Synthesis and effect on seed germination and growth of 5-(thio) phenol-3-methylfuran-2(5H)-one analogues as strigolactone mimics.

Background: Phytohormones regulate plant growth, development, and stress responses. Strigolactones are a class of phytohormones that have attracted significant scientific interest because of their multifunctional roles in plant biology and ecological interactions.

Results: In this study, 34 strigolactone mimics were efficiently synthesized by substituting pre-synthesized 5-chloro-3-methylfuran-2(5H)-one with phenolics and benzenethiols. Most of the chemicals showed seed germination-promoting activities on corn, sorghum, soybean, and sunflower seeds. At a concentration of 100 mg/L, 3 s and 4 h showed a promotion rate of 56% and 63% on corn bud growth and 50% and 62% on sorghum root growth, respectively. The promotion rates of 3 s and 4 h on corn, sorghum, soybean, and sunflower root growth ranged between 35-48% and 46-71%, respectively. The effect on germination of the target compound exhibited a dose-dependent trend, increasing within the range of 0.01-10 mg/L and decreasing within the range of 10-100 mg/L. Optimal promotion rates for corn root and shoot growth at 3 s and 4 h were achieved at a concentration of 10 mg/L. 3 s and 4 h regulated the content of the abscisic acid, auxin, cytokinin, and gibberellin to promote plant germination. The binding energy of GR24 docking with strigolactone receptor proteins derived from Arabidopsis (AtD14) was -7.30 kcal/mol, while 3 s and 4 h were -7.96 and -8.05 kcal/mol, respectively.

Conclusions: The structure-activity relationships of 34 novel strigolactone mimics and docking simulations provided structural optimization strategies for designing new strigolactone mimics as plant growth regulators. © 2025 Society of Chemical Industry.