Production of Quaternary α-Aminonitriles by Means of Indium-Catalyzed Three-Component Reaction of Alkynes, Amines, and Trimethylsilyl Cyanide.

A novel synthesis of α-aminonitriles is described via an indium-catalyzed three-component coupling reaction of alkynes, amines, and trimethylsilyl cyanide (Me3SiCN). Hydroamination of alkynes with a subsequent nucleophilic addition of Me3SiCN resulted in a novel approach to quaternary α-aminonitrile derivatives.

Ultrafast slow-light tuning beyond the carrier lifetime using photonic crystal waveguides.

We demonstrate ultrafast delay tuning of a slow-light pulse with a response time <10 ps. This is achieved using two types of slow light: dispersion-compensated slow light for the signal pulse, and low-dispersion slow light to enhance nonlinear effects of the control pulse. These two types of slow light are generated simultaneously in Si lattice-shifted photonic crystal waveguides, arising from flat and straight photonic bands, respectively.

Fabrication and characterization of chalcogenide glass photonic crystal waveguides.

We report on the fabrication of chalcogenide glass (Ag-As(2)Se(3)) photonic crystal waveguides and the first detailed characterization of the linear and nonlinear optical properties. The waveguides, fabricated by e-beam lithography and ICP etching exhibit typical transmission spectra of photonic crystal waveguides, and exhibit high optical nonlinearity. Nonlinear phase shift of 1.

Dispersion-controlled slow light in photonic crystal waveguides.

Slow light with a markedly low group velocity is a promising solution for optical buffering and advanced time-domain optical signal processing. It is also anticipated to enhance linear and nonlinear effects and so miniaturize functional photonic devices because slow light compresses optical energy in space. Photonic crystal waveguide devices generate on-chip slow light at room temperature with a wide bandwidth and low dispersion suitable for short pulse transmission.

Slow light with low dispersion and nonlinear enhancement in a lattice-shifted photonic crystal waveguide.

We discovered that a silicon-on-insulator photonic crystal waveguide whose lattice is shifted along the waveguide generates wideband, low-dispersion, slow light with excellent reproducibility. We observed delayed transmission of picosecond optical pulses, as well as two-photon absorption and self-phase modulation enhanced by a high internal light intensity in the slow-light regime.

Simple and rapid high-performance liquid chromatography analysis of propentofylline and its main metabolites in serum using a direct injection technique.

A rapid, simple and reliable high-performance liquid chromatography (HPLC) column-switching method with UV detection (270 nm) for the simultaneous determination of propentofylline and its metabolites in human and rat sera was developed. The method involves direct injection of serum onto an HPLC column, which contains a shielded hydrophobic stationary phase for the separation of analytes from proteins in serum, and then loading the analytes onto a short octadecylsilylated silica gel (ODS) column using a switching valve. Propentofylline and its three metabolites in serum were separated from the serum components within 30 min after the injection.

Predictive performance of equations to estimate creatinine clearance from serum creatinine in Japanese patients with congestive heart failure.

Seven methods using patient's age, weight, gender, and serum creatinine concentration were evaluated for mathematical and clinical predictive performance in estimating the creatinine clearance of Japanese patients. We compared the measured and estimated creatinine clearance in 179 hospitalized heart failure patients. The Gates equation was the most biased (mean prediction error, 17.

High-performance liquid chromatography with peroxyoxalate chemiluminescence determination of propentofylline concentrations in rat brain microdialysate.

A high-performance liquid chromatographic determination of a neuronal cell protective compound, propentofylline [3-methyl-1-(5-oxohexyl)-7-propyl-7H-purine-2(3H),6(1H)-dione] was performed combining a microdialysis technique with peroxyoxalate chemiluminescence (PO-CL) detection. The microdialysate was subjected to a fluorescent derivatization of propentofylline with 4-(N,N-dimethylaminosulfonyl)-7-hydrazino-2,1,3-benzoxadiazole (DBD-H) without further cleanup, because the membrane used in the microdialysis excluded high-molecular-mass proteins. The proposed method showed a good linearity in the determination range of 0.

Use of 3-(1,8-naphthalimido)propyl-modified silyl silica gel as a stationary phase for the high-performance liquid chromatographic separation of purine derivatives.

The use of a packing material, 3-(1,8-naphthalimido)propyl-modified silyl silica gel (NAIP), as a stationary phase for high-performance liquid chromatography, has been studied. NAIP behaved like a reversed-phase stationary phase with some pi-pi interaction. Purine derivatives, i.

High-performance liquid chromatography with fluorescence detection of ebiratide using 4-(N,N-dimethylamino-sulphonyl)-7-fluoro-2,1,3-benzoxadiazole as a fluorogenic reagent.

A sensitive high-performance liquid chromatography (HPLC) method with fluorescence detection has been developed and applied to the determination of ACTH4-9 analogue (ebiratide). 4-(N,N-Dimethylamino-sulphonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) was used as a fluorogenic labelling reagent. Ebiratide in 0.