Structure of holothurin A a biologically active triterpene-oligoglycoside from the sea cucumber holothuria leucospilota brandt

On the basis of chemical and physicochemical evidence, the structure of holothurin A, a biologically active major obligoglycoside o lanostane-type triterpene holothurigenol ($\text{2}$), has been elucidated to be $\text{8}$.     

On the construction of exact solutions of the stationary axially symmetric Einstein equations

Summary For the stationary axially symmetric vacuum, field, the Einstein equations reduce to a system for the logarithmic derivatives of the unknown function. An inverse scattering formula and a Bäcklund transformation are presented for the reduced system. As the simplest case, successive uses of the Bäcklund transformation give the Kasner type solutions and their generalization starting from the Minkowski metric.     

The structure of aureothin, a nitro compound obtained from Streptomyces thioluteus

The structure of aureothin, the third nitro compound obtained from nature, has been elucidated as I. Several reactions of aureothin and its derivatives are described.     

Nano‐imaging through tip‐enhanced Raman spectroscopy: Stepping beyond the classical limits

The spatial resolution in optical imaging is restricted by so‐called diffraction limit, which prevents it to be better than about half of the wavelength of the probing light. Tip‐enhanced Raman spectroscopy (TERS), which is based on the SPP‐induced plasmonic enhancement and confinement of light near a metallic nanostructure, can however, overcome this barrier and produce optical images far beyond the diffraction limit. Here in this article, the basic phenomenon involved in TERS is reviewed, and the high spatial resolution achieved in optical imaging through this technique is discussed. Further, it is shown that when TERS is combined with some other physical phenomena, the spatial resolution can be dramatically improved. Particularly, by including tip‐applied extremely localized pressure in TERS process, it has been demonstrated that a spatial resolution as high as 4 nm could be achieved.     

A steep one-step [HS-HS] to [LS-LS] spin transition in a 4,4'-bipyridine linked one-dimensional coordination polymer constructed from a pyrazolato bridged Fe(II) dimer

The variable temperature magnetic susceptibility, X-ray crystallography, and M?ssbauer and Raman spectra of a new dinuclear complex-based one-dimensional coordination polymer [[Fe(II)2(NCS)2(mu-bpypz)2](micro-4,4'-bpy)].MeOH demonstrated a steep one-step [HS-HS] to [LS-LS] spin transition.     

A new calix[5]arene-based container: selective extraction of higher fullerenes

[reaction: see text] A new double calix[5]arene successfully extracts higher fullerenes from fullerene mixtures. The syn isomer of the double calix[5]arene selectively captures higher fullerenes from fullerene mixtures. The elevation of the temperature more than 100 degrees C stimulates its conformational change to the anti isomer, bringing liberation of the captured higher fullerenes.