Zytron

Zytron, also known as DMPA, is a chlorophenoxy herbicide.^[1] It controls crabgrass and other weeds in turf preëmergently, and ants, chinch bugs and grubs.^[2] It is used on baseball pitches in Australia.^[3]

Zytron

Names
Preferred IUPAC name N-[(2,4-Dichlorophenoxy)-methoxyphosphinothioyl]propan-2-amine
Other names DMPA O-2,4-Dichlorophenyl O-methyl isopropyl phosphoramidothioate
Identifiers
CAS Number	299-85-4 Y
3D model (JSmol)	Interactive image
ChemSpider	8940 N
DrugBank	DB11768
PubChem CID	9299
UNII	IK51552IFH
CompTox Dashboard (EPA)	DTXSID1058052
InChI InChI=1S/C10H14Cl2NO2PS/c1-7(2)13-16(17,14-3)15-10-5-4-8(11)6-9(10)12/h4-7H,1-3H3,(H,13,17) Key: PJFGPJQBWSEWKX-UHFFFAOYSA-N
SMILES CC(C)NP(=S)(OC)OC1=C(C=C(C=C1)Cl)Cl
Properties
Chemical formula	C10H14Cl2NO2PS
Molar mass	314.16 g·mol−1
Appearance	Solid[1]
Vapor pressure	6.14x10−5 mm Hg[1]
Hazards
Lethal dose or concentration (LD, LC):
LD50 (median dose)	270 mg/kg (rat, oral) >1000 mg/kg (dog, oral) [1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Zytron inhibits microtubule assembly, preventing mitosis. making it a Group 3 / D / K1, similar to dinitroanilines like trifluralin.^[4] It was tested and commercially available in the US in 1959, and applied at 10-20 lbs per acre on turf,^[5] a high rate compared to other herbicides.

Zytron disappears almost completely from the body within one hour of mammalian exposure.^[2] It does not accumulate in soil and is non-harmful to microflora.^[6] DMPA has in testing been applied at rates as high as 67 lbs per acre.^[7]

Zytron may cause neurotoxicity in chickens. It is an organophosphorus ester, and other such chemicals are known to cause similar neurotoxicity. 100 mg/kg daily for 10 days was considered the minimum effective dose to observably alter hens' behaviour.^[8]

Zytron has been sold under the tradenames "Dow Crabgrass Killer", "Dow 1329", "Dowco 118" and "T-H Crabgrass Killer."^[9][10]