Bile Acids – Natural Building Blocks for Porous
Coordination Self-Assemblies
Subhasis Chattopadhyay1,2*, Radek Marek1,2, Ondřej Jurček1,2,3
1
Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-
62500 Brno, Czechia
2 CEITEC, Masaryk University, Kamenice 5, CZ-62500 Brno, Czechia
3 Department of Natural Drugs, Faculty of Pharmacy, Masaryk University, 61200 Brno,
Czechia
*subhasischattopadyay101@gmail.com
Self-assembly, metal coordination and chiral cavities are essential features of
natural organization. In the past three decades, various supramolecular
assemblies were synthesized via coordination-driven self-assembly using di- or
tritopic pyridyl ligands and square planar palladium(II).1
However, majority of
these assemblies are made of achiral ligands and do not contain chiral cavity.
Therefore, to mimic the natural chiral enzyme-like cavities, our group has
introduced the “next-generation” metallo-supramolecular assemblies, e.g.,
Pd3L6 (Fig. 1) using chiral bile acid-based (ursodeoxycholic acid, UDCA) ditopic
ligands.2
Figure 1. Bile acid-based metallo-macrocycles and coordination cages.
Further study showed that similar Pd3L6 can form hexagonal microparticles via
Hierarchical Self-Organization.3
To investigate the effect of ligand’s bend angle
on coordination self-assembly, chenodeoxycholic acid-based (CDCA, an epimer
of UDCA) ditopic ligand was used which results in a mixture of PdnL2n species
ranging from Pd2L4 to a large Pd6L12.4
Finally, UDCA-based tritopic ligand was
also synthesized and its self-assembly resulted in Pd6L8 (Fig. 1) and the first-ever
Pd12L16 supramolecular cage.5
1) Stang P. J. et. al. Chem.Rev. 2011, 111, 6810. 2) Jurček O. et al. Angew. Chem.
Int. Ed. 2015, 54, 15462. 3) Jurček O. et al. Cell Rep. Phys. Sci. 2021, 2, 100303.
4-5) Chattopadhyay S. and Jurček O. et al. manuscripts before submission.