Synthesis And Acaricidal Activity Of The C=N Double Bound Modifications Of 2-aryl-3,4-Dihydroisoquinoliniums

Quaternary benzo phenanthridine alkaloids (QBAs) is a kind of isoquinoline alkaloid, like chelerythrine and sanguinarine, which have good insecticidal activity, but its low content and less species make its development and utilization limited. I synthesized the double bond modifications of 2-aryl-3, 4-dihydroisoquinolinium bromides (ADHIQs) based on the study of ADHIQs and 1- methoxy-2-phenyl-1, 2, 3, 4- tetrahydroisoquinoline’s synthesis and acaricidal activity, which is excepted to find high efficiency, low concentration, small environment pollution caricidal agent and contributing for Chinese veterinary medicine research.Firstly, I improved the synthesis method of the key precursors-Isochroman, then synthetized ADHIQs based on the established method, eventually synthetized the double bond modifications of ADHIQs from ADHIQs though a building simple method, and investigated its insecticidal activities to P. communis cuniculi.The results showed that the improved synthetical method of Isochroman reduced the formation of impurities, and the yield increased by about 8%. Thirteen in fifteen final products were new compounds, checked with ESI- MS,IR,1H NMR, 13C NMRå'ŒX-raysingle crystal diffraction before though SciFinder Scholar’s checking, eleven in thirteen were 1,1’-oxybis(2-aryl-1,2,3,4-tetrahydroisoquinoline), respectively two other were 1-oxethyl-(2-(4-(trifluoromethyl)pheny)-1,2,3,4-tetrahydeoisoquinoline) and 2-(2-hydro xyphenyl)-3,4-dihydroisoquinolin-1(2H)-one. The results of acaricidal activity showd that two modifications of 2-phenyl-3,4-dihydroisoquinoliniums and two compounds of 1, 1’-oxybis(2-aryl-1,2,3,4- tetrahydroisoquinoline) had lethallty rates more than 50%, and 1, 1’-oxybis(2-(3-chlorophenyl)-1,2,3,4- tetrahydroisoquinoline) showed the highest lethallty rates, which reached 76% in concentration 0.2 mg?mL-1, 20% more than Ivermectin. Compared with ADHIQs’ acaricidal activity, the acaricidal activity of 2-aryl-1,2,3, 4-tetrahydroisoquinoline substituted by methoxy, oxethyl, propoxy or isopropoxy on C1 position were better, and oxethyl substituendum was the best one in them. But the activity of 1,1’-oxybis(2-aryl-1,2,3,4-tetrahydroisoquinoline),2-(2-hydroxyphenyl)-3,4-dihydroisoquinolin-1(2H)-one and 1-oxethyl(2-(4-(trifluoromethyl)pheny)-1,2,3,4-tetrahydeoisoquinoline) decreased quickly in concentration from 0.2 mg?mL-1 to 0.4 mg?mL-1, especially the compounds substituted by trifluoromethyl or hydroxylsubstitute on benzene ring.