(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one | CAS 1391913-90-8

(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one is a xanthene-derived fluorescent dye designed for strong light absorption and emission in fluorescence imaging workflows, with a spirocyclic framework that supports compact, conjugation-friendly dye behavior in labeled constructs. The diethylamino substituents provide a typical donor character for bright fluorescence, while the amide-bearing side chain supports stable incorporation into biomolecule and polymer labeling strategies used in chemical biology and microscopy-based assays. In practice, this dye is selected when researchers need a robust fluorophore for building fluorescent conjugates, reference standards, and signal reporters compatible with common fluorescence readout platforms.

1. Fluorescent Labeling Conjugates

(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one is used as a fluorescent labeling component for preparing dye-tagged biomolecule conjugates in protein and peptide labeling studies. Chemical biology groups incorporate this fluorophore into purified conjugates for tracking binding, monitoring localization in fixed samples, and visualizing biomolecular interactions under fluorescence microscopy. The dye's xanthene core supports high-contrast imaging in labeled constructs, making it a practical choice for researchers building fluorescent reagents for assay development and imaging reagent libraries.

2. Fluorescence Microscopy Staining

(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one supports fluorescence microscopy workflows where a bright, organic fluorophore is required for cellular or biomaterial visualization. Microscopy users apply this dye in staining and labeling formats for tracking fluorescently tagged targets on substrates, within labeled biomaterials, or in imaging studies where consistent dye performance across staining batches is important. Researchers often select this fluorophore when they want a stable, dye-based signal that integrates cleanly into established fluorescence imaging pipelines and downstream quantitative image analysis.

3. FRET Pair Construction

(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one is frequently incorporated into FRET-based experimental designs as a donor fluorophore in fluorescence resonance energy transfer constructs. In these applications, the dye is used to build donor-acceptor labeling pairs for proximity-dependent readouts in molecular imaging and biomolecular interaction studies. Researchers use such FRET labeling reagents to generate distance-sensitive fluorescence responses in labeled systems, including engineered conjugates and assay formats where donor emission attenuation upon acceptor coupling provides the primary signal.

4. Fluorescence Bioassay Reporter

(E)3',6'-bis(diethylamino)-2-(4-oxopent-2-en-2-ylamino)spiro〔isoindoline-1,9'-xanthen〕-3-one is applied as a fluorescent reporter in fluorescence-based bioassay development where a dye with strong emission is required for readout. Assay development teams incorporate the dye into labeled detection reagents, calibration standards, or fluorescence-tagged components used to monitor binding events, workflow performance, or reagent integrity in plate-based measurements. This fluorophore is particularly useful in reagent engineering contexts where consistent fluorescence intensity from the labeled construct supports routine assay execution and quantitative comparison across experimental conditions.