Supramolecular chemistry is actively exploring systems undergoing self-organization, i.e. systems
capable of spontaneously generating well-defined functional supramolecular architectures by selfassembly
from their components, on the basis of the molecular information stored in the covalent
framework of the components and read out at the supramolecular level through specific interactional
algorithms, thus behaving as programmed chemical systems.
Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the
interactions connecting the molecular components of a supramolecular entity and the resulting ability
of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular
entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution
by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on
both the molecular and supramolecular levels.
CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the
generation of a target entity, whereas CDC takes advantage of dynamic constitutional diversity to allow variation and
selection so as to achieve adaptation.
In the process of reaching higher levels of complexity, CDC gives access to the generation of networks of dynamically
interconverting constituents connected either structurally (molecular and supramolecular arrays) or reactionnally (set of
connected reactions) or both. They define a class of constitutional dynamic networks (CDNs), presenting agonistic and
antagonistic relationships between their constituents, that may couple to thermodynamic or kinetic processes and
respond to perturbations by physical stimuli or to chemical effectors.
Applications of these approaches to biological systems and to drug discovery will be described.