Boron Dipyrrin Dyes Research Articles

Nir mono and bi 2-vinylthiophene substituted boron dipyrrin dyes: from practice to theory to further practice

Boron dipyrrin (BODIPY) family is one of the most studied collection of fluorophores, many of which are specifically designed for vital medical uses, such as cell imaging. In this research area, near-infrared absorbing and emitting compounds play the key role. Because of their long wavelength of absorption, they can be effectively excited by taking advantage of therapeutic window of human tissues. Herein we report the repeat of the synthesis of two vinylthiophene-substituted derivatives with extended π-electron systems and their computational investigation. Those dyes were prepared starting from methyl-substituted ones via addition reaction of aldehyde-containing thiophene following the literature. Obtained experimental and theoretical data will allow us to design promising tools not only for cell imaging, but also for fluorescent detection of heavy cations via coordination and possibly more.

BODIPY Dyes as Probes and Sensors to Study Amyloid-β-Related Processes.

Amyloid formation plays a major role in a number of neurodegenerative diseases, including Alzheimer’s disease. Amyloid-β peptides (Aβ) are one of the primary markers associated with this pathology. Aβ aggregates exhibit a diverse range of morphologies with distinct pathological activities. Recognition of the Aβ aggregates by using small molecule-based probes and sensors should not only enhance understanding of the underlying mechanisms of amyloid formation, but also facilitate the development of therapeutic strategies to interfere with amyloid neurotoxicity. BODIPY (boron dipyrrin) dyes are among the most versatile small molecule fluorophores. BODIPY scaffolds could be functionalized to tune their photophysical properties to the desired ranges as well as to adapt these dyes to various types of conditions and environments. Thus, BODIPY dyes could be viewed as unique platforms for the design of probes and sensors that are capable of detecting and tracking structural changes of various Aβ aggregates. This review summarizes currently available examples of BODIPY dyes that have been used to investigate conformational changes of Aβ peptides, self-assembly processes of Aβ, as well as Aβ interactions with various molecules.

Quantum-chemical study of oxophosphorus dipyrromethene (PODIPY) fluorophore coordination environment

Boron dipyrrin (BODIPY) fluorophores possess a range of excellent spectral characteristics, making their parent structure a useful scaffold for design of optically active molecules. Recently, new oxophosporus dipyrrin (PODIPY) compounds were introduced. They were shown to possess spectroscopic properties similar to those of corresponding BODIPY dyes. However, better solubility in polar solvents makes PODIPY better candidate for in vitro and in vivo fluorescent diagnostics. Here we give further insight into the structure and spectroscopic properties of the PODIPY dye. Theoretically predicted coordination center geometries correspond to the ones found experimentally for phosphorus phthalocyanines, corrolazines and other known P(V) heterocyclic complexes. DFT and WFT methods are employed to study geometrical, energetical and resulting spectral characteristics of the structural isomers.

Synthesis and Spectral Characteristics of BODIPY Dyes with Two or Three Dipyrrin Domains.

Several boron-dipyrrin (BODIPY) based fluorophores with two and three dipyrrin cores were synthesized and investigated in solvents under the concentration variation. Comparative analysis of spectral and photophysical changes under increasing the number of the cores in the dye molecule was made. Mutual influence of dipyrrin cores was detected leading to the increasing of the compounds rigidity and, thus, the absence of fluorescent molecular rotor effects under the viscosity variation. Aggregation induced quenching, which was observed for many mono-domain BODIPY dyes is reduced in case of investigated poly-domain compounds.

BODIPY dyes in bio environment: Spectral characteristics and possibilities for practical application

Abstract Boron dipyrrin (BODIPY) dyes serve as perspective fluorescent sensors and probes in a vast range of biochemical and medical applications. Thus, mechanisms of interaction with biomolecules and accompanying spectral behavior of BODIPY are of major interest for fundamental science and practical applications. 8-aryl BODIPY derivatives were found to have high fluorescent respond upon the protein addition. Investigation of the interaction between the series of BODIPY complexes and Bovine Serum Albumin (BSA) using ultraviolet-visible (UV-vis) absorption, fluorescence spectroscopy under simulated physiological conditions (pH 7.4) and molecular docking methods was performed. The results of fluorescence spectroscopy indicated that the fluorescence of hydrophobic BODIPY dyes substantially increases in the presence of BSA. The prospected reason is binding of the dye to the BSA hydrophobic cavities in the subdomain IIA. Aromatic moiety size increase causes shifting of the interaction driving force from mostly non-specific to the π-stacking. Among all probes, the 8-phenyl substituted dye showed the highest sensitivity and the quantitative fluorescent response for BSA in aqueous solution. BODIPY with 8-phenyl substituent or analogs therefore could be used as protein surface polarity sensors, at the same time all of the investigated dyes with bulky aromatic groups could be used as hydrophobic molecule tags and markers for bioimaging tasks.

