[Early identification of streptothricin group antibiotics].

Methodical approaches to detecting cultures producing streptothricins at the early stages of screening new antibiotics were developed. The approaches are based on chromatographic and electrophoretic mobility of streptothricins and the products of their hydrolysis in the extracts from agar cultures of actinomycetes. Application of the method for screening new antibiotics is illustrated with an example.

Eremomycin--new glycopeptide antibiotic: chemical properties and structure.

By a combination of chemical and spectroscopic (1H and 13C NMR) studies the structure of a glycopeptide antibiotic eremomycin has been elucidated. It is closely related to vancomycin, but differs in sugar and chlorine content. The eremomycin aglycone contains monodechlorovancomycinic acid; the only chlorine atom is situated in the second amino acid after the N-terminal amino acid residue of the peptide.

[Eremomycin--a new antibiotic of the polycyclic glycopeptide group].

Eremomycin is a novel antibacterial antibiotic. It was isolated at the Institute of New Antibiotics, the USSR Academy of Medical Sciences from the culture fluid of actinomycete INA-238. By its physico-chemical and biological properties the antibiotic was classified as belonging to the group of polycyclic glycopeptides.

[Determination of carminomycin in its preparations by high-performance liquid chromatography].

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 antineoplastic antibiotic polypeptide 308 produced by Actinomadura recticatena. Its isolation and physicochemical properties].

A antitumor antibiotic belonging to the group of polypeptide antibiotics containing chromophore was isolated from the culture of Actinomadura recticatena Terekhova, Preobrazhenskaya et Galatenko, 1984, strain 308. Biosynthesis, isolation, physicochemical and biological properties of the antibiotic are described. The results of elemental analysis, the melting point, optical properties, UV, IR and NMR spectra and the data on acid hydrolysis showed that antibiotic 308 was most closely related to antibiotic BBM-928 A.

[Eremomycin--a new antibiotic from the cyclic glycopeptide group].

Eremomycin, a novel antibiotic belonging to the group of cyclic glycopeptides is produced by an actinomycete designated INA-238. Biosynthesis, isolation, physico-chemical and biological properties of the antibiotic are described. Eremomycin is shown to be close to vancomycin.

[Physicochemical properties of octamycin].

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.

[The antibiotic varigomycin--a new representative of the carbonyl-conjugated pentaenes].

In screening new antibiotics, varigomycin produced by a new fungal species Streptomyces variegatus Sveshnikova et Timuk was isolated. By physicochemical properties varigomycin belongs to carbonyl conjugated pentaens. It is a new representative of this antibiotic group.

[Structure of the antibiotic virenomycin].

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.

[Formation of an antibiotic of the siomycin group by a Streptomyces corchorusii 1401 culture].

Streptomycete 1401 inhibiting the growth of gram-positive organisms was isolated from a soil sample in the screening of new antibiotics. By its cultural and morphological properties the culture was classified as Str. corchorusii.

[Quantitative determination of the antibiotic tobramycin using high-performance liquid chromatography].

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.

[Search for new antibiotics of the cyclosporin group].

A total of 160 fungal cultures belonging to Trichoderma were isolated from soil samples collected in various regions of the USSR. The cultures were tested for production of antibiotics of the cyclosporin group, having a narrow antifungal spectrum. It was found that 7 cultures produced substances having a selective inhibitory effect on Asp.

[Minor components from the carminomycin complex].

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.

[Structure of carminomycins II and III].

Carminomycins II and III, the main components of the carminomycin complex were isolated in pure state. Their crystalline exalates and acetate of cardminomycin II were prepared. The PMR spectra of both carminomycins and the 13C-NMR spectra of the oxalates were obtained.

[Isolation and physicochemical study of the components of the new antibacterial antibiotic 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.

The structure of nocamycin, a new antitumor antibiotic.

The structure of nocamycin, a new antitumor antibiotic, has been elucidated with the aid of mass- and PMR-spectroscopic investigation of the antibiotic and its various chemical transformation products. Nocamycin is structurally related to tirandamycins.

[Chromatographic method on a thin sorbent layer for studying the purity and quality of the antitumor antibiotic, rubomycin].

A method for qualitative and quantitative investigation of rubomycin composition was developed. It was based on chromatographic separation of the antibiotic components in a thin layer of silicic acid followed by their elution and spectrophotometric determination. An additional component of rubomycin found in the therapeutic preparations and the conditions of its formation were studied.

[Formation of the anthracycline antibiotics, beromycin and nogalamycin, by a new actinomycete species, Streptomyces glomeratus sp. nov].

Culture 3980 was isolated from a soil sample and described as a new species, Streptomyces glomeratus sp. nov. It was found that the culture produced simultaneously 2 close anthracycline antibiotics, i.

[Physico-chemical characteristics of the new antitumor antibiotic virenomycin].

Virenomycin, a new crystalline antitumor antibiotic was isolated from the mycelium of Streptomyces virens. The antibiotic contained: C 64.87 per cent, H 5.

[Physicochmemical characteristics of the new antineoplastic antibiotic, nocamycin].

Nocamycin is produced by Nocardiopsis syringae. It is recovered from the culture fluid by extraction with chloroform. The molecular weight of the crystalline antibiotic is 503, its melting point is 147--149 degrees, [alpha]20 degrees D = --50 degrees (c.