Butafenacil

Last updated
Butafenacil
Butafenacil.svg
Names
IUPAC name
1-(Allyloxy)-2-methyl-1-oxo-2-propanyl 2-chloro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)-3,6-dihydro-1(2H)-pyrimidinyl]benzoate
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.112.043 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 603-837-5
PubChem CID
UNII
  • InChI=1S/C20H18ClF3N2O6/c1-5-8-31-17(29)19(2,3)32-16(28)12-9-11(6-7-13(12)21)26-15(27)10-14(20(22,23)24)25(4)18(26)30/h5-7,9-10H,1,8H2,2-4H3 Yes check.svgY
    Key: JEDYYFXHPAIBGR-UHFFFAOYSA-N Yes check.svgY
  • CC(C)(C(=O)OCC=C)OC(=O)C1=C(C=CC(=C1)N2C(=O)C=C(N(C2=O)C)C(F)(F)F)Cl
Properties [1]
C20H18ClF3N2O6
Molar mass 474.82 g·mol−1
Density 1.37 g/mL
Melting point 113 °C (235 °F; 386 K)
10 mg/L (20 °C)
log P 3.2
Hazards
GHS labelling: [2]
GHS-pictogram-silhouette.svg GHS-pictogram-pollu.svg
Warning
H373, H410
P260, P273, P314, P391, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Butafenacil is the ISO common name [3] for an organic compound of the pyrimidinedione chemical class used as an herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase to control broadleaf and some grass weeds in crops including cereals and canola.

Contents

History

In 1985, chemists at the Dr. R. Maag subsidiary of Hoffmann-La Roche filed patents for uracil derivatives which had herbicidal activity. [4] In 1990 the agrochemical interests of Maag were sold to Ciba-Geigy [5] and work continued to optimise this area of biological activity. By 1993 a patent claiming specific ester derivatives including butafenacil was published. [6] This was developed for the market under the code number CGA276854 and launched in 2001. [1] [7] By that time, further mergers in the industry meant that the product was supplied by Syngenta [8] with brand names including B Power. [9]

Synthesis

Key step in butafenacil synthesis Butafenacil synthesis.svg
Key step in butafenacil synthesis

As described in the Ciba-Geigy patent, the key step in the preparation of butafenacil involved the reaction between a phenyl isocyanate and an amine. Ethyl 2-chloro-5-isocyanato-benzoate and ethyl 3-amino-4,4,4-trifluorocrotonate were reacted in the presence of a base to form a substituted urea intermediate which was cyclised to the pyrimidinedione, as shown. Further standard chemical transformations generated the final product. [6]

Mechanism of action

Butafenacil works by inhibiting protoporphyrinogen IX oxidase (PPO), preventing chlorophyll formation, and resulting in the accumulation of protoporphyrin IX which is a potent photosensitizer. This activates oxygen, causing lipid peroxidation with rapid loss of membrane integrity and function. The effects visible on whole plants are chlorosis and necrosis. [7] [10]

Usage

Butafenacil is registered for use in Australia, [9] [11] Argentina, Brazil, Japan, and Thailand but not now in the European Union or USA, although it was conditionally given approval there in 2003. [1] [12]

The herbicide controls annual and perennial broadleaf weeds and some grasses. It has little selectivity so is usually applied before sowing crop seeds. It is effective post-emergence on a very wide range of species including Arctotheca calendula , Avena fatua , Bidens pilosa , Boerhavia diffusa , Brassica napus , Brassica tournefortii , Bromus diandrus , Capsella bursa-pastoris , Carthamus lanatus , Chenopodium album , Chenopodium pumilio , Cirsium acaule , Echinochloa crus-galli , Emex australis , Erodium botrys , Erodium cicutarium , Festuca arundinacea , Hordeum leporinum , Hypochaeris radicata , Lamium amplexicaule , Lolium rigidum , Lupinus angustifolius , Malva parviflora , Medicago sativa , Modiola caroliniana , Panicum capillare , Panicum effusum , Phalaris paradoxa , Polygonum aviculare , Portulaca oleracea , Raphanus raphanistrum , Rapistrum rugosum , Rumex acetosella , Rumex crispus , Salvia reflexa , Sisymbrium orientale , Sonchus oleraceus , Tribulus terrestris , Urochloa panicoides , Urtica urens , Vicia sativa and Vulpia bromoides . The product is typically used at application rates of 10 g a.i. per hectare, often in combination with other herbicides such as paraquat and glyphosate in direct drilling of cereals and canola. [9]

Human safety

The LD50 of butafenacil is over 5000 mg/kg (rats, oral), which means that it is of low toxicity by oral ingestion. [1] The toxicity of protoporphyrinogen oxidase inhibitors has been reviewed. [13]

Related Research Articles

<span class="mw-page-title-main">Novartis</span> Swiss multinational pharmaceutical corporation

Novartis AG is a Swiss multinational pharmaceutical corporation based in Basel, Switzerland. Consistently ranked in the global top five, Novartis is one of the largest pharmaceutical companies in the world and was the fourth largest by revenue in 2022.

