title: meso-Ester and carboxylic acid substituted BODIPYs with far-red and near-infrared emission for bioimaging applications.
abstract: A series of meso-ester-substituted BODIPY derivatives 1-6 are synthesized and characterized. In particular, dyes functionalized with oligo(ethylene glycol) ether styryl or naphthalene vinylene groups at the α positions of the BODIPY core (3-6) become partially soluble in water, and their absorptions and emissions are located in the far-red or near-infrared region. Three synthetic approaches are attempted to access the meso-carboxylic acid (COOH)-substituted BODIPYs 7 and 8 from the meso-ester-substituted BODIPYs. Two feasible synthetic routes are developed successfully, including one short route with only three steps. The meso-COOH-substituted BODIPY 7 is completely soluble in pure water, and its fluorescence maximum reaches around 650 nm with a fluorescence quantum yield of up to 15 %. Time-dependent density functional theory calculations are conducted to understand the structure-optical properties relationship, and it is revealed that the Stokes shift is dependent mainly on the geometric change from the ground state to the first excited singlet state. Furthermore, cell staining tests demonstrate that the meso-ester-substituted BODIPYs (1 and 3-6) and one of the meso-COOH-substituted BODIPYs (8) are very membrane-permeable. These features make these meso-ester- and meso-COOH-substituted BODIPY dyes attractive for bioimaging and biolabeling applications in living cells.
authors: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543 (Singapore), Fax: (+65) 6779-1691; NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, 02-01, Singapore 117411 (Singapore).
authors: Yong
authors: Y
authors: Ni
authors: Lintao
authors: L
authors: Zeng
authors: Nam-Young
authors: NY
authors: Kang
authors: Kuo-Wei
authors: KW
authors: Huang
authors: Liang
authors: L
authors: Wang
authors: Zebing
authors: Z
authors: Zeng
authors: Young-Tae
authors: YT
authors: Chang
authors: Jishan
authors: J
authors: Wu
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002460:Cell Line; D018360:Crystallography, X-Ray; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D010539:Permeability; D019265:Spectroscopy, Near-Infrared
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D002264:Carboxylic Acids; D005456:Fluorescent Dyes
keywords: BODIPY; bioimaging; dyes; fluorescent probes; membrane permeability; near-infrared