The Sanya Institute of Nanjing Agricultural University, Sanya, Hainan 572000, P. R. China.
College of Plant Protection, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
J Org Chem. 2024 Sep 20;89(18):13359-13366. doi: 10.1021/acs.joc.4c01514. Epub 2024 Sep 6.
Indole alkaloids are privileged secondary metabolites, and their production may be achieved by the microbial biotransformation of tryptophan analogues. By feeding 1-methyl-L-tryptophan (1-MT) into the culture of endophytic GGY-3, six novel (-) and seven known indole alkaloids (-) were generated. Their structures were elucidated by means of NMR spectroscopy, experimental electronic circular dichroism (ECD) spectra, and X-ray crystallography analysis. A Friedel-Crafts reaction was proposed as the key reaction responsible for the formation of the new compounds. Racemates and were separated into isomers by chiral HPLC, with their absolute configurations determined by X-ray and ECD calculation. Compounds , , and display good herbicidal activity against dicotyledon weed , of which and exhibited 88.50% and 100% inhibition rates on the radicle at 200 μg/mL, respectively, a similar effect compared to the positive control penoxsulam.
吲哚生物碱是一种重要的次级代谢产物，其可以通过色氨酸类似物的微生物生物转化来获得。通过向内生菌 GGY-3 的培养物中添加 1-甲基-L-色氨酸（1-MT），生成了六个新的（-）和七个已知的吲哚生物碱（-）。通过核磁共振波谱、实验电子圆二色性（ECD）光谱和 X 射线晶体学分析阐明了它们的结构。提出了 Friedel-Crafts 反应作为形成新化合物的关键反应。通过手性 HPLC 将外消旋体和分离成异构体，并通过 X 射线和 ECD 计算确定其绝对构型。化合物、和对双子叶杂草表现出良好的除草活性，其中和在 200μg/mL 时对胚根的抑制率分别达到 88.50%和 100%，与阳性对照吡氟酰草胺的效果相当。
