title: New branching inhibitors and their potential as strigolactone mimics in rice.
abstract: Strigolactones (SLs) are rhizosphere communication chemicals. Recent studies of highly branched mutants revealed that SL or its metabolites work as a phytohormone to inhibit shoot branching. When SLs are exogenously applied to the rice d10-1 mutant that has a highly branched phenotype caused by a defect in the SL biosynthesis gene (CCD8), they inhibit tiller bud outgrowth (branching in rice) of the mutant. We focused our attention on the SL function as a phytohormone and tried to find new chemicals mimicking the hormonal action of SL by screening chemicals that inhibit branching of rice d10-1 mutant. Fortunately, we found 5-(4-chlorophenoxy)-3-methylfuran-2(5H)-one (3a) as a new chemical possessing SL-like activity against the rice d10-1 mutant. Then, we prepared several derivatives of 3a (3b-3k) to examine their ability to inhibit shoot branching of rice d10-1. These derivatives were synthesized by a one-pot coupling reaction between phenols and halo butenolide to give 5-phenoxy 3-methylfuran-2(5H)-one (3) derivatives, which possess a common substructure with SLs. Some of the derivatives showed SL-like activity more potently than GR24, a typical SL derivative, in a rice assay. As SLs also show activity by inducing seed germination of root parasitic plants, the induction activity of these derivatives was also evaluated. Here we report the structure-activity relationships of these compounds.
authors: Graduate School of Agriculture and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan.
authors: Kosuke
authors: K
authors: Fukui
authors: Shinsaku
authors: S
authors: Ito
authors: Kotomi
authors: K
authors: Ueno
authors: Shinjiro
authors: S
authors: Yamaguchi
authors: Junko
authors: J
authors: Kyozuka
authors: Tadao
authors: T
authors: Asami
mesh_terms: D004305:Dose-Response Relationship, Drug; D005663:Furans / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018525:Germination / Q000187:drug effects; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018716:Molecular Mimicry; D015394:Molecular Structure; D031672:Orobanche / Q000187:drug effects / Q000254:growth & development; D012275:Oryza / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D010641:Phenotype; D018520:Plant Shoots / Q000187:drug effects* / Q000254:growth & development; D012639:Seeds / Q000187:drug effects / Q000254:growth & development; D013237:Stereoisomerism; D034362:Striga / Q000187:drug effects / Q000254:growth & development; D013329:Structure-Activity Relationship
chemical_list: D005663:Furans; D007783:Lactones