Structure revision of ent-kaurane diterpenoids,isoserrins A,B, and D,enabled by DU8+ computation of their NMR spectral data

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Comparative Pharmacokinetics and Relative Bioavailability of a New Anxiolytic GML-1 in Tablet Form

Moscow University Chemistry Bulletin - An open, single, crossover, pharmacokinetic study of GML-1 (dose 50 mg/kg) in rabbits after its oral administration in tablets and alone as a substance is...     

Reflectometric studies of the etching of a silica fiber with a germanium silicate core in sub- and supercritical water

Fiber optic reflectometry (FOR) and scanning electron microscopy (SEM) were used to study the regularities of the etching of a single-mode optical silica fiber with a germanium silicate core in subcritical and supercritical water. It was demonstrated that the rate of etching of the germanium silicate core, being higher than that of etching of the silica cladding, was responsible for the formation of a well at the fiber end face, the depth of which increased with the time of etching. The temporal behavior of the FOR signal was of oscillatory character, an observation that accounted for the interference effects that accompany the reflection of radiation (from the photodiode used in the FOR) from the fiber end face during its etching (well deepening). The interference-controlled character of the FOR signal made it possible to directly measure the rate of etching of the fiber end face in water in its different phase states (gaseous, liquid, and supercritical) at various temperatures and pressures. The lowest measured rate of etching of the germanium silicate core (at 200°C and 54 atm) was 10⁻³ nm/s, whereas the highest measured rate was 30 nm/s (at 400°C and 246 atm). The temperature dependence of the etching rate was demonstrated to obey the Arrhenius law, with an activation energy of 58 ± 3 kJ/mol. At later stages of etching, the FOR signal changed from regular oscillatory to irregular noisy due to the formation defects of various sizes, as could be clearly seen in SEM images.     

Development and Validation of the Quantification of GML-1 Compound (<Emphasis Type="Italic">N</Emphasis>-benzyl-<Emphasis Type="Italic">N</Emphasis>-methyl-1-phenylpyrrolo[1,2-<Emphasis Type="Italic">A</Emphasis>] pyrazine- 3-carbamide) in the Blood Plasma of Rats by HPLC–MS

The technique of quantitative determination of a new compound, possessing anxiolytic activity, GML-1 in the blood plasma of rats is developed and validated. The analysis is performed by HPLC–MS. The method is linear in the range of 50–1000 ng/mL. 83.63% of GML-1 was recovered. The detection limit was 25 ng/mL.