Toxicity and pharmacological properties of carminomycin complex components]

Acute toxicity of the components of the carminomycin complex after intravenous administration to albino mice increased as follows. I less than II less than III. Component II induced a decrease in all the indices of the bone marrow and peripheral blood of the animals. It was most pronounced in dogs. The dogs died after administration of component II in the lethal doses as a result of the bone marrow aplasia. The indices of the functional state of the liver and kidneys in the animals after administration of components I and II changed slightly. Component III administered repeatedly to rabbits even in low doses induced significant impairments in the function of the liver and kidneys. Component II differed from component I by more pronounced cardiotoxicity. On the basis of the experimental data and the results published earlier component I is recommended for clinical trials as the least toxic one.     

Structure of the antineoplastic antibiotic variamycin]

The results of the structural study of antitumor antibiotic variamycin and its peracetyl derivative by 1H-and 13C-NMR spectroscopy are reported. Structures of carbohydrate chains of the antibiotics molecule are revised. Variamycin is shown to be 2-[beta-cymmarosyl(1-3)-beta-oliosyl (1-3)-beta-olivosyl]-6-[beta-olivosyl (1-3)-beta-olivosyl] chromomycinone.     

Synthetic metalloporphyrins: a class of compounds of pharmacological interest

Studies of the regulation of heme oxygenase by synthetic metalloporphyrins reveal that within this group of compounds there exist both inducers and inhibitors of the synthesis of this enzyme or of its catalytic function. The ability of metalloporphyrins to alter heme catabolism is of considerable experimental and clinical interest since such alterations may have consequences for other aspects of heme homeostasis, including its synthesis and its function in the form of cytochrome(s) P-450. Examples of the metabolic effects – and their potential clinical and pharmacological consequences – produced by two synthetic metalloporphyrins, Sn-protoporphyrin and Co-protoporphyrin, are discussed.     

Cytogenetic effect of the antineoplastic anthracycline antibiotic 4'-epidoxorubicin

Cytogenetic action of 4'-epidoxorubicin (farmorubicin), an antitumor antibiotic was studied with using rat bone marrow cells. It was shown that after intraperitoneal administration the antibiotic increased the number of the aberrant metaphases when the dose was not lower than that equivalent to 1/30 of the LD50. The number of the aberrant metaphases increased with increasing of the antibiotic dose. The maximum number of the cells with impaired chromosomal apparatus was observed 6 hours after the antibiotic administration. In 72 hours it decreased to the level of spontaneous mutations in myelocariocytes. Cytogenetic activity of 4'-epidoxorubicin was comparable to that of doxorubicin (adriablastin) widely used in medical practice.