Bensulfuron-methyl

There are several commercially available sulfonylurea herbicides that contain a 2-pyrimidine group <2006H(68)561>. These compounds, which function by inhibition of acetolactate synthase (ALS), an enzyme involved in the early stage of branched-chain amino acid synthesis, include sulfometuron-methyl 1095, primisulfuron-methyl 1096, chlorimuron-ethyl 1097, bensulfuron-methyl 1098, ethoxysulfuron 1099, nicosulfuron 1100, and pyrazosulfuron-ethyl 1101. Related nonsulfonylureas include the sulfide pyrftalid 1102 and the ether pyriminobac-methyl 1103. 

Si, Y., Zhou, J., Chen, H., Zhou, D., and Yue, Y. (2004). Effects of humic substances on photodegradation of bensulfuron-methyl on dry soil surfaces. Chemosphere 56, 967-972. Siesler, H. W., Ozaki,Y., Kawata, S., and Heise,H. M., editors. (2002). Near-Infrared Spectroscopy Principles, Instruments, Applications, Wilcy-VCI I, Wcinhcim. 

Wang, G., J. Yuan, K. Matsumoto, et al. 2001. Homogeneous time-resolved fluoroimmunoassay of bensulfuron-methyl by using terbium fluorescence energy transfer. Talanta 55 1119-1125. 

Benoxacor heterocyclic nitrogen, benzoxazine, amide Bensulfuron-methyl sulfonyl urea... 

A typical thermospray ionization mass spectrum for a sulfonylurea contains a weak protonated molecular ion and three to four characteristic fragment ions. Figure 2 shows the thermospray positive ion mass spectrum for HARMONY. The spectrum contains a protonated molecular ion at m/z 388, the sulfonamide ammonium adduct ion at m/z 239 and the protonated triazine urea fragment ion at m/z 184. At the same time, Figure 3 shows the positive ion thermospray mass spectrum for LONDAX. It contains the protonated pyrimidine amine at m/z 156, the protonated pyrimidine urea is at m/z 199 and the sulfonamide ammonium adduct ion at m/z 247. LONDAX (bensulfuron methyl) is a sulfonylurea rice herbicide and it elutes between EXPRESS and CLASSIC if we use the LC conditions outlined in Figure 1. HARMONY and LONDAX thermospray spectra were generated with the thermospray vaporizer tip temperature at 150°C and the source block temperature at 320°C. 

Bensulfuron-methyl a(4,6-Dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-o-toluic acid 410.4 5.2 0.12 28 to 140 n.f. 

The herbicide with the trade name Sanbird is able to control both annual and perennial weeds in paddy fields [5] with application rates of 3-4 kg ha . As a very selective herbicide in rice it was a good innovation for the Japanese rice market. This product reached peak sales in Japan in 1986 with 650000 ha (28.6% market share) [6]. This declined with the introduction of sulfonylurea herbicides such as bensulfuron-methyl in the year 1987. In 2005 Sanbird was only used on 101 200 ha (5.9% market share) in Japan [7]. 

Fentrazamide products such as a plus bensulfuron-methyl (Innova ), a plus pyrazosulfuron-ethyl (Doublestar ) and a plus imazosulfuron (Leading ) provide... 

The heterocyclic intermediates for bensulfuron methyl and chlorimuron methyl are prepared from 2-amino-4,6-dichloropyrimidine (XVII) (Equation 14). This intermediate was prepared by the reaction of dimethyl malonate and guani ne carbonate to yield 2-amino-4,6-dihydroxypyrimidine which is converted to the dichloro compound by phosporus oxychloride. Treatment of the dichloro intermediate with sodium methoxide and methanol gave the dimethoxy intermediate (XVin) for bensulfuron methyl, whereas with potassium carbonate and methanol the product is the 4-chloro-6-methoxy intermediate (XIX) for chlorimuron methyl. 

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