.[1]

Imazosulfuron's mode of action makes its HRAC classification Group B (Australia, Global) or Group 2 (numeric).[2][3]

Environmental behaviour

[edit]

Imazosulfuron is moderately mobile in soil, but is not volatile and so will not be moved atmospherically after application. It degrades primarily through aerobic and anaerobic biodegradation and aqueous photolysis. In soil, its half life is expected to be several weeks, but the water halflife is 3.5 days due to photolysis. Movement is expected by runoff and leaching, but contamination is not expected to be persistent.[1]

It is practically non-toxic to birds, mammals and honeybees, and no significant toxicity was found to fish.[1]

Safety

[edit]

Imazosulfuron is of low toxicity via oral, inhalatory or dermal exposure. It is not an eye nor skin irritant, nor a skin sensitizer. In chronic exposure trials, the liver is the main affected organ, though rats given >1000mg/kg/day (equivalent to about a shot-glass of pure imazosulfuron daily for an 80kg person) developed eye problems after three months. Chronic exposure studies often showed weight gain or loss. Mild to moderate thyroid effects were reported only in the study of chronic exposure to dogs. Subchronic trials showed no neurotoxicity.[1]

No developmental or reproductive toxicity was found except at the highest dosage tested (892mg/kg/day) on rats. No evidence of carcinogenicity was found.[1]

References

[edit]
  1. ^ a b c d e f g h i j k l m "PESTICIDE FACT SHEET: Imazosulfuron" (PDF). UNITED STATES ENVIRONMENTAL PROTECTION AGENCY. December 14, 2010. Retrieved 7 June 2025.
  2. ^ a b c Lewis, Kathleen A.; and Green, Andrew (18 May 2016). "An international database for pesticide risk assessments and management". Human and Ecological Risk Assessment: An International Journal. 22 (4): 1050–1064. Bibcode:2016HERA...22.1050L. doi:10.1080/10807039.2015.1133242.
  3. ^ "Australia Herbicide Classification Lookup". Herbicide Resistance Action Committee. Retrieved 7 June 2025.