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(5 H )‐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.