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A series of tetradentate amine(bisphenolate) ligands have been synthesized and complexed to Ti(IV), Zr(IV), and Hf(IV) centers. Two distinct ligand sets have been synthesized both exhibiting ONNO coordination. The steric bulk of the ligands was varied to assess the impact of sterics on the catalytic performance in the ring-opening-polymerization (ROP) of cyclic esters. In all cases the metal centers are pseudo octahedral in geometry. Several group 4 amine(bisphenolate) complexes have been characterized by single-crystal X-ray diffraction. The complexes were tested for the ROP of -caprolactone and L/rac-lactide, with significant activity seen for complexes of all group 4 metals. For Ti(IV), complexes of sterically demanding ligands were more effective initiators, whereas sterically less demanding ligands were more successful for Zr(IV) complexes. Copolymers of poly(-caprolactone) and poly-l-lactide were produced utilizing the Zr(IV) initiators. The polymerization of rac-lactide was also studied allowing stereoselectivity of a range of metal−ligand combinations to be assessed. Isotactic polymer was produced with both Zr(IV) and Hf(IV) centers whereas Ti(IV) produced an atactic polymer.

To examine the potential role of fibroblast growth factor (FGF) signalling during cell differentiation, we used conditionally immortalised podocyte cells isolated from kidneys of Fgf2 mutant and wild-type mice. Wild-type mouse podocyte cells upregulate FGF2 expression when differentiating in culture, as do maturing podocytes in vivo. Differentiating wild-type mouse podocyte cells undergo an epithelial to mesenchymal-like transition, reorganise their actin cytoskeleton and extend actin-based cellular processes; all of these activities are similar to the activity of podocytes in vivo. Molecular analysis of Fgf2 mutant mouse podocyte cells reveals a general disruption of FGF signalling as expression of Fgf7 and Fgf10 are also downregulated. These FGF mutant mouse podocyte cells in culture fail to activate mesenchymal markers and their post-mitotic differentiation is blocked. Furthermore, mutant mouse podocyte cells in culture fail to reorganise their actin cytoskeleton and form actin-based cellular processes. These studies show that FGF signalling is required by cultured podocytes to undergo the epithelial to mesenchymal-like changes necessary for terminal differentiation. Together with other studies, these results point to a general role for FGF signalling in regulating cell differentiation and formation of actin-based cellular processes during morphogenesis.

The reaction of a toluene solution of PhNC(Ph)NHPh (N,N′-diphenylbenzamidine) with n-butyllithium gave the toluene-solvated amidinolithium compound {Li[PhNC(Ph)NPh]}n1. Similarly the same reaction performed in the presence of the Lewis-base donors (Me2N)3PO (hmpa), Me2N(CH2)2NMe2 (tmen) or [Me2N(CH2)2]2NMe (pmdien) yielded the amidinolithium complexes {Li[PhNC(Ph)NPh·hmpa]}22, {Li[PhNC(Ph)NPh]·tmen} 3 and {Li[PhNC(Ph)NPh]·pmdien} 4 respectively. In addition the reaction of a toluene solution of the related amidine PhNC(Me)NHPh (N,N′-diphenylacetamidine) with LiBun in the presence of hmpa afforded {Li[PhNC(Me)NPh]·hmpa}25. The solid-state structures of 2–5, which have been resolved by single-crystal X-ray diffraction methods, show both similarities and differences. The complexes 3 and 4, which contain the di- and tri-dentate ligands tmen and pmdien respectively, are monomeric, whilst use of the unidentate Lewis base hmpa results in dimers 2 and 5. However, the way in which dimerisation is achieved differs. The co-ordination geometry about the lithium cation is clearly influenced by the choice of donor and as such shows how a change in the denticity of the donor ligand utilised can have a significant effect on the solid-state structure of the system.

The structures of the adduct nido-C2B10H12·HNP(NMe2)3 and the borenium salt [(Me2N)3PNHBNP(NMe2)3]2O2+(C2B9H12–)2, both obtained from 1,2-C2B10H12 and HNP(NMe2)3, were determined by X-ray crystallography; the adduct represents the first structurally determined carborane of its type, a possible intermediate in the well known conversion of closo-1,2-C2B10H12 into the nido-7,8-C2B9H12– anion by bases.

Tetralithiation of tert-butylcalix[4]arene in the presence of hmpa (hexamethylphosphoramide) results in the isolation of either a monomeric complex in which LiOH is incorporated into an Li5O5 core based on an isolated square pyramid of Li atoms, or a dimeric LiOH-free species containing an Li8O8 core in which the same structural motif is maintained by edge-sharing of two square pyramids of Li atoms.

Iminophosphorane anions are shown to be novel and very powerful Lewis-base donors to s-block metals by the isolation and structural characterisation of N-lithio-iminophosphorane·lithium bromide adducts.