Trifloxysulfuron

NOMENCLATURE
Common name trifloxysulfuron (BSI, pa ISO)
IUPAC name 1-(4,6-dimethoxypyrimidin-2-yl)-3-[3-(2,2,2-trifluoroethoxy)-2-pyridylsulfonyl]urea
Chemical Abstracts name N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(2,2,2-trifluoroethoxy)-2-pyridinesulfonamide
CAS RN [199119-58-9] sodium salt; [145099-21-4] acid Development codes CGA 292230; CGA 362622 (sodium salt) (both Ciba-Geigy)

PHYSICAL CHEMISTRY
Mol. wt. 459.3 (sodium salt); 437.4 (acid) M.f. C14H14F3N5O6S Form Odourless, white to off-white powder. M.p. 170.2-177.7 °C V.p. <0.01 mPa (25 °C) KOW logP = -0.43 (pH 7, 25 °C) Henry 2.6 ?10-5 Pa m3 mol-1 (calc.) S.g./density 1.63 g/cm3 (21 °C) Solubility In water 5016 mg/l (pH 7, 25 °C). Stability Hydrolysis DT50 20 d (pH 7, 25 °C); photolysis DT50 7 h (25 °C). pKa 4.76 (20 °C)

COMMERCIALISATION
History Reported by Hudetz et al., Proc. South. Weed Sci. Soc. 53, 163-166 (2000). Under development by Syngenta AG; Patents EP-B-540697; US-A-5403814 Manufacturers Syngenta (ENVOKE)

APPLICATIONS
Biochemistry Inhibitor of acetolactate synthase
Mode of action Readily absorbed by shoots and roots and is translocated in weeds. Susceptible weeds show chlorotic symptoms within days and die within 1-3 weeks.
Uses The sodium salt is under development for post-emergence grass, sedge, and broad-leaved weed control in cotton and sugar cane. Formulation types WG. Selected tradenames: mixtures: 'Krismat' (+ ametryn) (trifloxysulfuron as sodium salt) (Bayer)

OTHER TRADENAMES
'Brawn' (Syngenta); 'Enfield''ENVOKE' (Syngenta)