Table 2.
Overview of small molecules interfering with BR biosynthesis, perception or signaling.
| Compound | Type | Commercially Available | IC50 in µM 1 | Target; Kd in µM 2 |
|---|---|---|---|---|
| BRZ | Triazole | Yes | 0.58 ± 0.38 At [170]; 0.73 ± 0.13 At L 5d [235]; 0.77 At D 6 d [217] | DWF4; 1.05 [174] |
| BRZ2001 | Triazole | No | 0.55 At [219]; 0.33 At D 6 d [217] | DWF4 [221] |
| BRZ220 | Triazole | No | 0.61 ± 0.14 At [169] | DWF4 [168] |
| (2S,4R)-BRZ220 | Triazole | No | 0.01 C L 8 d [224]; 1.21 At D 5d [168] | DWF4; 0.22 [168] |
| YCZ-18 | Triazole | No | 0.10 ± 0.03 At [170]; 0.13 ± 0.03 At [169] | CYP90D1; 0.79 [73] |
| YCZ-14 | Triazole | No | 0.12 ± 0.04 At L 5 d [235] | CYP90D1 (?) |
| (2S,4R)-YCZ-2013 | Triazole | No | 0.024 ± 0.003 3 At [236] | CYP90D1 (?) |
| YCZ-FL | Triazole | No | 1.56 At D 5 d [234] | CYP90D1 (?) |
| Yucaizol | Triazole | No | 0.8 R L 10 d [163]; 0.045 ± 0.003 At D 5 d [169] | CYP90D1 (?) |
| Propiconazole | Triazole | Yes | - | CYP90D1; 0.76 [75] |
| Triadimefon | Triazole | Yes | Approximately 3 4 [175] | DWF4; 2.5 [175] |
| Imazalil | Imidazole | Yes | 3.44 At D 6 d [217] | - |
| Fenarimol | Pyrimidine | Yes | 1.8 ± 02 At D 5 d [74] | CYP90D1; 0.79 [74] |
| DPP4 | Pyrimidine | No | - | CYP90D1 (?) |
| 4-MA | Steroid | No | - | DET2; Ki 0.3 [76,77] |
| Finasteride | Steroid | Yes | - | DET2 [76] |
| AFA76 | Benzo[c]quinolizin-3-one | No | - | DET2 [76] |
| Spironolactone | Steroid | Yes | Approximately 30 5 [285] | - |
| Brassinopride | Amide | No | 17 At D [298] | - |
| Voriconazole | Triazole | Yes | 0.083 ± 0.019 C L 7 d 6 | CYP51 [78] |
| Lithium chloride | Salt | Yes | - | BIN2 [132,138] |
| Brassinolide-2,3-acetonide | Steroid | No | - | BRI1 [310] |
| Compounds 1, 2, 4 and 6 | Phenylfuran | No | Comp. 1, ID50: 5 nmol/plant RLI; Comp. 2, ID50: 3.2 nmol/plant RLI [313] | BRI1 [313,314] |
| Compound 14 7 | - | No | ID50: 0.63 nmol/plant RLI [313] | BRI1 [313] |
| NSBR1 | - | No | ED50: 0.8 nmol/plant RLI [312] | BRI1 [312] |
| Bikinin | Pyridine | Yes | EC50: 23.3 At L 6 d [177] | BIN2; 241 [70] |
| Methyliodobikinin | Pyridine | No | EC50: 6.8 At L 6 d [177] | BIN2 [177] |
| Brazide | Thiazole | No | - | BIN2 (?) |
| KM-01 | Natural compound | No | - | - |
| F1874-108 | - | No | - | BIN2 (?) [341] |
1Abbreviations: IC50, half maximal inhibitory concentration; ID50, half maximal inhibitory dose; EC50, half maximal effective concentration; ED50, half maximal effective dose; At, A. thaliana hypocotyl elongation assay; C, cress hypocotyl elongation assay; R, rice seedling retardation assay; RLI, rice lamina inclination assay; D, grown in the dark; L, grown in long day conditions; d, grown for the indicated number of days. BIN2 means BIN2 and its homologues. 2 A question mark (?) indicates that the target is expected but experimental evidence is lacking. Abbreviations: Kd, dissociation constant; Ki, inhibition constant. 3 The (2S,4R) enantiomer has approximately the same activity. 4 Estimated from Figure 5 of the cited reference. 5 Estimated from Figure 3 of the cited reference. 6 This study (see Supplementary File S1).7 Benzene-1,4-diyldimethanediyl di-3-ethyl-5-methyl-1,2-oxazole-4-carboxylate.