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Howard M Colquhoun

Publications and source records attributed to Howard M Colquhoun.

5 recordsLinked to original sources
PubMed2004

Principles of sequence-recognition in aromatic polyimides.

Pyrene-based molecular tweezers show sequence-specific binding to aromatic polyimides through sterically-controlled donor-acceptor pi-stacking and hydrogen bonding; (1)H NMR spectra of tweezer-complexes with polyimides having different sequence-restrictions show conclusively that the detection of long range sequence-information results from multiple tweezer-binding at adjacent imide residues.

Journal Article↗
PubMed2003

Extreme complementarity in a macrocycle-tweezer complex.

[reaction: see text] Interaction of a novel pyrene-based tweezer molecule with a macrocyclic ether-imide-sulfone results in formation of a strongly bound complex (K(a) = 24 000 M(-)(1)) in which binding results not only from pi-pi stacking interactions involving pyrene units as donors and macrocyclic naphthalene-tetracarboximide and biphenylenedisulfone groups as acceptors but also from N-H.O and C-H.O hydrogen bonds and from "reverse" pi-stacking of the electron-poor isophthaloyl residue of the tweezer with an electron-rich 3-aminophenoxy residue of the macrocyclic imide.

Journal Article↗
PubMed2002

Macrocyclic aromatic ether-imide-sulfones: versatile supramolecular receptors with extreme thermochemical and oxidative stability.

Macrocyclic receptors having extreme thermo-oxidative stability, and which bind a wide range of electron-donor substrates via pi-stacking donor-acceptor interactions, are accessible by cycloimidization of an amine-functionalized aryl ether-sulfone with pyromellitic dianhydride or 1,4,5,8-naphthalenetetracarboxylic dianhydride. The potential of these receptors in supramolecular chemistry is illustrated, for example, by the spontaneous self-assembly and crystallization of a five-component [3]pseudorotaxane from a solution of its constituents.

Journal Article↗