title: Synthetic Protocol for AFCS: A Biologically Active Fluorescent Castasterone Analog Conjugated to an Alexa Fluor 647 Dye.
abstract: Synthetic derivatization of hormonally active brassinosteroids (BRs) can provide useful small molecule tools to probe BR signaling pathways, such as fluorescent analogs. However, most biologically active BRs are not suitable for direct chemical conjugation techniques because their derivatization typically requires extensive synthetic work and chemistry expertise. Here, we describe an operationally simple, two-step procedure to prepare and purify an Alexa Fluor 647-castasterone (AFCS) from commercially available materials. The reported strategy is also amenable to the introduction of various other amine-based labeling groups.
authors.affiliation: Laboratory for Organic Synthesis, Department of Organic and Macromolecular Chemistry, Ghent University, 9000, Gent, Belgium. johan.winne@ugent.be.
authors.forename: Johan M
authors.initials: JM
authors.lastname: Winne
authors.affiliation: Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.|Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK.
authors.forename: Niloufer G
authors.initials: NG
authors.lastname: Irani
authors.affiliation: Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, 9000, Gent, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Van den Begin
authors.affiliation: Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, 9000, Gent, Belgium.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Madder
mesh_terms: D060406:Brassinosteroids / Q000138:chemical synthesis*; D002232:Carbocyanines / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D002777:Cholestanols / Q000737:chemistry*; D002855:Chromatography, Thin Layer / Q000379:methods; D005456:Fluorescent Dyes / Q000737:chemistry; D010091:Oximes / Q000737:chemistry*; D010937:Plant Growth Regulators / Q000138:chemical synthesis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013194:Staining and Labeling / Q000379:methods
chemical_list: C569686:Alexa Fluor 647; D060406:Brassinosteroids; D002232:Carbocyanines; D002777:Cholestanols; D005456:Fluorescent Dyes; D010091:Oximes; D010937:Plant Growth Regulators; C083545:castasterone
keywords: Brassinosteroids; Castasterone; Fluorescent labeling; Oxime conjugation; Steroid hormones