Synthesis and Phytotoxic Evaluation of 3-Indolylglycine Derivatives as New Natural-Like Herbicides

A novel class of potential herbicides, 3-indolylglycines were synthesized using an effective, green and rapid approach via multicomponent reaction (aza-Friedel-Crafts) between indoles, aldehydes and anilines in a water/sodium dodecyl sulfate system. The main advantages of this methodology are ease of handling, scalable to gram scale and a metal-free approach. The reaction is compatible with a variety of functional groups, obtaining the desired products in moderate to excellent yields. The biological activity of the 3-indolylglycines was evaluated, and it was found that these compounds interfere with the germination and radicle growth of Lactuca sativa, mainly the compound 4k.