Algicidal Activity of Bacillamide Alkaloids and Their Analogues against Marine and Freshwater Harmful Algae

Harmful algal blooms have become a great challenge to global aquatic ecosystems over the past decades. Given their low toxicity, high selectivity, and environment-friendly properties, the use of natural products and their analogues as algicides has proven to be particularly efficient. In the present study, algicidal activity of naturally occurring bacillamides A-C, alkaloid (1), and neobacillamide A, as well as their synthetic analogues were investigated intensively. Bioassay results showed that, relative to natural bacillamide alkaloids, aniline-derived analogue (10d) exhibited higher algicidal potential against three freshwater harmful algae Mycrocyctis aeruginosa, Scenedesmus obliquus, and Chlorella pyrenoidosa, suggesting that it could be used as a promising lead compound to develop novel algicide for controlling harmful algal blooms.