Thyrocalcitonin. I. Isolation and characterisation of active peptices from pig thyroids

α- and β-thyrocalcitonic isolated from pig thyroids were found to be single-chain polypeptides with 32 amino acid residues containing a disulphide bridge. Tryptic digestion yielded inactive hepta-, undeca-and tetradecapeptides, the amino acid composition of which is given. β-thyrocalcitonin proved to be the methionine sulphoxide derivative of the easily oxidizable methionine peptide α-thyrocalcitonin; thus, the designation β can be eliminated. Both peptides have a potency of about 200 MRC units/mg dry weight. They can readily be differentiated by their electrophoretic and chromatographic properties, as well as by their tryptic undecapeptide, whereas the hepta- and tetradecapeptides, respectively, produced by trypsin are identical.     

Structure of the D phase. II

Results are presented of a Fourier analysis of quantitative X-ray diffraction data obtained from a D phase single crystal, the structure of which has previously been shown to possess primitive cubic symmetry. The Fourier analysis method determines the distribution of electron density in the crystallographic unit cell from the intensities and phases of the Bragg reflections. Diffraction data provide no information on the phase factors, and the Fourier method is therefore practical only when the structure is centrosymmetric, as is shown to be the case for the D phase, since the phase factors are then either 0 or π. It is shown that there are essentially only four physically reasonable solutions for the electron density distribution. The physical interpretation of these models is discussed in terms of molecular packing in the unit cell.     

Oxytropis alkaloids II. Structure of oxytriphine

The new alkaloid oxytriphine, the parent of natural 2-oxazoline derivatives, has been isolated from the epigeal part ofOxytropis trichophysa; and its structure has been established as (5S)-(+)-2,5-diphenyl-2-oxazoline. (-)-N-Benzoyl-2-phenyl-2-hydroxyethylamine and benzoic acid have been detected in this plant for the first time. A hypothesis of the possible biogenetic interrelationship of the compounds isolated is put forward.     

Diterpenoids ofPulicaria salviifolia. II. Structure of salvicin

A new diterpenoid acid of the clerodane series, C₂₀H₃₂O₄, [] _D ²⁰ –75.4° (c 0.26; methanol), which has been called salvicin, and the known flavonoid rutin have been isolated from a chloroform extract of the epigeal part ofPulicaria salviifolia. The structure of salvicin has been established on the basis of spectral characteristics and chemical transformations.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 299–301, May–June, 1986.     

Alkaloids of Aconitum sajanense II. Structure of dehydroacosanine

The new alkaloid dehydroacosanine has been isolated from the roots ofAconitum sajanense Kumin, and its structure has been established by spectral and chemical methods.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 531–534, September–October, 1992.     

Alkaloids of Aconitum sajanense II. Structure of dehydroacosanine

The new alkaloid dehydroacosanine has been isolated from the roots ofAconitum sajanense Kumin, and its structure has been established by spectral and chemical methods.     

Nitroimines: II. Structure of Nitroamino-1,2,4-triazoles

According to the X-ray diffraction data, compounds formerly known as 3(5)-nitroamino-1,2,4-triazoles are in fact N-nitroimines rather than primary N-nitroamines. Their chemical properties and UV and NMR spectra indicate their nitroimine structure in solution as well.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 928–933.Original Russian Text Copyright © 2005 by Astakhov, Vasil’ev, Molokeev, Revenko, Stepanov.     

Oxytropis alkaloids II. Structure of oxytriphine

The new alkaloid oxytriphine, the parent of natural 2-oxazoline derivatives, has been isolated from the epigeal part ofOxytropis trichophysa; and its structure has been established as (5S)-(+)-2,5-diphenyl-2-oxazoline. (-)-N-Benzoyl-2-phenyl-2-hydroxyethylamine and benzoic acid have been detected in this plant for the first time. A hypothesis of the possible biogenetic interrelationship of the compounds isolated is put forward.Institute of the Chemistry of Plant Substances. Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii. No. 6, pp. 873–876, November–December, 1993.     

Triterpene saponins fromThalictrum minus. II. Structure of an artefact

The acid hydrolysis of the predominating saponins isolated fromThalictrum minu? L. has led to the formation of a triterpenoid (I), which is an artefact of the native genin. The structure of (I) has been established as 22,25-epoxylanost-9(11)-ene-3β,16β,29-triol.