<span class="mw-page-title-main">Diazinon</span> Chemical compound

Diazinon, a colorless to dark brown liquid, is a thiophosphoric acid ester developed in 1952 by Ciba-Geigy, a Swiss chemical company. 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. Diazinon is a major component in the "Golden Fleece" brand sheep dip. Residential uses of diazinon were outlawed in the U.S. in 2004 because of human health risks but it is still approved for agricultural uses. An emergency antidote is atropine.

<span class="mw-page-title-main">Syngenta</span> Global provider of agricultural science and technology

Syngenta is a provider of agricultural science and technology, in particular seeds and pesticides with its management headquarters in Basel, Switzerland. It is owned by ChemChina, a Chinese state-owned enterprise.

<span class="mw-page-title-main">Diquat</span> Chemical compound

Diquat is the ISO common name for an organic dication that, as a salt with counterions such as bromide or chloride is used as a contact herbicide that produces desiccation and defoliation. Diquat is no longer approved for use in the European Union, although its registration in many other countries including the USA is still valid.

<span class="mw-page-title-main">Phenoxy herbicide</span> Class of herbicide

Phenoxy herbicides are two families of chemicals that have been developed as commercially important herbicides, widely used in agriculture. They share the part structure of phenoxyacetic acid.

<span class="mw-page-title-main">Protoporphyrinogen oxidase</span>

Protoporphyrinogen oxidase or protox is an enzyme that in humans is encoded by the PPOX gene.

Acibenzolar-<i>S</i>-methyl Chemical compound

Acibenzolar-S-methyl is the ISO common name for an organic compound that is used as a fungicide. Unusually, it is not directly toxic to fungi but works by inducing systemic acquired resistance, the natural defence system of plants.

<span class="mw-page-title-main">Azoxystrobin</span> Chemical compound

Azoxystrobin is a broad spectrum systemic fungicide widely used in agriculture to protect crops from fungal diseases. It was first marketed in 1996 using the brand name Amistar and by 1999 it had been registered in 48 countries on more than 50 crops. In the year 2000 it was announced that it had been granted UK Millennium product status.

<span class="mw-page-title-main">Sulfentrazone</span> Chemical compound

Sulfentrazone is the ISO common name for an organic compound used as a broad-spectrum herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase. It was first marketed in the US in 1997 by FMC Corporation with the brand name Authority.

<span class="mw-page-title-main">Saflufenacil</span> Chemical compound

Saflufenacil is the ISO common name for an organic compound of the pyrimidinedione chemical class used as an herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase to control broadleaf weeds in crops including soybeans and corn.

<span class="mw-page-title-main">Mesotrione</span> Chemical compound used as an herbicide

Mesotrione is a selective herbicide used mainly in maize crops. It is a synthetic compound inspired by the natural substance leptospermone found in the bottlebrush tree Callistemon citrinus. It inhibits the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD) and is sold under brand names including Callisto and Tenacity. It was first marketed by Syngenta in 2001.

<span class="mw-page-title-main">Acifluorfen</span> Chemical compound

Acifluorfen is the ISO common name for an organic compound used as an herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase which is necessary for chlorophyll synthesis. Soybeans naturally have a high tolerance to acifluorfen and its salts, via metabolic disposal by glutathione S-transferase. It is effective against broadleaf weeds and grasses and is used agriculturally on fields growing soybeans, peanuts, peas, and rice.

4-Hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors are a class of herbicides that prevent growth in plants by blocking 4-Hydroxyphenylpyruvate dioxygenase, an enzyme in plants that breaks down the amino acid tyrosine into molecules that are then used by plants to create other molecules that plants need. This process of breakdown, or catabolism, and making new molecules from the results, or biosynthesis, is something all living things do. HPPD inhibitors were first brought to market in 1980, although their mechanism of action was not understood until the late 1990s. They were originally used primarily in Japan in rice production, but since the late 1990s have been used in Europe and North America for corn, soybeans, and cereals, and since the 2000s have become more important as weeds have become resistant to glyphosate and other herbicides. Genetically modified crops are under development that include resistance to HPPD inhibitors. There is a pharmaceutical drug on the market, nitisinone, that was originally under development as an herbicide as a member of this class, and is used to treat an orphan disease, type I tyrosinemia.

<span class="mw-page-title-main">Crop desiccation</span>

Pre-harvest crop desiccation refers to the application of an agent to a crop just before harvest to kill the leaves and/or plants so that the crop dries out from environmental conditions, or "dry-down", more quickly and evenly. In agriculture, the term desiccant is applied to an agent that promotes dry down, thus the agents used are not chemical desiccants, rather they are herbicides and/or defoliants used to artificially accelerate the drying of plant tissues. Desiccation of crops through the use of herbicides is practiced worldwide on a variety of food and non-food crops.

