title: The structure-activity relationship in herbicidal monosubstituted sulfonylureas.
abstract: BACKGROUND
  The herbicide sulfonylurea (SU) belongs to one of the most important class of herbicides worldwide. It is well known for its ecofriendly, extreme low toxicity towards mammals and ultralow dosage application. The original inventor, G Levitt, set out structure-activity relationship (SAR) guidelines for SU structural design to attain superhigh bioactivity. A new approach to SU molecular design has been developed.
  
  
  RESULTS
  After the analysis of scores of SU products by X-ray diffraction methodology and after greenhouse herbicidal screening of 900 novel SU structures synthesised in the authors' laboratory, it was found that several SU structures containing a monosubstituted pyrimidine moiety retain excellent herbicidal characteristics, which has led to partial revision of the Levitt guidelines.
  
  
  CONCLUSIONS
  Among the novel SU molecules, monosulfuron and monosulfuron-ester have been developed into two new herbicides that have been officially approved for field application and applied in millet and wheat fields in China. A systematic structural study of the new substrate-target complex and the relative mode of action in comparison with conventional SU has been carried out. A new mode of action has been postulated.
authors: National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, China. nkzml@vip.163.com
authors: Zheng-Ming
authors: ZM
authors: Li
authors: Yi
authors: Y
authors: Ma
authors: Luke
authors: L
authors: Guddat
authors: Pei-Quan
authors: PQ
authors: Cheng
authors: Jian-Guo
authors: JG
authors: Wang
authors: Siew S
authors: SS
authors: Pang
authors: Yu-Hui
authors: YH
authors: Dong
authors: Cheng-Ming
authors: CM
authors: Lai
authors: Ling-Xiu
authors: LX
authors: Wang
authors: Guo-Feng
authors: GF
authors: Jia
authors: Yong-Hong
authors: YH
authors: Li
authors: Su-Hua
authors: SH
authors: Wang
authors: Jie
authors: J
authors: Liu
authors: Wei-Guang
authors: WG
authors: Zhao
authors: Bao-Lei
authors: BL
authors: Wang
mesh_terms: D001937:Brassica / Q000187:drug effects; D006540:Herbicides / Q000737:chemistry* / Q000494:pharmacology*; D008958:Models, Molecular; D015394:Molecular Structure; D013329:Structure-Activity Relationship; D013453:Sulfonylurea Compounds / Q000737:chemistry* / Q000494:pharmacology*; D014961:X-Ray Diffraction
chemical_list: D006540:Herbicides; D013453:Sulfonylurea Compounds