Study On Synthesis, Bio-activity And SAR Of Isoindoline-1, 3-dione Derivatives

In the 21^th century, pesticide must have the characteristics of high effect, safety, low cost and environmentally-friend. Protoporphyriinogen oxidase (protox) inhibitors are light-dependent herbicides, which will be found a wider application because their unique herbicidal mechanism can ensure very good selectivity between human animals and plants.To overcome limitations of some lead compounds in physical property and biological activity, some novel compounds with latent protox inhibiting activity were designed by choosing commercial protox inhibitor flumioxazin and other herbicides as lead compounds based on pesticide molecular design technologies, such as activity sub-structure connecting, and bioisosteric replacement; 9 kinds, 85 novel 2-substituted phenyl isoindoline-dione (SPIIDO) derivatives were prepared by the traditional organic synthesis methods and purification technique for target products utilizing polymer-supported scavenger reagent, and these compounds could be divided into 4 series: benzoxazin-substituted isoindolinediones, isoindoline- dione-substituted benzoxazine carboxyl esters, N- isoindoline- dione-substituted phenyl acylamines and N- isoindolinedione- substituted phenyl ureas. Their structures were confirmed by ¹H NMR, IR, mass spectroscopy and elemental analysis. The first introduction of carboxyl ester group into isoindolinedione-substituted benzoxazinone derivatives and that of N, N-um-symmetrical urea group or benzylurea group into the 5-position of benzene cycle of SPIIDO derivatives expanded the chemical structural types of protox inhibitors.The bioassays of preliminary herbicidal activity were carried out according to the standard operation procedure of pesticide bioassay, and the results showed that many compounds exhibited higher inhibiting protox activity. For example, one compound of benzoxazin-substituted isoindolinedione derivatives had comparable herbicidal activity and crop safety as flumioxazin and B2055, three compounds of isoindolinedione- substituted benzoxazine carboxyl ester derivatives possed more than 80% herbicidal efficiency at 75 g ai/ha in both pre- and post-emergence treatments against both dicotyledon weeds such as Abutilon theophrasti Medic, Chenopodiun album L., Amaranthus retroflexus L. and monocotyledon weeds such as Digitaria sanguinalis L., Echinochloa crus-galli L., Setaria viridis L., two...