Binding sites on the outside of metallo-supramolecular architectures; engineering coordination polymers from discrete architectures.

Aggregation of metallo-supramolecular architectures through additional coordination is explored by introducing metal-binding units onto the outside of the supramolecular architectures. This is achieved within the framework of our imine-based approach to supramolecular architecture, by replacing the pyridylimine units with pyrazylketimine units. An advantage of the design is that it retains the ease-of-synthesis which characterises our imine-based approach.

Conformational investigation of alpha,beta-dehydropeptides. XIII. Conformational properties of N-acetyl-alpha,beta-dehydrovaline N',N'-dimethylamide.

The crystal structure of Ac-DeltaVal-NMe(2) (DeltaVal = alpha,beta-dehydrovaline) was determined by X-ray crystallography. The found angles phi = -60 degrees and psi = 125 degrees correspond exactly to the respective values of the (i + 1)th residue in idealised beta-turn II/VIa. Ab initio/DFT studies revealed that the molecule adopts the angle psi restricted only to about |130 degrees | and very readily attains the angle phi = about -50 degrees.