314-40-9 Bromacil

IUPAC name 5-bromo-3-sec-butyl-6-methyluracil Molecular formula C9Hi3BrN202 

Uses Bromacil is a colorless crystalline solid. It is used for the control of annual and perennial grasses, broadleaf weeds, and woody plants.1213 Bromacil is a herbicide used for bush weed control on non-cropland areas. It is especially useful against perennial grasses. It is also used for selective weed control in pineapple and citrus crops. It interferes with photosynthesis of plants. It is available in granular, liquid, water-soluble liquid, and wettable powder formulations. 

Toxicity The acute oral LD50 for rats is 5,200 mg/kg, whereas the acute dermal LD50 to rabbits is greater than 5,000 mg/kg. The primary skin irritation and eye irritation to rabbits is moderate. The acute inhalation LC50 to rats is greater than 4.8 mg/L. Studies on carcinogenicity are inadequate for a meaningful evaluation and require more data.25 

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Urea and uracil herbicides tend to be persistent in soils and may carry over from one season to the next (299). However, there is significant variation between compounds. Bromacil is debrominated under anaerobic conditions but does not undergo further transformation (423), linuron is degraded in a field soil and does not accumulate or cause carryover problems (424), and terbacd [5902-51-2] is slowly degraded in a Russian soil by microbial means (425). The half-hves for this breakdown range from 76 to 2,475 days and are affected by several factors including moisture and temperature. Finally, tebuthiuron apphed to rangeland has been shown to be phytotoxic after 615 days, and the estimated time for total dissipation of the herbicide is from 2.9 to 7.2 years (426). 

HAs have been issued for bromacil, diuron, and fluometuron no occurrence data are available for tebuthiuron or terbacd (295). Chloroxuron [1982-47-4] fenuronTCA [4482-55-7] andnorea [18530-56-8] also are urea herbicides. 

Methyl acetoacetate (MAA) and ethyl acetoacetate (EAA) are the most widely used esters they are found ia the pharmaceutical, agricultural, and allied industries. Both esters are used extensively as amine protecting agents ia the manufacture of antibiotics and synthetic sweeteners (Dane Salts) (147). Principal outiets for MAA are the manufacture of the organophosphoms insecticide dia2inon [33341-5] (148,149) and the uracil herbicides bromacil [31440-9] and terbacil [5902-51-2] (150,151) (see Insect conztiol technology Herbicides). 

In 1962, bromacil (5-bromo-3-s-butyl-6-methyluracil 1047 R = Bu ), its homologue (isocil 1047 R = Pr ) and related iV-alkyluracils were shown to have valuable selective phytotoxic properties and vitually no mammalian toxicity. Thus, bromacil achieves a complete kill of most unwanted broad-leaf annuals or perennials along with some grasses... 

Australia and United Kingdom, 142 Bromacil, 27 Bromadiolone, 27 Bromine, 27... 

C. Lipschitz, H. Iith, G. J. de Jong, U. A. Th Brinkman and R. W. Frei, Trace emich-ment of pyrimidine nucleobases, 5-fluoro-uracil and bromacil on a silver-loaded tliiol stationaty phase with on-line reversed-phase high-perfomance liquid cliromatography , J. Chromatogr. 471 321-334 (1989). 

J. V. Sancho, C. Hidalgo and P. Hernandez, Direct determination of bromacil and diuron residues in environmental water samples by coupled-column liquid cliromatog-raphy and large-volume injection , 7. Chromatogr. 761 322-326 (1997). 

The effects of water temperature and pesticide concentration on pesticide recoveries were tested by Moye et al The pesticides included alachlor, atrazine, bromacil, chlorothalonil, chloropyrifos, diazinon, endosulfan, simazine and trifluralin. Temperatures of 5,25,45 and 65 °C were tested and concentrations of 0.1,1.0 and 10 pgL were used. Water temperature had a pronounced effect on the recoveries whereas the concentration did not seem to have as great an effect. 

Bromacil (5-bromo-3-sec-butyl-6-methyluracil), Lenacil (3-cyclohexyl-5,6-trimethyleneuracil) and Terbacil (5-chloro-3-tertbutyl-6-methyluracil) herbicides... 

Bromacil residues in soils. The procedure uses relatively large volumes of solvents and extracts require a column chromatographic clean-up. 

Ammonia, see Acetonitrile, Acrylonitrile, see Atrazine. Bromacil. Bromoxvnil. Carbaryl, Chlorp3n-ifos, Dicamba. EPTC. Ethylamine, Ethylenimine, Glvnhosate. Linuron. 4-Nitrophenol, Parathion, Picloram. Pyridine, Trifluralin Ammonium acetate, see Acetonitrile Amylene, see Chloroform, Methylene chloride Aniline, see Diuron, Nitrobenzene, Nanronamide. 

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