[Synthetic transformations of higher terpenoids. XXX. Synthesis and cytotoxic activity of betulonic acid amides with a piperidine or pyrrolidine nitroxide moiety].

The reaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpeperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl gave corresponding triterpenoid amides. It was found that new derivatives exhibit cytotoxic activity against tumor cells CEM-13, U-937, MT-4. CCID50 value for most activity compound--N-[3-oxolup-20(29)-en-30-yl]-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl--was 5.7-33.1 microM.

[Hepatoprotective activity of betulonic acid amides containing a piperidine or pyrrolidine nitroxide moiety].

Betulonic acid amides containing a nitroxyl radical moiety possess antiholestatic effects in mice. Introduction ofpiperidine nitroxide moiety into lupan core increases its hepatoprotective activity. Oral administration of piperidine nitroxide derivative in dose 50 mg/kg doesn't stimulate transplanted tumor growth and raises a lifespan of mice.

[Effect of nitrogen-containing derivatives of the plant triterpenes betulin and glycyrrhetic acid on the growth of MT-4, MOLT-4, CEM, and Hep G2 tumor cells].

Derivatives of the available plant triterpenes glycyrrhetic acid and betulin (betulin succinates and amides of betulonic and 18beta-glycyrrhetic acids containing fragments of long-chain amino acids and a peptide) were synthesized. The inhibitory action of these compounds on the growth of MT-4, MOLT-4, CEM. and Hep G2 tumor cells and their effect on the apoptosis of these cells were studied. It was shown that betulonic acid amides are more effective inhibitors of the tumor cell growth than the corresponding amides of glycyrrhetic acid. It was also found that betulonic acid amides containing fragments of caprylic, pelargonic, and undecanoic acids are more effective inhibitors of tumor cell growth than betulinic acid. The 17-dipeptide derivative of betulonic acid N-{N-[3-oxo-20(29)-lupen-28-oyl]-9-aminononanoyl}-3-amino-3-phenylpropionic acid exhibited the maximum inhibitory activity toward the tumor cells studied. Data on the induction of apoptosis in tumor cells by betulin derivatives at a concentration of 10 microg/ml were obtained by flow cytometry. The amides of betulonic acid proved to be the most effective inducers of apoptosis.

Antitumor and antimetastatic effects of betulonic acid amides in mice with transplantable lewis carcinoma.

We studied the effects of four synthetic amides of betulonic acid containing amino acid fragments (d,l-alpha-alanine, beta-alanine, and their methyl esters) on the rate of growth and metastatic dissemination of transplantable Lewis lung carcinoma in C57Bl/6 mice. The test compounds were administered intragastrically in a single dose of 500 mg/kg. 3-[-oxo-20(29)-lupen-28-oilamino]-propionic acid suppressed primary tumor growth (by 26%) and decreased the number of lung metastases (by more than 2 times). Antitumor and antimetastatic activity of triterpenoids decreased after methylation of the amino acid fragment in betulonic acid.

[Antiviral activity of vegetable triterpens, their derivatives and ribavirin phosphonates]. / Protivovirusnaia aktivnost' triterpenov rastitel'nogo proiskhozhdeniia, ikh proizvodnykh i fosfonatov ribavirina.

The purpose of the study was to investigate, in the Vero cell culture, the antiviral activity of vegetable tritrpens derivatives and ribavirin analogues against the viruses of measles, herpes simple (type 1), cytomegaloviruses and filoviruses. The toxicity and antiviral activity of compounds were determined after coloring of cells with crystal violate. Additionally, the combined action of triterpens' derivatives and ribavirin was investigated. The studied compounds showed relatively low antiviral activity, nonetheless, further research of vegetable triterpens and their derivatives as well as ribavirin analogues would be promising.

[Intermolecular interactions of dipeptide triterpene derivatives and natural quinones with alpha-tocopherol]. / Mezhmolekuliarnye vzaimodeistviia dipeptidnykh proizvodnykh triterpenoidov i prirodnykh khinonov s tokoferolom.

In modeling system of the initiated oxidation of methyl oleate the antioxidation activity of a series of dipeptide derivatives of betulonic and glycyrrhetic acids, natural quinones (ubiquinone, philloquinone and menadione) and the kinetic effects of their combined action with alpha-tocopherol were studied. The same extreme character of the dependence of inhibitory action on the concentration of all investigated substances was found. Combined addition of triterpenoids or quinones together with alpha-tocopherol attenuated their effect. The mechanism of intermolecular interactions of tocopherol with quinones and triterpenoids is offered. The biological importance of these effects is discussed.