Formation and structural, energetic and dynamic properties of cyclodextrin host tubes and included guest molecules

Probing topology of supramolecular complexes between cyclodextrins and alkali metals by ion mobility-mass spectrometry

“…In tubular arrangements of CDs, they can interact among themselves according to three possible orientations: Head-to-Tail (HT), Head-to-Head (HH) or Tail-to-Tail, (TT). (Staelens et al, 2015) Such organization is the result of the formation of several intermolecular hydrogen bonds constituting the main driving force for holding and stabilizing two or more units together. (Nascimento et al, 2005) As example, we have investigated the ion mobility traces of the singly charged ion at m/z 1967.6199 ascribed to [(-CD)2+Na] + and deducted corresponding CCS values (Fig.…”

“…Furthermore, previous studies have demonstrated that favourable elongation of -CD based tubular arrangements corresponds to a decrease of the potential energy value of the tubes per CD unit as a function of the number of CDs. (Staelens et al, 2015) The important flexibility of -CD leads to a more compressed staked assembly during the trimer formation compared to -and -CD where a quite more incremental addition of monomer of semi-rigid structure seems to take place. Such phenomenon can explain why the CCS difference between di-(HH) and trimer (HTHT) is by far lower than from monoto dimer.…”