<span class="mw-page-title-main">Bifenox</span> Chemical compound

Bifenox is the ISO common name for an organic compound used as an herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase which is necessary for chlorophyll synthesis.

<span class="mw-page-title-main">Fomesafen</span> PPOi herbicide

Fomesafen is the ISO common name for an organic compound used as an herbicide. It acts by inhibiting the enzyme protoporphyrinogen oxidase (PPO) which is necessary for chlorophyll synthesis. Soybeans naturally have a high tolerance to fomesafen, via metabolic disposal by glutathione S-transferase. As a result, soy is the most common crop treated with fomesafen, followed by other beans and a few other crop types. It is not safe for maize/corn or other Poaceae.

<span class="mw-page-title-main">Fluazifop</span> ACCase herbicide, fop, anti-grass

Fluazifop is the common name used by the ISO for an organic compound that is used as a selective herbicide. The active ingredient is the 2R enantiomer at its chiral centre and this material is known as fluazifop-P when used in that form. More commonly, it is sold as its butyl ester, fluazifop-P butyl with the brand name Fusilade.

<span class="mw-page-title-main">Aclonifen</span> Chemical compound

Aclonifen is a diphenyl ether herbicide which has been used in agriculture since the 1980s. Its mode of action has been uncertain, with evidence suggesting it might interfere with carotenoid biosynthesis or inhibit the enzyme protoporphyrinogen oxidase (PPO). Both mechanisms could result in the observed whole-plant effect of bleaching and the compound includes chemical features that are known to result in PPO effects, as seen with acifluorfen, for example. In 2020, further research revealed that aclonifen has a different and novel mode of action, targeting solanesyl diphosphate synthase which would also cause bleaching.

<span class="mw-page-title-main">Tribenuron</span> Chemical compound

Tribenuron in the form of tribenuron-methyl is a sulfonylurea herbicide. Its mode of action is the inhibition of acetolactate synthase, group 2 of the Herbicide Resistance Action Committee's classification scheme.

3-(Difluoromethyl)-1-methyl-1<i>H</i>-pyrazole-4-carboxylic acid Chemical compound

3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid is a chemical compound which is used commercially as an intermediate to seven fungicides which act by inhibition of succinate dehydrogenase (SDHI). It consists of a pyrazole ring with difluoromethyl, methyl and carboxylic acid groups attached in specific positions.

References

  1. 1 2 3 4 Pesticide Properties Database. "Butafenacil". University of Hertfordshire.
  2. "Butafenacil". pubchem.ncbi.nlm.nih.gov. Retrieved 2021-03-17.
  3. "Compendium of Pesticide Common Names: butafenacil". BCPC.
  4. USpatent 4746352,Wenger J.&Winternitz P.,"3-(5-Carboxy-4-Substituted-Phenyl)-(thio) Uracil esters and salts",issued 1988-05-24, assigned to Hoffmann-La Roche Inc.
  5. "Ciba-Geigy Ltd. History". fundinguniverse.com. Retrieved 2021-03-18.
  6. 1 2 USpatent 5183492,Suchy M.; Winternitz P.& Zeller M.,"Herbicidal 3-aryluracils",issued 1993-02-02, assigned to Ciba-Geigy Ag
  7. 1 2 Selby, Thomas P.; Ruggiero, Marc; Hong, Wonpyo; Travis, D. Andrew; Satterfield, Andrew D.; Ding, Amy X. (2015). "Broad-Spectrum PPO-Inhibiting N-Phenoxyphenyluracil Acetal Ester Herbicides". Discovery and Synthesis of Crop Protection Products. ACS Symposium Series. Vol. 1204. pp. 277–289. doi:10.1021/bk-2015-1204.ch020. ISBN   9780841231023.
  8. "Syngenta Begins Trading on the New York Stock Exchange". PRNewsWire. 13 November 2000. Archived from the original on June 30, 2015. Retrieved 18 March 2021.
  9. 1 2 3 "B Power herbicide". syngenta.com.au. Retrieved 2021-03-18.
  10. Theodoridis, George (2016). "Carboxylic-Acid-Containing Protoporphyrinogen-IX-Oxidase-Inhibiting Herbicides". Bioactive Carboxylic Compound Classes: Pharmaceuticals and Agrochemicals. pp. 347–356. doi:10.1002/9783527693931.ch26. ISBN   9783527339471.
  11. "Agricultural and veterinary chemicals" (PDF). Commonwealth of Australia Gazette. 2. Australian Pesticides and Veterinary Medicines Authority: 8. 2019-01-29. Retrieved 2021-03-17.
  12. Tompkins, J (2003-09-29). "Butafenacil technical" (PDF). www3.epa.gov. Retrieved 2021-03-19.
  13. Dayan, Franck E.; Duke, Stephen O. (2010). "Protoporphyrinogen Oxidase-Inhibiting Herbicides". Hayes' Handbook of Pesticide Toxicology. pp. 1733–1751. doi:10.1016/B978-0-12-374367-1.00081-1. ISBN   9780123743671.