Diphenylacetylene-linked peptide strands induce bidirectional β-sheet formation.

In the search for synthetic mimics of protein secondary structures relevant to the mediation of protein-protein interactions, we have synthesized a series of tetrasubstituted diphenylacetylenes that display β-sheet structures in two directions. Extensive X-ray crystallographic and NMR solution phase studies are consistent with these proteomimetics adopting sheet structures, displaying both hydrophobic and hydrophilic amino acid side chains.

Enaminone-based mimics of extended and hydrophilic α-helices.

Synthetic molecules capable of the mimicry of α-helices that are elongated and/or contain hydrophilic side chains have been largely elusive. However, the oligophenylenaminone structure can surmount both of these challenges (see scheme).

Aryl-linked imidazolidin-2-ones as non-peptidic β-strand mimetics.

We describe the design and synthesis of a non-peptidic β-strand mimetic composed of alternating aryl and imidazolidin-2-one rings that can be adapted to display diverse side-chains. Solid- and solution-phase data together with calculations suggest that the desired conformation for side-chain mimicry is readily accessible and well-populated.

Ferromagnetic Ni(II) discs.

A family of planar disc-like hexa-, octa- and decametallic Ni(II) complexes exhibit dominant ferromagnetic exchange. The deca- and octametallic clusters [Ni(II) (10)(tmp)(2)(N(3))(8)(acac)(6)(MeOH)(6)] (1, H(3)tmp=1,1,1-tris(hydroxymethyl)propane; acac=acetylacetonate) and [Ni(II) (8)(thme)(2)(O(2)CPh)(4)(Cl)(6)(MeCN)(6)(H(2)O)(2)] (2, H(3)thme=1,1,1-tris(hydroxymethyl)ethane) represent rare examples of Ni(II)-based single-molecule magnets, and [Ni(II) (10)] (1) possesses the largest barrier to magnetisation reversal of any Ni(II) single-molecule magnet to date.

Making "wheels" and "cubes" from triangles.

[Mn(IV)Mn(II)3] triangular units directed by the presence of tripodal alcohols self-assemble in the presence of azide and acetate ligands to form either a [Mn24] "wheel" or a [Mn32] "cube".

Synthesis, structure and magnetic properties of a trinuclear [Mn(III)Mn(II)2] single-molecule magnet.

Ferromagnetic exchange between the three Mn ions in the complex [Mn3(Hcht)2(bpy)4](ClO4)3 leads to a spin ground state of S = 7; single crystal studies reveal the temperature and sweep rate dependent hysteresis loops expected for a single-molecule magnet.