A Three-Component Assembly Promoted by Boronic Acids Delivers a Modular Fluorophore Platform (BASHY Dyes)

Graphical Abstract

“The photophysical properties, especially the brightness of the dyes, surpassed our most optimistic expectations.” Read more about the story behind the cover in the Cover Profile and about the research itself on page 1631 ff. (DOI: 10.1002/chem.201503943).

Abstract

Invited for the cover of this issue are Uwe Pischel, Pedro Gois and co-workers at the Universities of Huelva and Lisbon. The image depicts a puzzle, which symbolizes the multicomponent reaction used to prepare a series of boronic acid salicylidenehydrazone (BASHY) dyes that are applied in cell staining. Read the full text of the article at 10.1002/chem.201503943.

How did the collaboration on this project start?

As in many cases, it started with a meeting of the two corresponding authors at a conference; in this particular case at the National Meeting of the Portuguese Society of Chemistry in Aveiro in the summer of 2013. The first discussions were driven by curiosity for each other's research and relatively fast it crystallized that there was a mutual interest in fluorescent probes with potential applications in chemical biology. From there, it was short step to identifying the useful complementarities of the involved research groups. Geographical closeness, the common concerns of researchers that pursue their careers in the south of Europe, and personal sympathies helped to set up the collaboration with a lot of human quality (despite the support of rival football teams).

What aspects of this project do you find most exciting?

On the one hand, the multicomponent synthesis of BASHY dyes is so straightforward that even rather inexperienced students will not fail. On the other hand, their molecular and functional diversity is tremendous. We foresee that these dyes can be tailor-made for the most varied applications with an emphasis on bioimaging. The photophysical properties, especially the brightness of the dyes, surpassed our most optimistic expectations. It was real fun to work with these molecules and everyone in the laboratory likes them for their notable light emission.

Does the research open other avenues that you would like to investigate?

As pointed out in the answer for the preceding question, BASHY dyes can be designed for a broad range of bioimaging applications. We are now particularly interested in using them as polarity-responsive dyes for biological problems. The insertion of one of the collaborating groups in the Research Institute for Medicines and Pharmaceutical Sciences (iMed) at the University of Lisbon will hopefully provide the driving force needed to make the next steps.

What was the inspiration for this cover design?

The cover design shows the different facets of our project: multicomponent reactions, assembly of fluorescent dyes, and their first applications for cell staining. The puzzle illustrates the fact that only the “right pieces” come together, as the final BASHY dyes are obtained in virtually quantitative yield and high purity. Puzzles are a favorite toy of many children, which underpins the relative ease of the procedure.