Medicinal carbon tablets for treatment of acetaminophen intoxication: adsorption characteristics of medicinal carbon powder and its tablets

Adsorption characteristics of medicinal carbon powder (JP 14) for acetaminophen were examined at 37 degrees C using conventional incubation in an attempt to obtain an effective oral dosage form. Hydroxypropyl cellulose (HPC) and maltitol (MT), being able to act as a binding agent, were tested as additives. Tablets of medicinal carbon were produced by the wet granulation method. The rate and extent of adsorption of the medicinal carbon powder were roughly similar in water, JP 14 1st fluid (pH 1.2) and JP 14 2nd fluid (pH 6.8). The relationship between concentrations of free and adsorbed acetaminophen indicated that the adsorption followed the Langmuir mode. The maximal adsorption of acetaminophen in water was 0.219 g per gram medicinal carbon powder, little influenced by the addition of MT, but slightly reduced by the addition of HPC. The tablet prepared using MT as a binding agent displayed a favorable hardness and adequate disintegration time. The tablet showed good adsorption potential for acetaminophen, though the adsorption rate and extent of the tablet were reduced to some extent as compared with powder.     

Photophysical properties and excitation polarization of fac/mer-ruthenium complexes with 5'-amino-2,2'-bipyridine-5-carboxylic acid derivatives

Novel ruthenium(II) complexes, fac/mer-[Ru(MeCO-5Bpy-R)3]2+ (H-5Bpy-OH = 5'-amino-2,2'-bipyridine-5-carboxylic acid; R = -NHtBu, -NH(cHex), -N(cHex)2), have been synthesized. The fac and mer isomers have been successfully separated using HPLC techniques, and their photophysical/electrochemical properties have been investigated. In the absorption and emission spectra of fac/mer-[Ru(MeCO-5Bpy-R)3]2+ with secondary amines (R = -N(cHex)2) in acetonitrile at room temperature, the maximum wavelengths based on the MLCT are longer than those for the amide derivatives with primary amines (R = -NHtBu, -NH(cHex)). A small solvent effect on the photophysical properties between fac- and mer-[Ru(MeCO-5Bpy-NHtBu)3]2+ has been observed. The excitation polarization spectra, giving P values reflecting the relation between the absorption and the emission oscillators, for the fac- and mer-ruthenium(II) complexes (C3 and C1 symmetry, respectively) have been measured for the first time. Almost no difference in the excitation polarization spectra between the fac and mer complexes is found, and these spectra are similar to that for [Ru(bpy)3]2+ with D3 symmetry. This finding suggests that the orientations of the absorption and emission oscillators, in the case of the ruthenium(II) tris(2,2'-bipyridine) derivatives, would not be affected by the symmetries of the complexes and that the P values for any derivatives would be similar to that for [Ru(bpy)3]2+.     

Direct synthesis of fused indoles by gold-catalyzed cascade cyclization of diynes

A direct, concise, and atom-economical synthetic method for the generation of fused indoles, using a gold-catalyzed cascade cyclization of diynes, has been developed. The reaction gave various fused indoles, such as aryl-annulated[a]carbazoles, dihydrobenzo[g]indoles, and azepino- or oxepinoindole derivatives in good to excellent yields, through an intramolecular cascade 5-endo-dig hydroamination followed by a 6- or 7-endo-dig cycloisomerization, without producing theoretical byproduct. Three of the resulting indoles exhibited potent antifungal activities against T. mentagrophytes and T. rubrum, demonstrating the practical application of the described cascade reaction for drug discovery.     

An example of the Weierstrass semigroup of a pointed curve on K3 surfaces

Let X be a K3 surface with Picard number one which is given by a double cover π:X→?². Let C be a smooth curve on X with π ^?1 π(C)=C which is not the ramification divisor of π, and let P be a ramification point of π| _C :C→π(C). In this paper, in the case where the intersection multiplicity at π(P) of the curve π(C) and the tangent line at π(P) on π(C) is equal to deg(π(C)) or deg(π(C))?1, we investigate the Weierstrass semigroup of the pointed curve (C,P).     

Thermal properties of AlN–Ce:YAG composite ceramic phosphor for laser lighting

Optical Review - The AlN–Ce:YAG composite ceramic is an effective phosphor for high-power laser illumination. The thermal properties of an AlN–Ce:YAG composite phosphor were studied to...     

Aerobic Dehydrogenation of N-Heterocycles with Grubbs Catalyst: Its Application to Assisted-Tandem Catalysis to Construct N-Containing Fused Heteroarenes

An aerobic dehydrogenation of nitrogen-containing heterocycles catalyzed by Grubbs catalyst is developed. The reaction is applicable to various nitrogen-containing heterocycles. The exceptionally high functional group compatibility of this method was confirmed by the oxidation of an unprotected dihydroindolactam V to indolactam V. Furthermore, by taking advantage of the oxygen-mediated structural change of the Grubbs catalyst, we integrated ring-closing metathesis and subsequent aerobic dehydrogenation to develop the novel assisted-tandem catalysis using molecular oxygen as a chemical trigger. The utility of the assisted-tandem catalysis was demonstrated by the concise synthesis of N-containing fused heteroarenes including a natural antibiotic, pyocyanine.     

Welding dynamics in an atomistic model of an amorphous polymer blend with polymer–polymer interface

We consider an atomistic model of thermal welding at the polymer-polymer interface of a polyetherimide/polycarbonate blend, motivated by applications to 3D manufacturing in space. We follow diffusion of semiflexible chains at the interface and analyze strengthening of the samples as a function of the welding time t_w by simulating the strain–stress and shear viscosity curves. The time scales for initial wetting, and for fast and slow diffusion, are revealed. It is shown that each component of the polymer blend has its own characteristic time of slow diffusion at the interface. Analysis of strain–stress demonstrates saturation of the Young's modulus at t_w = 240 ns, while the tensile strength continues to increase. The shear viscosity is found to have a very weak dependence on the welding time for t_w > 60 ns. It is shown that both strain–stress and shear viscosity curves agree with experimental data.     

Formal total synthesis of (+)-lysergic acid via zinc(II)-mediated regioselective ring-opening reduction of 2-alkynyl-3-indolyloxirane

Asymmetric formal synthesis of (+)-lysergic acid was achieved with a reductive ring-opening reaction of chiral 2-alkynyl-3-indolyloxirane with NaBH(3)CN as the key step. With Zn(OTf)(2) as an additive, the ring-opening reaction proceeded regioselectively at the 3-position to give the corresponding propargyl alcohol, which was a precursor of the allenic amide for palladium-catalyzed domino cyclization to construct the ergot alkaloid core structure.