Synthesis and Herbicidal Activity of O,O-Dialkyl N-[2-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-yloxy)benzoxyl]-1-a mino-1-substitutedbenzyl Phosphonates

摘要

A series of novel 1.2,4-triazolo[1,5-a]pyrimidine derivatives containing an a-amino phosphonate moiety 5 were designed and synthesized by the multi-step reactions. Their structures were clearly confirmed by spectroscopic data (IR, H-1 NMR, P-31 NMR, MS) and elemental analysis, compound 5b was further determined by X-ray diffraction crystallography. The results of preliminary bioassay indicated that some of the title compounds 5 possessed moderate herbicidal activities against dicotyledonous plants (Brassica campestris L) at the concentration of 100 mg/L. For example, compound 5i possessed 92.0% inhibitory activity against B. campestris L and showed better activity than that of the commercialized herbicide Bispyribac-sodium; however, compounds 5 displayed weak herbicidal activity at the concentration of 10 mg/L.