1443005-75-1Relevant academic research and scientific papers
A pH-sensitive peptide-containing lasso molecular switch
Clavel, Caroline,Fournel-Marotte, Karine,Coutrot, Frdric
, p. 11553 - 11575 (2013)
The synthesis of a peptide-containing lasso molecular switch by a self-entanglement strategy is described. The interlocked [1] rotaxane molecular machine consists of a benzometaphenylene[25]crown-8 (BMP25C8) macrocycle surrounding a molecular axle. This molecular axle contains a tripeptidic sequence and two molecular stations: a N-benzyltriazolium and a pH-sensitive anilinium station. The tripeptide is located between the macrocycle and the triazolium station, so that its conformation can be tailored depending on the shuttling of the macrocycle from one station to the other. At acidic pH, the macrocycle resides around the anilinium moiety, whereas it shuttles around the triazolium station after deprotonation. This molecular machinery thus forces the lasso to adopt a tightened or a loosened conformation.
A pH-sensitive lasso-based rotaxane molecular switch
Clavel, Caroline,Romuald, Camille,Brabet, Emile,Coutrot, Frédéric
, p. 2982 - 2989 (2013)
The synthesis of a pH-sensitive two-station [1]rotaxane molecular switch by self-entanglement of a non-interlocked hermaphrodite molecule, containing an anilinium and triazole moieties, is reported. The anilinium was chosen as the best template for the macrocycle benzometaphenylene[25]crown-8 (BMP25C8) and allowed the self-entanglement of the molecule. The equilibrium between the hermaphrodite molecule and the pseudo[1]rotaxane was studied by 1H NMR spectroscopy: the best conditions of self-entanglement were found in the less polar solvent CD2Cl2 and at high dilution. The triazole moiety was then benzylated to afford a benzyltriazolium moiety, which then played a dual role. On one hand, it acts as a bulky gate to trap the BMP25C8, thus to avoid any self-disentanglement of the molecular architecture. On another hand, it acts as a second molecular station for the macrocycle. At acidic pH, the BMP25C8 resides around the best anilinium molecular station, displaying the lasso [1]rotaxane in a loosened conformation. The deprotonation of the anilinium molecular station triggers the shuttling of the BMP25C8 around the triazolium moiety, therefore tightening the lasso. Molecular lasso: The synthesis of a [1]rotaxane molecular switch has been realized by self-entanglement of a hermaphroditic molecule. This is composed of an anilinium template (see figure, green ball) on a molecular tail, which is linked to a BMP25C8 macrocyclic head (red wheel). The trapping of the structure could be achieved by using triazolium (pink ball) as a molecular station and gate at the same time. A variation in pH triggers the tightening and loosening of the lasso. Copyright
