The reaction 16O(6Li,d)20Ne at 75 MeV

The angular distributions of the reaction ¹⁶O(⁶Li, d)²⁰Ne at 75 MeV for transitions to members of the ground state band are well fitted by exact finite-range DWBA calculations assuming a direct α-cluster transfer and yield spectroscopic factors in good agreement with shell-model predictions.     

Intersystem crossing in ir and rh complexes studied by nanosecond and picosecond spectroscopy

Absorption spectra of the lowest triplet state were measured for cis-[IrCl₂(phen)₂ ]Cl (A), cis-[RhCl₂(bpy)₂] Cl (B), and cis-[RhBi₂(bpy)₂] Br (C) in ethanol—methanol (vlv = 4: 1) at 19°C. An S_n « S₁ absorption spectrum was also measured for the Ir complex. The time constants for T₁ formation are 26 ± 10, ≈2.4, and ≈1.3 ps for A, B, and C, respectively.     

Development of a highly sensitive galvanic cell oxygen sensor

A highly sensitive galvanic cell oxygen sensor was successfully developed for determining parts per billion of oxygen in high purity gases such as nitrogen, argon, etc. The response of this improved sensor was proportional in the range of oxygen concentrations from 10.0 ppm to the detection limit. The response speed in this study was improved to within 90 sec for a 90% response. The detection limit was tentatively found to be less than 0.4 ppb corresponding to S N = 2 .     

A novel tert-butoxycarbonylation reagent: 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI)

The use of 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a tert-butoxycarbonylation reagent for acidic proton-containing substrates such as phenols, aromatic and aliphatic amines hydrochlorides, and aromatic carboxylic acids in the absence of a base is described. The reactions proceed chemoselectively in high yield under mild conditions.     

Gram-negative bacteria viable in ultrapure water: identification of bacteria isolated from ultrapure water and effect of temperature on their behavior

This study describes the effect of temperature on the behavior of bacteria viable in ultrapure water and the contamination of ultrapure water by bacteria. Three species of bacteria were isolated from ultrapure water (total organic carbon, 60 ppb and 5 ppb; effluent resistivity > 18 MΩ cm at 25°C) and identified by morphological and physiological characteristics. The three isolates were incubated in water for injection and PYG broth to check the growth profile at various temperatures. In PYG broth, temperature influenced the behavior of bacteria directly; however, it did not in water for injection. By checking both viable and non-viable bacterial numbers and endotoxin concentration in pure water, the water was found to be contaminated with non-viable bacteria and newly generated endotoxins besides viable bacteria. A column treatment, a mixed bed of fully regenerated strong acid cation exchange resin (SACER) and strong base anion exchange resin (SBAER), was used to remove bacteria from pure water. Bacteria could not grow on the surfaces of ion exchange resins in the mixed bed. The removal of bacteria was more effective as pure water was circulated through the mixed bed more rapidly.     

Prodrugs of 9-benzyl-8-hydroxy-2-(2-hydroxyethylthio)adenine: potent interferon inducing agents in monkeys

In order to improve the oral bioavailability of 9-benzyl-8-hydroxy-2-(2-hydroxyethylthio)adenine (SM-295072), a potent interferon (IFN) inducing agent, we synthesized prodrugs of it by utilizing the hydroxy groups at the C(2)-side chain and/or the C(8)-position. The carbonate prodrug at the C(8)-position was more effective than that at the C(2)-side chain for oral absorption in rats. Among the compounds prepared, compound 6 demonstrated the most preferable prodrug properties, and the maximum plasma concentration of 6 was approximately 4-fold higher than that of SM-295072. Furthermore, compound 6 was dose-dependently absorbed in monkeys by oral administration, and exhibited a potent IFN-inducting activity that correlated well with its plasma drug concentration.     

Simple and mild esterification of N-protected amino acids with nearly equimolar amounts of alcohols using 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline

A very mild, one-step esterification using nearly equimolar amounts of N-protected amino acids and alcohols, in conjunction with 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a novel condensing reagent is described.