title: Synthesis and herbicidal activity of isoindoline-1,3-dione substituted benzoxazinone derivatives containing a carboxylic ester group.
abstract: A carboxylic ester group was introduced to three series of isoindolinedione substituted benzoxazinone derivatives. Some of these analogues exhibited good herbicidal activities, and the injury symptoms against weeds included leaf cupping, crinkling, bronzing, and necrosis, typical of protox inhibitor herbicides. Structurally, they were classified as Chemical Group A (4-carboxylic ester group-6-isoindolinyl-benzoxazinones), B (4-carboxylic ester group-7-isoindolinyl-benzoxazinones), and C (4-carboxylic ester group-6- tetrahydroisoindolinyl-benzoxazinones). All of the tested compounds were structurally confirmed by (1)H NMR, IR, mass spectroscopy, and elemental analysis. Preliminary bioassay data of these three classes of compounds showed that, in general, the order of the herbicidal effectiveness is C > A > B. Several of the lead compounds, for example, C10 (methyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-2-methyl-3-oxo-2H-benzo[b][1,4] oxazin-4(3H)-yl) propano-ate), C12 (ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-2- methyl-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) propanoate), and C13 (ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-2-methyl-3-oxo-2H-benzo-[b][1,4]oxazin-4(3H)-yl) butanoate), exhibited greater than 80% control at 75 g a.i./ha in both pre- and postemergence treatments against dicotyledonous weeds, such as Abutilon theophrasti Medic, Chenopodium album L., and Amaranthus ascendens L., and monocotyledon weeds, such as Digitaria sanguinalis L., Echinochloa crus-galli L., and Setaria viridis L. On the basis of advanced screening tests and crop selectivity, compounds C10, C12, and C13 are safer to crops than flumioxazin. Compounds C10, C12, and C13 are potent to develop as pre-emergent herbicides used in peanut, soybean, maize, and cotton fields.
authors.affiliation: National Engineering Research Center for Agrochemicals, Hunan Research Institute of Chemical Industry, Changsha 410007, People's Republic of China. huang-mz@163.com
authors.forename: Ming-Zhi
authors.initials: MZ
authors.lastname: Huang
authors.forename: Fei-Xian
authors.initials: FX
authors.lastname: Luo
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Mo
authors.forename: Ye-Guo
authors.initials: YG
authors.lastname: Ren
authors.forename: Xiao-Guang
authors.initials: XG
authors.lastname: Wang
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Ou
authors.forename: Man-Xiang
authors.initials: MX
authors.lastname: Lei
authors.forename: Ai-Ping
authors.initials: AP
authors.lastname: Liu
authors.forename: Lu
authors.initials: L
authors.lastname: Huang
authors.forename: Man-Cai
authors.initials: MC
authors.lastname: Xu
mesh_terms: D006540:Herbicides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D019684:Magnoliopsida / Q000187:drug effects; D015394:Molecular Structure; D013329:Structure-Activity Relationship
chemical_list: D006540:Herbicides