Synthesis And Herbicidal Activity Of Novel Benzoxazine Derivatves And Pyrimidinamine Derivatves

Protoporhyrinogen oxidase (protox) inhibitor is one of the most popular fields in pesticidal chemistry. The successful development of protox inhibitors has made herbicide go into a new age. Protox inhibitors act on biological target enzyme inhibitor with high efficiency, high selectivity, short residual time, and they are safe to creature excluding the target and friendly to environment. Protox inhibitors containing 2H-1,4-benzoxazine-3-one group have been paid more and more attentions for their excellent herbicidal activity. The typical commercial herbicide is flumioxazin which had been developed by Sumitomo Chemical Company, Ltd., Osaka, Japan.The new researching development of protox inhibitors were reviewed in this article. The current researching situation, effective mechanism and QSAR were introduced in details. The synthesis routes of 2H-1,4-benzoxazine derivates were introduced too. Taken the flumioxazin as the lead compound, 27 new compounds were synthesized, and the other 9 new compounds were also synthesized by active sub-structure linkage theory.All synthesized compounds can be divided into three series as fellows: (â… )2-substitued-N-(7-fluoro-2,4-disubstitued-3-oxo-3,4-dihydro-2H-benz[b][1,4] oxazin-6-yl) Acetamide(â…¡)N- (7-fluoro-2,4-disubstitued-3-oxo-3,4-dihydro-2H-benz [b][1,4] oxazin-6-yl) -N', N'-disubstitued urea(â…¢) 2-substitued-N-(4,6-disubstitued-pyrimide-2-yl) Acetamide Synthesis methods for each intermediates and target compounds were studied, and the structure of the prepared compounds were confirmed by IR, ~1H NMR, LC/MS. The crystal structure of compoundâ… h had been discussed.Compoundsâ… andâ…¢were tested at 75 g a.i/hm~2 for herbicidal activity. It was found that a number of the compounds C exhibited different control efficacy. Compoud I h showed control efficacy more than 90% against Setaria viridis, Echinochloa crus-galli. Chenopodium album. Amaranthus spinosus.