5236. Isoxaflutole

Nomenclature

CAS number: 141112-29-0
(5-Cyclopropyl-4-isoxazolyl)[2-(methylsulfonyl)-4-(trifluoromethyl)phenyl]methanone; 5-cyclopropyl-1,2-oxazol-4-yl α,α,α-trifluoro-2-mesyl-p-tolyl ketone; 5-cyclopropylisoxazol-4-yl 2-mesyl-4-trifluoromethylphenyl ketone; 5-cyclopropyl-4-(2-methanesulfonyl-4-trifluoromethylbenzoyl)isoxazole; 264-EUP-99; RPA-201772; Balance (Bayer CropSci.); Merlin (Bayer CropSci.).
C15H12F3NO4S; mol wt 359.32.
C 50.14%, H 3.37%, F 15.86%, N 3.90%, O 17.81%, S 8.92%.

Description and references

Pre-emergent herbicide designed for use in maize. Disrupts pigment biosynthesis via an inhibition of 4-hydroxyphenylpyruvate dioxygenase. Prepn: P. A. Cain et al., EP 527036 (1993 to Rhone-Poulenc). Properties and biological activity: B. M. Luscombe et al., Brighton Crop Prot. Conf. - Weeds 1995, 35. Weed control in maize: B. M. Luscombe, K. E. Pallett, Pestic. Outlook 7, 29 (1996). Mechanism of action: K. E. Pallett et al., Pestic. Sci. 50, 83 (1997). Soil persistence: J. Rouchaud et al., Bull. Environ. Contam. Toxicol. 60, 577 (1998).

Chemical structure

Properties

Off-white or pale yellow solid, mp 138-138.5° (Cain); also reported as mp 140° (Luscombe). Vapor pressure at 25°: 1×106 Pa. Soly in water: 6.2 mg/l. LD50 in rats, quails, mallard ducks (mg/kg): >5000, >2150, >2150 orally; in rabbits (mg/kg): >2000 dermally (Luscombe).

Use

Herbicide.