[Streptonigron--a minor component of bruneomycin complex]. / Streptonigron--minornyi komponent bruneomitsinovogo kompleksa.

A mutant strain of the bruneomycin-producing culture which produced up to 10% of the minor component was selected. The component was identified as streptonigrone. It was isolated and its physicochemical properties and antibacterial activity were investigated. Trimethylsilyl derivatives of streptonigrone and bruneomycin were prepared. Their PMR spectra and electron impulse mass spectra were studied. Streptonigrone was shown to have antibacterial and cytotoxic activities which was 1 to 2 orders of magnitude lower than that of bruneomycin.

[Determination of carminomycin in its preparations by high-performance liquid chromatography]. / Opredelenie karminomitsina v ego preparatakh metodom vysokoéffektivnoi zhidkostnoi khromatografii.

A three component system for separating a mixture of carminomycin, carminomycinone and 13-dihydrocarminomycinone by HPLC was developed. Spherisorb ODS Column, 4.6 X 250 mm, the particle size of 10 micron was used. The impact of the mobile phase composition, temperature during chromatography and buffer solution pH on the capacity factors K' for every of the above compounds was studied. For determining purity of carminomycin dosage forms the procedure with an external standard was applied. The procedure provides routine quantitative assay of carminomycin hydrochloride dosage forms.

[Physicochemical properties of octamycin]. / Izuchenie nekotorykh fiziko-khimicheskikh svoistv oktamitsina.

Octamycin, an original polyenic antibiotic was developed. The antibiotic is of an amphoteric character. The number and nature of the functional groups were determined by potentiometric titration. It was shown that the antibiotic contained the neutral sugar galactose. The equivalent weight of the antibiotic (990) was measured by potentiometric titration and the content of the sugar in the molecule. With high performance liquid chromatography it was demonstrated that the antibiotic consisted of 2 components at a ratio of 1:2. The molecular weights of the components were evaluated with mass spectrometry.

[Quantitative determination of the antibiotic doxorubicin by high-performance liquid chromatography]. / Kolichestvennoe opredelenie antibiotika doksorubitsina metodom vysokoéffektivnoi zhidkostnoi khromatografii.

A new three-component system was developed for separation of a mixture containing 6 components: doxorubicin, rubomycin, dihydrorubomycin, 14-bromrubomycin, doxorubicinone and rubomycinone. The system uses reverse phase high performance liquid chromatography. Separation was performed on a column with Spherisorb C18 (4.6 X 250 mm) with the particle size of 10 microns. Relationships between the capacity factor k1 for the above 6 components and relative arresting alpha for 3 hardly separating components: doxorubicin, rubomycinone and dihydrorubomycin, as well as between the percentage content of the organic component, acetonitrile and the percentage content of the buffer solution were studied. The external standard method was used for determination of purity of doxorubicin standard preparations. The method provides routine quantitative assay of doxorubicin hydrochloride.

[Structure of the antibiotic virenomycin]. / Stroenie antibiotika virenomitsina.

To identify the structure of virenomycin, a new antitumor antibiotic consisting of components V and M, its acetyl and permethyl derivatives, as well as products of acid methanolysis and their derivatives were obtained. The IR-, NMR- and mass-spectra of the above compounds are presented. Based on an analysis of the spectral data the structure of virenomycin is suggested.

[Quantitative determination of the antibiotic tobramycin using high-performance liquid chromatography]. / Kolichestvennoe opredelenie antibiotika tobramitsina s pomoshch'iu vyskooéffektivnoi zhidkostnoi khromatografii.

Separation of the main components of the nebramycin complex of apramycin, kanamycin B and tobramycin was achieved in the form of their 2,4-dinitrophenyl derivatives. A chromatograph SR 8000 of 'Spectra-Physics" and a column 'Sperisorb C6" (4.6 X 250 mm) with the granule size of 5 micrometers were used in the study with the mobile phase of acetone-trisbuffer, pH 7 in a ratio of 65 to 35, the flow rate of 1 ml/min, a temperature of 35 degrees C and detection at lambda 350 nm. Quantitative determination of the tobramycin purity level was performed with an equation developed for the given conditions. The purity levels of the reference tobramycin base and its sulfate were estimated. The results of the estimation corresponded to the data of biological titration.

[Separation and characteristics of the components of the antibiotic virenomycin]. / Razdelenie i kharakteristika komponentov antibiotika virenomitsina.

The composition of virenomycin, a new antitumor antibiotic was studied. Two components V and M were detected with high resolution liquid chromatography and thin layer chromatography on siluphol (Czechoslovakia) and silica gel (Merk, BRD). A preparative method for separation of the antibiotic components with the use of chromatography on columns with silica gel was developed. Biological and physicochemical properties of separate components were studied to show that they significantly differed by their antibacterial action in vitro: virenomycin V was 2 to 4 times more active than virenomycin M against a number of microbes. The physicochemical properties of the components are similar. It was shown with mass spectrometry that the molecular weight of virenomycin is 12 units higher than that of virenomycin M. The PMR spectra showed that this difference is due to the presence of a vinyl group in the chromophore moiety of the virenomycin V molecule and a methyl group at the similar site of the virenomycin M molecule.

[Isolation and physicochemical study of the components of the new antibacterial antibiotic 2562]. / Poluchenie i fiziko-khimicheskoe izuchenie komponentov novogo antibakterial'nogo antibiotika 2562.

An antibacterial antibiotic complex consisting of 2 components designated as 2562 A and 2562 B is produced by Streptomyces griseovarabilis. The antibiotic was isolated from the mycelium and purified chromatographically on a column with aqueous silicic acid. The study of the components showed that component 2562 A was chlorbiocin, while component 2562 B differed from the known antibiotics of this group. Physicochemical assays demonstrated that component 2562 B differed from chlorbiocin by the absence of the methyl group in pyrrol, which is probably attached to sugar at beta-position. It was found that component 2562 B is a new representative of the antibiotic cumero-glycoside group.

[Minor components from the carminomycin complex]. / Minornye komponenty iz karminomitsinovogo kompleksa.

Three components differing by their properties from the carminomycins described earlier were isolated from the carminomycin complex. Comparison of the IR and UV spectra, as well as chromatographic and physicochemical properties of 2 of them showed that they were dihydrocarminomycin and its aglycone or dihydrocarminomycinone, which was prepared earlier by synthesis. The third component was a chromophore belonging to 1,4,6-trihydroxyanthraquinone. Investigation of its IR spectrum, physicochemica properties and PMR spectrum showed it to be carboxymethylethylcarminomycinone identical to epsilon-rodomycinone. The data were confirmed by 13C-NMR spectrometry.