Grynszpan Lab


alpha-Aminoisobutyric acid leads a fluorescent syn-bimane LASER probe across the blood-brain barrier.
By, I. Lapidot, D. Baranes, A. Pinhasov, G. Gellerman, A. Albeck, F. Grynszpan, and Sh.E. Shatzmiller. Medicinal Chemistry, 12(1), 48-53, (2016). DOI: 10.2174/1573406411666150518105010

Penetration of the blood brain barrier (BBB) by appropriate fluorescent probes remains a challenge in optical imaging and diagnostics. We designed, synthesized and observed the in vivo BBB penetration of a LASER syn-bimane probe. Results demonstrate that the Aib transporter unit in our probe may lead a fluorescent bimanyl moiety across the BBB.


syn-Bimane as a Chelating O-Donor Ligand for Palladium(II).
By P.J. Das, Y. Diskin-Posner, M. Firer, M. Montag, and F. Grynszpan. Dalton Trans., 45, 17123-17131 (2016). DOI: 10.1039/C6DT02141G. Highlighted as the cover of the Journal.

A cationic Pd(II) complex containing syn-(Me,Me)bimane as a ligand was prepared and fully characterized. This complex represents the first well-defined case of a bimane scaffold coordinated to a metal center. The strongly-fluorescent syn-bimane chelates the Pd(II) center via its carbonyl oxygen atoms, affording a non-fluorescent complex. The crystal structure of this complex shows that the coordinated bimane departs from planarity, with its bicyclic framework bent about the N–N bond. Spectroscopic evidence demonstrates that bimane coordination is reversible in solution.

Dihalogen and solvent free preparation of syn-bimane.
By I. Neogi, P. J. Das and F. Grynszpan. Synlett. 29 (08), 1043-1046 (2018). DOI: 10.1055/s-0036-1591964.

Fluorescent bimanes are low molecular weight and low toxicity molecules with applications ranging from biology to LASER dyes. The widespread use of these molecular probes has presumably been stalled by the hazards involved in their current synthetic preparation which involve handling of dangerous halogens like chlorine (gas) and bromine (liq.). The accessibility achieved by the simple and safe dihalogen and solvent-free methodologies described here open the floodgates to additional future practical applications of bimanes.

Quenching of syn-Bimane Fluorescence by Na+ Complexation.
By A. Roy, P.J. Das, Y. Diskin-Posner, M. Firer, F. Grynszpan, and M. Montag. New J. Chem. 42, 15541-15545 (2018). DOI: 10.1039/C8NJ01945B

The fluorescent dye syn-(Me,Me)bimane interacts with the biorelevant Na+ ion to form labile complexes, three of which were crystallographically characterized, exhibiting new modes of bimane coordination. In water, as well as in organic solvents, Na+ complexation induces the quenching of bimane fluorescence.

syn-(Me,Me)Bimane as a Structural Building Block in Metal Coordination Architectures.

By Y. Diskin-Posner, S. Amer, A. Roy, P. J. Das, F. Grynszpan, and M. Montag. Crystal Growth & Design (2019).

Li(I) and Na(I) complexes of the fluorescent dye syn-(Me,Me)bimane were isolated and crystallographically characterized, revealing the bimane as a principal component in diverse coordination topologies, including discrete and polymeric structures. The bimane exhibits multiple functions in these frameworks, acting as a variable-denticity O-donor ligand, π-stacking unit, and hydrogen bond acceptor. These features highlight a new role for syn-bimanes, not as fluorophores, but as versatile building blocks in metal coordination architectures.