Separation of gallic acid from Cornus officinalis Sieb. et Zucc by high-speed counter-current chromatography

Gallic acid was separated from a n-butanol extract of the fruit of Cornus officinalis Sieb. et Zucc by high-speed countercurrent chromatography in two steps using two solvent systems composed of ethyl-acetate-ethanol n-butanol-water (5:1.8:6, v/v/v) and ethyl acetate-ethanol-water (5:0.5:6, v/v/v) successively. From 1 g of n-butanol extract the method produced 60 mg of gallic acid at a purity of 97%.     

Lactone and cyclic ether analogues of platelet-activating factor. Synthesis and biological activities

Six-membered lactone and tetrahydropyran analogues of platelet-activating factor (PAF), 4-11, and related antagonistic derivatives 41-46 were synthesized. None of the delta-lactones 4-7 showed PAF-like activities, while the corresponding cyclic ethers 8, 9 and 11 were slightly active. Some of the cyclic antagonists showed more potent inhibitory activities than the open chain antagonist CV-3988 against platelet aggregation (rabbit platelet-rich plasma, IC50) and hypotension (rat, ID50) induced by C16-PAF: e.g. dl-3-[6-[O-(trans-3-heptadecylcarbamoyloxytetrahydropyran-2- yl)methyl]phosphonoxy]hexylthiazolium (inner salt) (41d) (IC50 5.5 x 10(-7) M, ID50 0.046 mg/kg, i.v.); dl-3-[5-[O-(cis-3-heptadecylcarbamoylthiotetrahydropyran-2- yl)methyl]phosphonoxy]pentylthiazolium (inner salt) (43c) (IC50 5.7 x 10(-7) M, ID50 0.076 mg/kg, i.v.).     

Supramolecular porphyrin-fullerene via 'two-point' binding strategy: axial-coordination and cation-crown ether complexation

A highly stable porphyrin-fullerene conjugate with defined distance and orientation, was formed using a newly developed 'two-point' binding strategy involving axial-coordination and cation-crown ether complexation; photochemical studies performed in benzonitrile revealed efficient charge separation and slow charge-recombination in the supramolecular complex.     

PI Mtoyoura: a new PI M subtype found by separator and hybrid isoelectric focusing

In the course of a population study of alpha 1-antitrypsin polymorphism by separator isoelectric focusing, a variant phenotype having a somewhat narrower spacing than PI M1M3 was observed in a Japanese blood donor. Family studies by hybrid isoelectric focusing in a carrier ampholyte-supplemented immobilized pH gradient from 4.35-4.65 revealed that the products of the responsible gene, PI*Mtoyoura, were extremely close but slightly cathodal to those of PI*M1. The difference in isoelectric point between them corresponded to the resolving limit of isoelectric focusing. For this reason, although the propositus' father was deduced to have the genotype PI*M1/PI*Mtoyoura, the products of these two genes failed to form a double band pattern. Thus, the gene frequency for PI*Mtoyoura was unknown. These findings, however, indicate that a further microheterogeneity in the PI M subtype exists at least in the Japanese.     

CHOICE OF COATINGS FOR THE OPTICAL ELEMENTS IN THE IRRADIATION SYSTEM OF VACUUM-ULTRAVIOLET RADIATION ABOVE 50 nm

The spectral throughput of a vacuum-ultraviolet irradiation system at the SOR-RING facility was examined with various combinations of aluminum-and gold-coated optical elements in a 2.2-m modified Wadsworth monochromator. We found that the optimum was a combination of an aluminum-coated collimating mirror, concave grating, and plane deflecting mirror, and a combination of a gold-coated collimating mirror, concave grating and an aluminum-coated plane deflecting mirror in the wavelength regions 190-110 nm and 110-50 nm, respectively.     

The termination reaction in free radical copolymerization. I. Methyl methacrylate and butyl- or dodecyl methacrylate

Using a spatially intermittent reactor, the absolute rate constant for the termination reaction in free radical copolymerization has been measured for the monomer pair methyl methacrylate (MMA)–butyl methacrylate (BMA). For the pair MMA–dodecyl methacrylate (DMA) the relative rate constant for termination has been measured. In both cases the termination rate constant was a monotonically changing function of the monomer feed composition. This function can be well approximated by a simple calculation of the enchained monomer units' contributions to the average segmental friction coefficient of the copolymer chain. An attempt to apply a previously derived theoretical treatment based on penultimate unit effects produced physically unrealistic results.     

Phlomisflavosides A and B, new flavonol bisglycosides from Phlomis spinidens

From the aerial parts of Phlomis spinidens, two new flavonol bisglycosides, phlomisflavosides A (1) and B (2), were isolated together with the known compounds, astragalin, isoquercitrin, lamiridoside, phlomoside A, shanzhiside methyl ester, 8-O-acetylshanzhiside methyl ester, phlorigidoside C, rodioloside (=salidroside), forsythoside B, citroside A and lariciresinol-4'-O-beta-D-glucoside. The structures of the new compounds were elucidated based on spectral and chemical evidence.