Electrochemical Synthesis of Isoquinoline Sulfone Compounds and Study of their Inhibition of Acetolactate Synthase Enzyme Activity

Abstract Both of sulfone compounds and isoqunoline derivatives are important compounds. In this paper, Isoquinoline C1 and C3 Sulfone compounds have been synthesized by electrochemical means using isoquinoline N‐Oxides and some sodium benzenesulfinate as reactants, inexpensive and easily available sodium iodide as electrolytes, and a mixture of acetonitrile, water and acetic acid as reaction solvents. By using the method, a series of isoquinoline sulfone compounds have been synthesized in high yields. The reaction does not need oxidants and catalysts, and the reaction conditions are mild, environmentally friendly, efficient and suitable. In addition, we also carried out ALS enzyme inhibition experiments on the synthesized isoquinoline sulfone compounds, six of the isoquinoline sulfone compounds synthesized herein were found to inhibit ALS enzyme at a high rate, four of them inhibited ALS enzyme at a rate comparable to that of the commercialized herbicides Halosulfuron and Broadstrike, and the other two compounds also inhibited ALS enzyme at a rate higher than that of Halosulfuron and Broadstrike. Therefore, it is possible to find lead compounds with good herbicidal activity potential from these 6 compounds.