New steroid‐group‐containing borazine compounds and their 13C NMR spectra

New borazine compounds containing steroid units (cholesteryl and stigmasteryl) were prepared by the reactions of B,B′,B″‐trichloro‐N,N′,N″‐trimethylborazine with the 3‐chloro derivatives of the corresponding steroids under Grignard conditions. The products were characterized by ¹³C–¹H correlation NMR measurements to give fully assigned ¹³C NMR data. Copyright © 2001 John Wiley & Sons, Ltd.     

A new method for separation and spectrophotometric determination of phosphate ion by the liquid-liquid extraction with benzophenone at an elevated temperature

Summary A new type of separation of phosphate ion, along with its spectrophotometric determination, was established by liquid-liquid extraction, where the yellow heteropoly acid formed by the reaction with ammonium molybdate in acid solution is quantitatively extracted into molten benzophenone at a temperature of about 60° C. When cooled down to room temperature, the benzophenone extract converts from the liquid state to the solid state. The resulting solidified extract is dissolved in methyl propionate, and the phosphate ion in the solvent is determined spectrophotometrically by the blue heteropoly acid method. Possible interference by Si, As and Ge is eliminated by the separation procedure.The authors wish to thank President Dr. Yawara Yoshitoshi and Prof. Yoshisaburo Ota of University School of Medicine, for their hospitality and encouragement.     

Boronate affinity saccharide electrophoresis: a novel carbohydrate analysis tool

The incorporation of specialised carbohydrate affinity ligand methacrylamido phenylboronic acid in polyacrylamide gels for fluorophore-assisted carbohydrate electrophoresis greatly improved the effective separation of saccharides that show similar mobilities in standard electrophoresis. Polyacrylamide gel electrophoresis using methacrylamido phenylboronic acid in low loading (typically 0.5-1% dry weight) was unequivocally shown to alter retention of labelled saccharides depending on their boronate affinity. While conventional fluorophore-assisted carbohydrate electrophoresis of 2-aminoacridone labelled glucose oligomers showed an inverted parabolic migration, an undesired trait of small oligosaccharides labelled with this neutral fluorophore, boron affinity saccharide electrophoresis separation of these carbohydrates completely restored their predicted running order, based on their charge/mass ratio, and resulted in improved separation of the analyte saccharides. These results exemplify boron affinity saccharide electrophoresis as an important new technique for analysing carbohydrates and sugar-containing molecules.     

Azacalix[4]arene cation radicals: spin-delocalised doublet- and triplet-ground states observed in the macrocyclic m-phenylene system connected with nitrogen atoms

Electron paramagnetic resonance spectroscopy has unmasked for the first time the spin-delocalised doublet- and triplet-ground states of azacalix[4]arene cation radicals.     

Formulation study of intravesical oxybutynin instillation solution with enhanced retention in bladder

A formulation study of intravesical oxybutynin (OB) preparations was carried out in order to improve the effectiveness in intravesical instillation therapy for spastic neurogenetic bladder. Sodium hyaluronate (HYA) was introduced to enhance the muco-adhesiveness of the instillation preparation, and the physicochemical properties of the OB formulation were evaluated in comparison with a conventional formulation containing hydroxypropylcellulose (HPC). The viscous properties and in vitro adhesiveness increased with the amount of the polymeric additives, and retention properties of OB in rabbit bladder were comparable after addition of 0.4% HYA and 1.0% HPC. HYA was able to enhance the intravesical retention properties of OB instillation solution to a lesser degree than HPC, it seemed to be a useful additive in the OB instillation due to its safety and mucosal-protective effect.     

Acyclic diterpene glycosides, capsianosides C, D, E, F and III, from the fruits of hot red pepper Capsicum annuum L. used in Kimchi and their revised structures

Acyclic diterpene glycosides, named capsianosides I', II, III (1), C (2), D (3), E (4) and F (5), have been isolated from the dried hot red pepper fruits of Capsicum annuum L. used in Kimchi. The structures of these compounds have been revised in the sugar connectivities by 1D- and 2D-NMR spectroscopic and chemical methods.     

Direct lactone formation by using hypervalent iodine(III) reagents with KBr via selective C-H abstraction protocol

We have developed a new and reliable method for the direct construction of biologically important aryl lactones and phthalides from carboxylic and benzoic acids, using a combination of hypervalent iodine(III) reagents with KBr.