Spontaneous helical folding of bis(Ni-salphen) complexes in solution and in the solid state: spectroscopic tracking of the unfolding process induced by Na(+) ions.

Four kinds of bis(Ni-salphen) complexes containing a 2-methylenepropane-1,3-diyl linker were synthesised and characterised. Crystal structural analysis revealed that one of the complexes folded into a helical structure, in which two Ni atoms were at a distance of 3.2 Å from each other.

Facile preparation of a fully π-conjugated metallopolymer composed of fused salphen complexes.

Novel π-conjugated compounds composed of fused salphen groups as a repeating unit, embedded with four or an indefinite number of zinc nuclei have been synthesized. The solid-state absorption spectra, IR spectra, and powder XRD patterns of these compounds are investigated and compared with those of analogous oligomers. The presumptive polymer contains at least five units of the salphen complex and its assembly is highly ordered in the solid state.

Comparison of the spectroscopic properties of π-conjugated, fused salphen triads embedded with Zn-homo-, Ni-homo-, and Ni/Zn-heteronuclei.

Stepwise condensation reactions of 2,6-dihydroxynaphthalene-1,5-dicarbaldehyde and a phenylenediamine with concomitant binding of metal ions afforded a trinuclear complex of a fully π-conjugated, fused salphen ligand. By changing the synthetic pathway, we obtained a series of homo- and heteronuclear complexes containing selected combinations of nickel(II) and zinc(II) ions. Comparison of the trinuclear complexes' spectroscopic features with those of analogous dinuclear complexes revealed that the absorption spectrum of each trinuclear complex is composed of a salphen-centered absorption at 400 nm and a naphthalene-centered absorption around 500-600 nm, suggesting that the π-conjugated system is divided into several compartments, each of which independently undergoes electronic excitation.

Twin salphen: asymmetric heterodinuclear complexes {M(a)M(b)L | M(a), M(b) = Ni, Cu, Zn} of a symmetrically fused salphen ligand.

Heterodinuclear complexes of a fully pi-conjugated salphen ligand were efficiently synthesized with arbitrary combinations of Ni(II), Cu(II), and Zn(II). The UV-vis spectra of the heterodinuclear complexes were approximately represented by a simple average of the spectra of the corresponding homodinuclear complexes. Systematic analysis of the spectra highlighted weak intracomplex interactions through the pi-conjugated system of the ligand.

Stimulus-induced behavior in F1 hybrids of seizure-sensitive and seizure-resistant gerbils.

We previously established two strains of Mongolian gerbil: a seizure-sensitive strain, established by selective inbreeding for motor seizures elicited by a stimulus called the S method and a seizure-resistant strain that does not exhibit inducible seizures. The behavior of the seizure-sensitive strain is characterized by a progressive increase in responsiveness to weekly application of the S method, from repetitive backward ear movements appearing after postnatal day 40, to a full-blown seizure, while the seizure-resistant strain is apparently unaffected by the stimulation. The difference between these two strains is presumably genetic.

Analysis of variance study of the rat cortical layer 4 barrel and layer 5b neurones.

Unique formation of rodent cortical barrels by layer 4 neurones attracts study of the sensory function of cortical input stage neurones (layer 4) compared with that of output stage neurones (layer 5). We have recorded extracellular responses from rat somatosensory cortical neurones to deflections of contralateral vibrissae. Thirty-two layer 4 barrel neurones and 29 layer 5b neurones were studied.