Fluorescent Properties of BODIPY Sensors Based on Photoinduced Electron Transfer.

Two boron-dipyrrin (BODIPY) based dyes with dimethylaminophenyl and carboxyphenyl substituents in 8-position of dipyrrin ligand have been synthesized and characterized. Photophysical and spectral properties of the obtained compounds have been investigated in water-ethanol mixture and water-cyclohexane system with variation of pH values. The equilibria constants of the compounds were identified by classical methods of acid-base titration. BODIPY bearing dimethylaminophenyl and carboxyphenyl subunits show deprotonation/protonation dependent fluorescence off/on-switching. The change of the emission could be mechanistically explained by a PET (photoinduced electron transfer) from the 8-substituent to the fluorophore. The present study demonstrates that BODIPY-based fluorescent sensors can be used to measure the pH in the range of 2-13 extending the scope of BODIPY dyes available as pH-indicators. Investigated compounds demonstrate weak dye-dye interaction allowing their cooperative usage as indicators.

Boron-Phenylpyrrin Dyes: Facile Synthesis, Structure, and pH-Sensitive Properties

Boron-phenylpyrrin dyes: In the presence of BF3⋅OEt2, 4-(diethylamino)salicylaldehyde reacts with substituted pyrroles to give boron-phenylpyrrin dyes, which contain a central boron-containing seven-membered ring. Upon protonation in acidic solution, the complexes, with a large Stokes shift, exhibit a color change and a unique red shift in both the electronic absorption and fluorescence emission spectra (see picture), thus rendering them new analogues of boron-dipyrrin dyes that can be used as pH sensors.

α‐/β‐Formylated Boron–Dipyrrin (BODIPY) Dyes: Regioselective Syntheses and Photophysical Properties

AbstractFormylation has been performed on pyrrole‐unsubstituted dipyrromethanes 1 and boron–dipyrrin (BODIPY) dyes 4 based on a Vilsmeier–Haack reaction. It is highly regioselective and complementary and occurs exclusively at the α‐ and β‐position, respectively, for pyrrole‐unsubstituted dipyrromethanes 1 and BODIPY dyes 4. This regioselective formylation enables the syntheses of a variety of α‐ and β‐substituted BODIPY dyes. The installation of formyl groups affects the electronic properties of the BODIPY chromophore, resulting in red‐ and blueshifts of the absorption and emission maxima, respectively, for the α‐ and β‐formylatedBODIPYs 3 and 5.

Solid-State Dye-Sensitized Solar Cells Using Red and Near-IR Absorbing Bodipy Sensitizers

Boron-dipyrrin dyes, through rational design, yield promising new materials. With strong electron-donor functionalities and anchoring groups for attachment to nanocrystalline TiO(2), these dyes proved useful as sensitizers in dye-sensitized solar cells. Their applicability in a solid-state electrolyte regime offers additional opportunities for practical applications.

Boron Dipyrrin Dyes Exhibiting “Push–Pull–Pull” Electronic Signatures

Manipulating the electronic pathway: A strategy has been devised for functionalizing boron dipyrrin dyes with one or two electroactive ferrocene units at the periphery. Oxidation of one or both ferrocene residues is fully reversible and gives rise to near-IR electrochromism. One-electron oxidation of the bis-derivative transforms the original “push–pull–push” system into a “push–pull–pull” signature.

Functionalization of Boron Dipyrrin (BODIPY) Dyes through Iridium and Rhodium Catalysis: A Complementary Approach to α‐ and β‐Substituted BODIPYs

Iridium-catalyzed direct borylation has been applied to meso-substituted dipyrromethane and boron dipyrrin (BODIPY) dyes. Borylation is highly regioselective and complementary: it occurs exclusively at the alpha position for meso-mesityldipyrromethane and at the beta positions for meso-mesityl BODIPY dye. This regioselective borylation enables a variety of alpha- and beta-substituted BODIPY dyes to be synthesized. Introduction of alpha,beta-enoate and alpha,beta,gamma,delta-dienoate functions into BODIPY dyes at the alpha or beta positions was achieved by rhodium-catalyzed Heck-type addition of the borylated compounds to acrylate and 2,4-pentadienoate esters. This functionalization has a significant effect on the electronic properties of BODIPY dyes, as seen in substantial redshift of the absorption and emission spectra. Comparative studies showed that the alpha- and beta-substituted series of BODIPY dyes show substantially different photophysical properties, and thus the importance of the position to be functionalized is highlighted.